<div><h4>How to perform effective cryoballooon ablation of the left atrial roof: Considerations after experiencing more than 1000 cases.</h4><i>Shigeta T, Okishige K, Murata K, Oda A, ... Sasano T, Yamauchi Y</i><br /><b>Introduction</b><br />Cryoballoon ablation (CBA) of the left atrial (LA) roof in addition to a pulmonary vein isolation has been expected to improve the clinical outcomes post-atrial fibrillation (AF) ablation. We demonstrated the characteristics and efficacy of CBA of the LA roof through our experience with a large volume of procedures.<br /><b>Methods</b><br />Among 1036 AF ablation procedures with CBA of the LA roof, 834 patients who underwent a de novo ablation were analyzed.<br /><b>Results</b><br />Complete LA roof line conduction block was obtained in 767 patients (92.0%) solely by CBA (Group A). Compared with the other patients (Group B), the mean nadir balloon temperature during CBA of the LA roof (-44.5 ± 5.6°C for Group A vs. -40.5 ± 7.5°C for Group B, p < .01) and number of cryoballoon applications during the LA roof ablation with a circular mapping catheter located in the left superior pulmonary vein (1.3 ± 0.8 for Group A vs. 1.6 ± 1.0 for Group B, p = .02) were significantly lower in Group A. A multivariate analysis revealed that those were predictors of a complete LA roof conduction block after only CBA. The 1-year Kaplan-Meier atrial arrhythmia free rate estimates were 80.6% for Group A and 59.0% for Group B (p < .01).<br /><b>Conclusion</b><br />Complete LA roof line conduction block could be obtained with a cryoballoon without touch-up ablation in most cases. The LA roof CBA with a circular mapping catheter located in the right superior pulmonary vein was preferable to obtaining complete LA roof conduction block, which was important with regard to the clinical outcomes.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 26 Sep 2023; epub ahead of print</small></div>

<div><h4>Catheter ablation approach and outcome in HIV+ patients with recurrent atrial fibrillation.</h4><i>La Fazia VM, Pierucci N, Mohanty S, Gianni C, ... Di Biase L, Natale A</i><br /><b>Introduction</b><br />Earlier studies have shown a clear association between severity of human immunodeficiency virus (HIV) infection and incident atrial fibrillation (AF). We present the long-term outcome of catheter ablation (CA) and electrophysiological characteristics in HIV+ AF patients.<br /><b>Methods</b><br />This study evaluated 1438 consecutive AF patients [31 (2.15%) with HIV and 1407 (97.8%) without HIV diagnosis] undergoing their first CA at our center. A total of 31 HIV patients and 31 controls were generated by propensity matching, based on calculated risk factor scores, using a logistic model. During first procedure, all received isolation of pulmonary vein (PV) + posterior wall and superior vena cava. Non-PV triggers, defined as ectopic triggers originating from sites other than PVs, were identified at the redo ablation with high-dose isoproterenol challenge.<br /><b>Results</b><br />Clinical characteristics were not different between the groups. When compared to the control, by the end of 5 years after the first procedure, recurrence was significantly greater in HIV group [100% vs. 54%, p < .001]. Among patients that underwent redo ablation non-PV triggers were higher in HIV group [93.5% vs. 54%, p < .001], and most frequently originated from the coronary sinus [67.7% vs. 45.2%, p < .001] and left atrial appendage [41.9% vs. 25.8%, p < .001]. After focal ablation of non-PV trigger, no difference in arrhythmia recurrence between two groups [80.6% vs. 87.1%, p = .753] at 1-year follow up was found.<br /><b>Conclusion</b><br />Our findings suggest that non-PV triggers are highly prevalent in HIV+ AF patients resulting in higher rate of the mid- and long-term arrhythmia recurrence.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 25 Sep 2023; epub ahead of print</small></div>

<div><h4>Current and novel percutaneous epicardial access techniques for electrophysiological interventions: A comparison of procedural success and safety.</h4><i>Tonko JB, Lambiase PD</i><br /><AbstractText>Accessing the pericardial space safely and efficiently is an important skill for interventional cardiac electrophysiologist. With the increased recognition of the complexity of the 3-dimensional arrhythmogenic substrate due to advances in imaging and mapping technologies there has been an expansion of epicardial procedures in recent years. Equally, minimally invasive implantation of epicardial pacing, cardiac resynchronization, or defibrillation leads is expanding in specific patients where transvenous systems are contraindicated or their long term sequelae should be ideally avoided. Selective delivery of intrapericardial pharmacological antiarrhythmic therapy is yet another potential indication, albeit still investigational. The expanding indications for percutaneous epicardial procedures is contrasted by the still substantial risk and challenges associated with accessing the pericardial space. Myocardial perforation, coronary artery laceration, and damage to the surrounding organs are all recognized and feared complications. A number of innovative epicardial access techniques have been proposed to overcome the difficulties and risks of traditional dry subxiphoid punctures and may allow for more widespread use of epicardial access in the future. We review 10 different established and novel subxiphoidal epicardial access techniques describing procedural success rates, safety profile and overall experience. The technical aspects as well as access times and costs for extra equipment will be reviewed. Finally, an outlook of reported preclinical techniques awaiting in-human feasibility studies is provided.</AbstractText><br /><br />©2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 21 Sep 2023; epub ahead of print</small></div>

<div><h4>Outcomes of leadless pacemaker implantation after cardiac surgery and transcatheter structural valve interventions.</h4><i>Huang J, Bhatia NK, Lloyd MS, Westerman S, ... El-Chami MF, Merchant FM</i><br /><b>Introduction</b><br />Permanent pacing indications are common after cardiac surgery and transcatheter structural valve interventions. Leadless pacemakers (LPs) have emerged as a useful alternative to transvenous pacemakers. However, current commercially available LPs are unable to provide atrial pacing or cardiac resynchronization and relatively little is known about LP outcomes after cardiac surgery and transcatheter valve interventions.<br /><b>Methods</b><br />This retrospective study included patients who received a Micra VR (Micra<sup>TM</sup> MC1VR01) or Micra AV (Micra<sup>TM</sup> MC1AVR1) (Medtronic) leadless pacemaker following cardiac surgery or transcatheter structural valve intervention between September 2014 and September 2022. Device performance and clinical outcomes, including ventricular pacing burden, ejection fraction, and need for conversion to transvenous pacing systems, were evaluated during follow-up.<br /><b>Results</b><br />A total of 78 patients were included, of whom 40 received a Micra VR LP implant, and 38 received a Micra AV LP implant. The mean age of the cohort was 65.9 ± 17.9 years, and 48.1% were females. The follow-up duration for the entire cohort was 1.3 ± 1.1 years: 1.6 ± 1.3 years for the Micra VR group and 0.8 ± 0.5 years for the Micra AV group. Among the cohort, 50 patients had undergone cardiac surgery and 28 underwent transcatheter structural valve interventions. Device electrical performance was excellent during follow-up, with a small but clinically insignificant increase in ventricular pacing threshold and a slight decrease in pacing impedance. The mean right ventricle pacing (RVP) burden significantly decreased over time in the entire cohort (74.3% ± 37.2% postprocedure vs. 47.7% ± 40.6% at last follow-up, p < .001), and left ventricle ejection fraction (LVEF) showed a modest but significant downward trend during follow-up (55.0% ± 10.6% vs. 51.5% ± 11.2% p < .001). Patients with Micra VR implants had significantly reduced LVEF during follow-up (54.1% ± 11.9% vs. 48.8% ± 11.9%, p = .003), whereas LVEF appeared stable in the Micra AV group during follow-up (56.1% ± 9.0% vs. 54.6% ± 9.7%, p = .06). Six patients (7.7%) required conversion to transvenous pacing systems, four who required cardiac resynchronization for drop in LVEF with high RVP burden and two who required dual-chamber pacemakers for symptomatic sinus node dysfunction.<br /><b>Conclusion</b><br />Leadless pacemakers provide a useful alternative to transvenous pacemakers in appropriately selected patients after cardiac surgery and transcatheter structural valve interventions. Device performance is excellent over medium-term follow-up. However, a significant minority of patients require conversion to transvenous pacing systems for cardiac resynchronization or atrial pacing support, demonstrating the need for close electrophysiologic follow-up in this cohort.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 20 Sep 2023; epub ahead of print</small></div>

<div><h4>Antidromic and orthodromic reciprocating tachycardias over a novel left-sided accessory pathway involving the vein of Marshall and coronary sinus musculature.</h4><i>Kanzaki Y, Morishima I, Miyazawa H, Shimojo K</i><br /><b>Introduction</b><br />Herein, we present a rare case of the successful ablation of an accessory pathway (AP) involving the Marshall Bundle (MB) and coronary sinus musculature (CSM) in a 40-year-old man with Wolff-Parkinson-White syndrome.<br /><b>Methods and results</b><br />An orthodromic reciprocating tachycardia (ORT) was inducible with the earliest atrial activation site located at the posterolateral mitral annulus. The local conduction and the cycle length of ORT was prolonged by peri-mitral ablation; however, it failed to block the AP. The atrial insertion of the AP was identified by remapping during ORT at the left atrial ridge, which was away from the mitral annulus, where ablation was successful. Together with the electrophysiological findings in CSM potentials, we conclude that the epicardial MB-CSM connection functioned as the AP in this patient.<br /><b>Conclusion</b><br />The novel variant form of AP comprised of MB and CSM should be noted. The atrial insertion of the MB may be the target of catheter ablation.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 20 Sep 2023; epub ahead of print</small></div>

<div><h4>Predictors and possible mechanisms of premature ventricular contraction induced cardiomyopathy.</h4><i>Pundi K, Marcus GM</i><br /><AbstractText>Premature ventricular complexes (PVCs) are encountered frequently in clinical practice. While PVCs may have various causes, a small number of individuals with PVCs develop cardiomyopathy in the absence of other potential etiologies. When correctly identified, patients with PVC-incuded cardiomyopathy can have dramatic improvement of their cardiomyopathy with treatment of their PVCs. In this focused review, we discuss potential predictors of PVC-induced cardiomyopathy, including PVC frequency, PVC characteristics, and modifiable patient risk factors. We also review some proposed mechanisms of PVC-induced cardiomyopathy and conclude with future directions for research and clinical practice.</AbstractText><br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 19 Sep 2023; epub ahead of print</small></div>

<div><h4>Feasibility and safety of left bundle branch area pacing in patients with septal hypertrophy.</h4><i>Özpak E, Van Heuverswyn F, Timmermans F, De Pooter J</i><br /><b>Introduction</b><br />Left bundle branch area pacing (LBBAP) aims to provide physiological ventricular activation during pacing. Left ventricular septal hypertrophy (LVSH) might be challenging for LBBAP due to the thickness of the interventricular septum and potential presence of septal scar. This study assesses the feasibility, safety, and outcome of LBBAP in patients with LVSH using primarily stylet-driven leads (SDL).<br /><b>Methods</b><br />Adult patients with LVSH who underwent LBBAP between March 2019 and November 2022 were enrolled. Baseline patient characteristics, procedural data and postprocedural results were collected. The feasibility of LBBAP in LVSH patients was compared to a cohort of LBBAP patients with normal septal wall thickness (NST).<br /><b>Results</b><br />Seventeen LVSH and 133 NST patients underwent LBBAP with successful implantation achieved in 15 LVSH patients (88%). Mean implant depth was 17.2 ± 1.9 mm, with 53% proven left bundle branch (LBB) capture. Paced QRS duration (146 ± 14 ms) and V6 R-wave peak time (V6 RWPT; 79 ± 20 ms) were comparable between patients with and without septal hypertrophy, although patients with NST had higher rates of proven LBB capture (71% vs. 53%). In LVSH pacing thresholds (0.6 ± 0.3 V at 0.4 ms) and R-wave amplitude (13.9 ± 5.6 mV) were favorable and remained stable at follow-up. At 12 months, 87% of patients had stable or improved left ventricular ejection fraction.<br /><b>Conclusion</b><br />The results of the study indicate that LBBAP in patients with LVSH is safe and feasible and no lead-related complications were observed despite a mean implant depth exceeding 15 mm. LBBAP using SDL results in favorable pacing and electrocardiographic characteristics in LVSH patients, comparable to patients with NST.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 17 Sep 2023; epub ahead of print</small></div>

<div><h4>Isolated JUP plakoglobin gene mutation with left ventricular fibrosis in familial arrhythmogenic right ventricular cardiomyopathy.</h4><i>Zinkovsky D, Sood MR</i><br /><b>Introduction</b><br />Arrhythmogenic right ventricular cardiomyopathy (ARVC) is a rare inherited disorder usually affecting the right ventricle (RV), characterized by fibro-fatty tissue replacement of the healthy ventricular myocardium. It often predisposes young patients to ventricular tachycardia, heart failure, and/or sudden cardiac death. However, recent studies have suggested predominantly left ventricle (LV) involvement with variable and/or atypical manifestations. Cardiac magnetic resonance (CMR) imaging has emerged as the noninvasive gold standard for the diagnosis of ARVC.<br /><b>Case summary</b><br />A 21-year-old athletic male with a family history of unknown ventricular arrhythmias, presented with near syncope, chest pain, and exertional palpitations. He had an initial work-up that was grossly unremarkable including an electrocardiogram (ECG), echocardiogram and a CMR study. Six months later, he presented again with recurrent symptoms of presyncope during exercise and his ECG demonstrated new findings of a terminal activation delay in his precordial leads. He had markedly elevated cardiac biomarkers, (troponin I > 100 ng/dl, normal value < 0.04 ng/dl) and demonstrated ventricular tachycardia with a right bundle branch morphology. An endomyocardial biopsy did not reveal any pathology. A follow-up CMR demonstrated the new development and prominent left ventricular epicardial scar in the lateral wall. The patient underwent familial genetic testing, which confirmed the presence of an isolated junction plakoglobin (JUP) gene mutation and showed multiple genes consistent with ARVC in his mother. Thus, he manifested a partial transmission of only one abnormal gene for ARVC and exhibited a markedly different expression in his disease without evidence of typical right-sided heart pathology. A third CMR study was performed, which showed partial improvement in myocardial fibrosis after exercise cessation.<br /><b>Conclusion</b><br />We present a case of a young athletic male with a newly diagnosed isolated JUP gene mutation and a genetically diagnosed family history of ARVC. During his course, he demonstrated the progression of new, atypical, left ventricular fibrosis. This case demonstrates a complex interplay between genetic penetrance, phenotypical heterogeneity, and lifestyle factors such as exercise in disease progression and provides insight into the natural course of an isolated JUP mutation. Although rare, clinicians should have a high threshold for the clinical suspicion of ARVC or variants of this disorder even in the absence of classic right-sided pathologies.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 17 Sep 2023; epub ahead of print</small></div>

<div><h4>Unidirectional conduction characterizing epicardial connections in patients with atrial tachyarrhythmias.</h4><i>Yoshida K, Hasebe H, Hattori M, Hanaki Y, ... Nogami A, Takeyasu N</i><br /><b>Introduction</b><br />Electrophysiological characteristics of epicardial connections (ECs) in atria and pulmonary veins (PVs) are unclear despite their important contributions to atrial fibrillation (AF). Unidirectional conduction associated with source-sink mismatch can occur in ECs due to their fine fibers with abrupt changes in orientation. We detailed the prevalence and electrophysiological characteristics of unidirectional conduction in the atria and investigated its association with the clinical manifestation of AF.<br /><b>Methods</b><br />This study retrospectively reviewed electrophysiological studies and radiofrequency catheter ablation in 261 consecutive patients with AF.<br /><b>Results</b><br />Unidirectional conduction was observed during ablation encircling the PVs in eight (3.1%) patients, and all occurred in the suspected (N = 4) or definitively (N = 4) recognized ECs. These ECs included three intercaval bundles, four septopulmonary bundles, and one Marshall bundle, and were first manifested in a second procedure in 6 (75%) patients. The unidirectional property was from PV to atrium (exit conduction) in all intercaval bundles and three septopulmonary bundles, and from atrium to PV (entrance conduction) in the remaining two bundles. Intercaval bundles acted as a limb of bi-atrial macro-reentrant tachycardia (50%, three of the six including previous cases). Ablation of the exit outside the PVs, including the right atrium, eliminated ECs in three (38%) patients. All patients remain free from arrhythmia recurrence after a mean 13-month follow-up.<br /><b>Conclusion</b><br />A unidirectional conduction property was closely associated with the EC, as estimated by histological findings. Recognition of this fact by electrophysiologists may help to clarify mechanisms for AF and atrial tachycardia and guide the creation of efficient and safe ablation lesion sets.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 15 Sep 2023; epub ahead of print</small></div>

<div><h4>Possible systolic fascicular potentials in patients with left bundle branch block undergoing left bundle branch area pacing: A case series.</h4><i>Coluccia G, Accogli M, Parlavecchio A, Palmisano P</i><br /><b>Introduction</b><br />In left bundle branch area pacing (LBBAP), several methods allow determination of lead depth during active fixation inside the septum: among these, visualization of a Purkinje potential indicates that the subendocardial area has been reached. In LBB block (LBBB) patients, fascicular potentials are visible as presystolic only in rare conditions.<br /><b>Methods and results</b><br />Since October 2022 until August 2023, LBBAP was attempted in 21 patients with LBBB at our Center: among the 18 consecutive patients (86%) in which it was successful, focusing on the terminal part of the unipolar ventricular electrogram (VEGM) recorded in the LBBA (where fixation beats occurred and conduction system (CS) capture was confirmed), we always observed discrete high-frequency, low-amplitude signals during spontaneous rhythm with LBBB morphology, showing a consistent coupling with the QRS onset, falling in a portion of QRS interval ranging from 58% to 80% of its overall duration, and disappearing during pacing. As found in a recently published case report, these sharp signals could represent the activation of left ventricular CS fibers, occurring passively from the septal working myocardium, and thus appearing lately in the VEGM.<br /><b>Conclusion</b><br />The possibility of recognizing discrete high-frequency, low-amplitude signals within the terminal portion of the unipolar VEGM, possibly representing left CS potentials, even in patients with LBBB, may constitute a useful additional means to notice operators about having reached the LBBA, thus helping to avoid perforation in the left ventricle.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 15 Sep 2023; epub ahead of print</small></div>

<div><h4>Novel approaches for leadless pacemaker implantation in the extra-cardiac Fontan cohort: Options to avoid leaded systems or epicardial pacing.</h4><i>Goulden CJ, Khanra D, Llewellyn J, Rao A, Evans A, Ashrafi R</i><br /><b>Background</b><br />Fontan surgery, a palliative procedure for single ventricle patients, often leads to the need for permanent pacing. Epicardial pacing has limitations, while transvenous pacing carries risks in the Fontan circulation. This case series introduces a novel approach of leadless pacemaker implantation in the extra-cardiac Fontan (ECF) cohort to overcome these limitations.<br /><b>Methods</b><br />The study includes four cases of leadless pacemaker (Micra™) implantation in patients with ECF. Procedures were performed under general anesthesia with guidance from trans-esophageal echocardiography. Various access routes were used, including trans-carotid and trans-fenestration approaches. Procedural details, parameters, and follow-up data were collected.<br /><b>Results</b><br />All leadless pacemaker implantations were successful, with satisfactory electrical parameters and stable pacing postprocedural outcomes during short-term follow-up. One patient required closure of their fenestration for symptomatic desaturation post procedurally.<br /><b>Conclusions</b><br />Leadless pacemaker implantation via trans-carotid and trans-fenestration approaches appears to be a feasible back up option for pacing in Fontan patients where other options have been exhausted or there is a patient choice to avoid surgery. These techniques provide an option to avoid leaded systems or epicardial pacing, reducing the need for multiple thoracotomies and addressing challenges associated with surgical pacing leads. Further studies are needed to evaluate long-term outcomes and assess the broader application of leadless pacemakers in the Fontan population.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 15 Sep 2023; epub ahead of print</small></div>

<div><h4>Pulsed field ablation for pulmonary vein isolation: Preclinical safety and effectiveness of a novel hexaspline ablation catheter.</h4><i>Yu F, Dong X, Ding L, Reddy V, Tang M</i><br /><b>Background</b><br />Pulsed-field ablation (PFA) has emerged as a nonthermal energy source for cardiac ablation, with potential safety advantages over radiofrequency ablation (RFA) and cryoballoon ablation.<br /><b>Objective</b><br />To report the preclinical results of a novel hexaspline PFA catheter for pulmonary vein isolation (PVI), and to verify the influence of PFA on esophagus by comparing with RFA.<br /><b>Methods</b><br />This study included a total of 15 canines for the efficacy and safety study and four swine for the esophageal safety study. The 15 canines were divided into an acute cohort (n = 3), a 30-day follow-up cohort (n = 5) and a 90-day follow-up cohort (n = 7), PVI was performed with the novel hexaspline PFA ablation catheter. In the esophageal safety study, four swine were divided into PFA cohort (n = 2) and RFA cohort (n = 2), esophageal injury swine model was adopted, the esophagus was intubated with an esophageal balloon retractor, under fluoroscopy, the DV8 device was inflated with a mixture of saline and contrast and rotated to displace the esophagus rightward and anteriorly toward the ablation catheter in the inferior vena cava (IVC) and right inferior pulmonary vein (PV). Nine PFA applications were delivered at four locations on IVC and two locations on the right inferior PV in the PFA cohort, six RFA applications were delivered at each location in the RFA group. Histopathological analysis of all PVs, esophagus, IVC, and the adjacent lungs was performed.<br /><b>Results</b><br />Acute PV isolation was achieved in all 15 canines (100%), with energy delivery times of less than 3 min/animal. In the 30 and 90 days group, the overall success rates were 88.9% and 88.5% per PVs, respectively. Two right superior pulmonary veins (RSPVs) in the 30-day group, two RSPVs and one left superior PV in the 90-day group with recovered potentials. At follow-up, gross pathological examination revealed the lesions around the PVs were continuous and transmural. Masson\'s trichrome staining revealed the myocardial cells in the PVs became fibrotic, but small arteries and nervous tissue were preserved. Results of swine esophageal injury model revealed the esophageal luminal surface was smooth and without evidence for esophageal injury in the PFA group, whereas obvious ulceration was detected on the esophagus tunica mucosa in the RFA group.<br /><b>Conclusion</b><br />In the chronic canine study, PFA-based PVI were safe and effective with demonstrable sparing of nerves and venous tissue. Compared with RFA, there was also good evidence for safety of PFA, avoiding PV stenosis and esophageal injury. This preclinical study provided the scientific basis for the first-in-human endocardial PFA studies.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 15 Sep 2023; epub ahead of print</small></div>

<div><h4>Venous anatomy of the left ventricular summit region: Insights from high-speed rotational retrograde angiography.</h4><i>Mi L, Zhang K, Zhang H, Ding L, ... Dong X, Tang M</i><br /><b>Introduction</b><br />Mapping and ablation through the coronary venous system (CVS) have shown potential for ventricular arrhythmias originating from the left ventricular summit (LVS). Multielectrode catheters and balloons are frequently used for mapping and venous ethanol ablation (VEA). However, there is limited data on the venous size and drainage condition in the LVS region. This study aimed to investigate the morphology, angiographic size, and drainage condition of LV summit veins via high-speed rotational angiography (RA).<br /><b>Methods</b><br />We measured and analyzed the size of the great cardiac vein (GCV), the anterior interventricular vein (AIV), veins near to the LVS, and other main tributaries of CVS in 102 patients undergoing electrophysiology study.<br /><b>Results</b><br />Rotational retrograde angiography of LVS was successfully performed in 81 patients. The diameter of GCV at the level of the Vieussens valve and the distal end of GCV (junction of GCV-AIV) was larger in males than females (6.8 ± 1.1 vs. 5.6 ± 1.2 mm, p < .001; 5.2 ± 0.9 vs. 4.6 ± 0.8, p = .002, respectively) while no significant gender differences were observed in other tributaries. The LV summit veins presented downward drainage direction in half of the patients, indicating potential anatomic adjacency with His bundle. Left anterior oblique (LAO) 45° projection might provide the practical and optimal view of the LV summit veins.<br /><b>Conclusions</b><br />The coronary veins of the LVS region present various anatomical morphologies and ostium sizes. We provide a systematic description and angiographic size spectrum of CVS. RA could facilitate assessing the feature of CVS comprehensively.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 13 Sep 2023; epub ahead of print</small></div>

<div><h4>A novel ablation strategy for recurrent atrial fibrillation: Fractionated signal area in the atrial muscle ablation 1-year follow-up.</h4><i>Hirokami J, Nagashima M, Fukunaga M, Korai K, ... Ando K, Hiroshima K</i><br /><b>Introduction</b><br />Treatment of recurrent atrial fibrillation (AF) is sometimes challenging due to non-pulmonary vein (PV) foci. Fractionated signal area in the atrial muscle (FAAM) is a valid predictor of the location of non-PV foci. FAAM ablation has the potential to decrease the recurrence rate of atrial tachyarrhythmia in patients with recurrent AF. We compared the clinical impact of FAAM ablation for recurrent AF, using 1 year follow up date.<br /><b>Methods</b><br />A total of 230 consecutive patients with symptomatic recurrent AF who underwent catheter ablation specifically targeting non-PV foci as FAAM-guided ablation (n = 113) and non-FAAM-guided ablation (n = 117) were retrospectively analyzed. FAAM was assigned a parameter (peaks slider, which indicates the number of components of fractionated signals), ranging from 1 to 15, indicating the location of the FAAM (1: largest, 15: smallest). FAAM-guided ablation was performed by ablating FAAM until none inducibility of non-PV foci. On the other hand, non-FAAM-guided ablation was performed via linear ablation, complex fractionated atrial electrogram ablation, superior vena cava isolation, and focal ablation according to the location of the non-PV foci. The RHYTHMIA system was used to perform all the procedures. The primary endpoints were AF recurrence, atrial flutter, and/or atrial tachycardia.<br /><b>Results</b><br />After a 1-year follow up, freedom from atrial tachyarrhythmia was achieved in 90.3% and 75.2% of patients in the FAAM and non-FAAM groups, respectively (hazard ratio = 0.438 [95% confidence interval: 0.243-0.788], p  =  .005).<br /><b>Conclusions</b><br />FAAM ablation showed a promising decrease in the recurrence rate of atrial tachyarrhythmia in patients with recurrent AF during a 1-year follow-up.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 13 Sep 2023; epub ahead of print</small></div>

<div><h4>Prospective validation of a risk score to predict pacemaker implantation after transcatheter aortic valve replacement.</h4><i>Black GB, Kim JH, Vitter S, Ibrahim R, ... Babaliaros VC, Kiani S</i><br /><b>Introduction</b><br />The need for pacemaker is a common complication after transcatheter aortic valve replacement (TAVR). We previously described the Emory Risk Score (ERS) to predict the need for new pacemaker implant (PPM) after TAVR. Metrics included in the score are a history of syncope, pre-existing RBBB, QRS duration ≥140 ms, and prosthesis oversizing ≥16%. To prospectively validate the previously described risk score.<br /><b>Methods</b><br />We prospectively evaluated all patients without pre-existing pacemakers, ICD, or pre-existing indications for pacing undergoing TAVR with the Edwards SAPIEN 3 prosthesis at our institution from March 2019 to December 2020 (n = 661). Patients were scored prospectively; however, results were blinded from clinical decision-making. The primary endpoint was PPM at 30 days after TAVR. Performance of the ERS was evaluated using logistic regression, a calibration curve to prior performance, and receiver operating characteristic (ROC) analysis.<br /><b>Results</b><br />A total of 48 patients (7.3%) had PPM after TAVR. A higher ERS predicted an increased likelihood of PPM (OR 2.61, 95% CI: 2.05-3.25 per point, p < 0.001). There was good correlation between observed and expected values on the calibration curve (slope = 1.04, calibration at large = 0.001). The area under the ROC curve was 0.81 (95% CI [0.74-0.88], p < 0.001).<br /><b>Conclusions</b><br />The ERS prospectively predicted the need for PPM in a serial, real-world cohort of patients undergoing TAVR with a balloon-expandable prosthesis, confirming findings previously described in retrospective cohorts. Notably, the prospective performance of the score was comparable with that of the initial cohorts. The risk score could serve as a framework for preprocedural risk stratification for PPM after TAVR.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 13 Sep 2023; epub ahead of print</small></div>

<div><h4>Association of leadless pacing with ventricular and valvular function.</h4><i>Arps K, Li B, Allen JC, Alenezi F, ... Thomas KL, Piccini JP</i><br /><b>Background</b><br />Traditional transvenous pacemakers are associated with worsening tricuspid valve function due to lead-related leaflet impingement, as well as ventricular dysfunction related to electromechanical dyssynchrony from chronic right ventricular (RV) pacing. The association of leadless pacing with ventricular and valvular function has not been well established. We aimed to assess the association of leadless pacemaker placement with changes in valvular regurgitation and ventricular function.<br /><b>Methods and results</b><br />Echocardiographic features before and after leadless pacemaker implant were analyzed in consecutive patients who received a leadless pacemaker with pre- and postprocedure echocardiography at Duke University Hospital between November 2014 and November 2019. Valvular regurgitation was graded ordinally from 0 (none) to 3 (severe). Among 54 patients, the mean age was mean age was 70.1 ± 14.3 years, 24 (44%) were women, and the most frequent primary pacing indication was complete heart block in 24 (44%). The median RV pacing burden was 45.4 (interquartile range [IQR] 3.5-97.0). On echocardiogram performed 8.9 months (IQR 4.5-14.5) after implant, there was no change in the average severity of tricuspid regurgitation (mean change 0.07 ± 1.15, p = .64) from pre-procedure echocardiogram. We observed a decrease in the average left ventricular ejection fraction (LVEF) (52.3 ± 9.3 to 47.9 ± 12.1, p = .0019) and tricuspid annular plane systolic excursion (TAPSE) (1.8 ± 0.6 to 1.6 ± 0.4, p = .0437). Thirteen patients (24%) had absolute drop in LVEF of ≥10%.<br /><b>Conclusion</b><br />We did not observe short term worsening valvular function in patients with leadless pacemakers. However, consistent with the pathophysiologic impact of RV pacing, leadless pacing was associated with a reduction in biventricular function.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 13 Sep 2023; epub ahead of print</small></div>

<div><h4>The impact of age on ablation outcomes in AF-mediated cardiomyopathy.</h4><i>Segan L, Chieng D, Sugumar H, Voskoboinik A, ... Kistler PM, Prabhu S</i><br /><b>Introduction</b><br />The absence of ventricular scar in patients with atrial fibrillation (AF) and systolic heart failure (HF) predicts left ventricular (LV) recovery following AF ablation. It is unknown whether age impacts the degree of LV recovery, reverse remodeling, or AF recurrence following catheter ablation (CA) among this population.<br /><b>Objectives</b><br />To evaluate the impact of age on LV recovery and AF recurrence in a population with AF and systolic HF without fibrosis (termed AF-mediated cardiomyopathy) following CA.<br /><b>Methods</b><br />Consecutive patients undergoing CA between 2013 and 2021 with LV ejection fraction (LVEF) < 45% and absence of cardiac magnetic resonance imaging (CMR) detected LV myocardial fibrosis were stratified by age (<65 vs. ≥65 years). Following CA, participants underwent remote rhythm monitoring for 12 months with repeat CMR for HF surveillance.<br /><b>Results</b><br />The study population consisted of 70 patients (10% female, mean LVEF 33 ± 9%), stratified into younger (age < 65 years, 63%) and older (age ≥ 65 years, 37%) cohorts. Baseline comorbidities, LVEF (34 ± 9 vs. 33 ± 8 ≥65 years, p = .686), atrial and ventricular dimensions (left atrial volume index: 55 ± 21 vs. 56 ± 14 mL/m<sup>2</sup> age ≥ 65, p = .834; indexed left ventricular end-diastolic volume: 108 ± 40 vs. 104 ± 28 mL/m<sup>2</sup> age ≥ 65, p = .681), pharmacotherapy and ablation strategy (pulmonary vein isolation in all; posterior wall isolation in 27% vs. 19% age ≥ 65, p = .448; cavotricuspid isthmus in 9% vs. 11.5% age ≥ 65) were comparable (all p > .05) albeit a higher CHADS<sub>2</sub> VASc score in the older cohort (2.7 ± 0.9 vs. 1.6 ± 0.6 age < 65, p < .001).   Freedom from AF was comparable (hazard ratio: 0.65, 95% confidence interval: 0.38-1.48, LogRank p = .283) as was AF burden [0% (interquartile range, IQR: 0.0-2.1) vs. age ≥ 65: [0% (IQR 0.0-1.7), p = .516], irrespective of age. There was a significant improvement in LV systolic function in both groups (ΔLVEF + 21 ± 14% vs. +21 ± 12% age ≥ 65, p = .913), with LV recovery in the vast majority (73% vs. 69%, respectively, p = .759) at 13 (IQR: 12-16) months. This was accompanied by comparable improvements in functional status (New York Heart Association class p = .851; 6-min walk distance 50 ± 61 vs. 93 ± 134 m in age ≥ 65, p = .066), biomarkers (ΔN-terminal-pro brain natriuretic peptide -139 ± 246 vs. -168 ± 181 age ≥ 65,p = .629) and HF symptoms (Short Form-36 survey Δphysical component summary p = .483/Δmental component summary, p = .841).<br /><b>Conclusion</b><br />In patients undergoing CA for AF with systolic HF in the absence of ventricular scar, comparable improvements in ventricular function, symptoms, and freedom from AF are achieved irrespective of age.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 11 Sep 2023; epub ahead of print</small></div>

<div><h4>Observations of interventricular septal behavior during left bundle branch pacing.</h4><i>Ponnusamy SS, Ganesan V, Anand V, Vadivelu R, ... Murugan S, Vijayaraman P</i><br /><b>Introduction</b><br />Left bundle branch pacing (LBBP) involves the deployment of the lead deep inside the septum. Penetration of the septum by the lead depends on the texture of the septum, rapidity of rotations, operator experience, and implantation tools.<br /><b>Objectives</b><br />The aim of our study was to assess the behavior of the lumenless lead during rapid rotations and the physiological property of the interventricular septum(IVS) during LBBP.<br /><b>Methods</b><br />Patients undergoing LBBP between January 2021 and December 2022 were retrospectively included in the study.<br /><b>Results</b><br />Among 255 attempted patients, 20 (7.9%) had procedural failure(no LBB capture-four, inability to penetrate septum-seven, and dislodgements after sheath removal-nine). Septal penetration achieved in 248/255 patients (97.2%). Lead movement inside the IVS was assessed by lead traverse time. Based on the behavior of the IVS (n = 255), three different responses were noted. Type-I response(normal/firm septum) in 93.7% (n = 239) characterized by constant and progressive movement of lead. Neither perforation nor further change in premature-ventricular-complex morphology beyond M-beat were observed despite additional few unintentional rotations indicating the protective mechanism of LV-endocardium. Type-II response(soft/cheesy septum) in 3.5% (n = 9) characterized by hyper-movement of lead without resistance due to altered texture of septum and poor LV subendocardial barrier resulting in perforation. No patients in this group had LV dysfunction or associated coronary artery disease. In type-III response, seen in 2.8% (n = 7), lead could not be penetrated due to scar in IVS.<br /><b>Conclusion</b><br />Three different patterns of responses were observed during LBBP. The most distinct type-ll response was associated with soft/cheesy septum with hyper-movement of the lead predisposing for future dislodgments in patients without structural heart disease.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 11 Sep 2023; epub ahead of print</small></div>

<div><h4>Guiding ablation strategies for ventricular tachycardia in patients with structural heart disease by analyzing links and conversion patterns of traceable abnormal late potential zone.</h4><i>Song X, Que D, Zhu Y, Yu W, ... Cai Y, Yang P</i><br /><b>Background</b><br />Substrate-based ablation can treat uninducible or hemodynamically instability scar-related ventricular tachycardia (VT). However, whether a correlation exists between the critical VT isthmus and late activation zone (LAZ) during sinus rhythm (SR) is unknown.<br /><b>Objective</b><br />To demonstrate the structural and functional properties of abnormal substrates and analyze the link between the VT circuit and abnormal activity during SR.<br /><b>Methods</b><br />Thirty-six patients with scar-related VT (age, 50.0 ± 13.7 years and 86.1% men) who underwent VT ablation were reviewed. The automatic rhythmia ultrahigh resolution mapping system was used for electroanatomic substrate mapping. The clinical characteristics and mapping findings, particularly the LAZ characteristics during SR and VT, were analyzed. To determine the association between the LAZ during the SR and VT circuits, the LAZ was defined as five activation patterns: entrance, exit, core, blind alley, and conduction barrier.<br /><b>Results</b><br />Forty-five VTs were induced in 36 patients, 91.1% of which were monomorphic. The LAZ of all patients was mapped during the SR and VT circuits, and the consistency of the anatomical locations of the LAZ and VT circuits was analyzed. Using the ultrahigh resolution mapping system, interconversion patterns, including the bridge, T, puzzle, maze, and multilayer types, were identified. VT ablation enabled precise ablation of abnormal late potential conduction channels.<br /><b>Conclusion</b><br />Five interconversion patterns of the LAZ during the SR and VT circuits were summarized. These findings may help formulate more precise substrate-based ablation strategies for scar-related VT and shorter procedure times.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 11 Sep 2023; epub ahead of print</small></div>

<div><h4>Impact of intracardiac echocardiography usage on the safety of cryoballoon atrial fibrillation ablation: Subanalysis of the prospective FREEZE cluster cohort study.</h4><i>Pongratz J, Kuniss M, Wu L, Tebbenjohanns J, ... Straube F, FREEZE Cohort Study Investigators</i><br /><b>Introduction</b><br />Cryoballoon ablation (CBA) aiming at pulmonary vein isolation (PVI) became a standardized atrial fibrillation (AF) ablation procedure. Life-threatening complications like cardiac tamponade exist. Intracardiac echocardiography (ICE) usage is associated with superior safety in radiofrequency ablation. It is unclear if ICE has an impact on safety of CBA.<br /><b>Methods</b><br />The FREEZE Cohort (NCT01360008) subanalysis included patients undergoing \"PVI only\" CBA. Patients with intraprocedural transesophageal echocardiography were excluded. Group A comprises conventional, group B ICE-guided CBA. Periprocedural results were compared.<br /><b>Results</b><br />From 2011 to 2016, a total of 4189 patients were enrolled, and 1906 (45.5%) were included in this subanalysis, split up in two groups (A: 1066 [55.9%], B: 840 [44.1%]). Group A was younger (60.6 ± 10.8 vs. 62.4 ± 10.5 years, p < .001), with smaller left atria (41 vs. 43 mm, p < .001), and less persistent AF (23.1 vs. 38.1%, p < .001). Procedure, left atrial, and fluoroscopy times were shorter in group A as compared to group B. Dose area product was significantly higher in group A (2911 vs. 2072 cGyxcm<sup>2</sup> , p < .001). In-hospital major adverse cerebrovascular and cardiac event rates including two deaths in group A were not different between groups (0.5% vs. 0.1%, p = .18). The rate of total procedural (10.4% vs. 5.1%, p < .001) and major complications (3.2% vs. 1.3%, p < .001) was significantly higher in group A. Cardiac tamponade occurred significantly more frequently in group A (8 [0.8%] vs. 1 [0.1%], p = .046). Independent predictors for major complications were female sex (odds ratio [OR] 2.03, p = .03) and non-ICE usage (OR 2.38, p = .02). No differences were observed for persistent phrenic nerve palsy, nor for groin complications.<br /><b>Conclusion</b><br />CBA was significantly safer and required less radiation if ICE was used, although the procedures were more complex. The risk of groin complications was not increased with ICE usage. Non-ICE usage was the only modifiable independent predictor of major complications.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 08 Sep 2023; epub ahead of print</small></div>

<div><h4>Comparison of pulsed field ablation and cryoballoon ablation for pulmonary vein isolation.</h4><i>Schipper JH, Steven D, Lüker J, Wörmann J, ... Pavel F, Sultan A</i><br /><b>Introduction</b><br />Pulmonary vein isolation (PVI) remains the cornerstone in the treatment of atrial fibrillation (AF). PVI using cryoballoon (CB) technology has emerged as a standard procedure in many centers. Recently, pulsed field ablation (PFA) has been introduced and used to achieve PVI. First data show high acute and favorable long-term outcomes. So far, data comparing these new \"single shot\" devices are sparse. We sought to compare procedural and outcome data for first time PFA users versus CB in patients undergoing de novo PVI. Furthermore, potentially postprocedural discomfort and affection of autonomic ganglia were assessed.<br /><b>Methods and results</b><br />A retrospective analysis and comparison of all de novo PVIs with PFA and CB was performed. Furthermore, PFA PVI learning curve was evaluated. During follow-up, repeat outpatient visits and Holter electrocardiogram were performed to analyze arrhythmia-free survival. Discomfort analysis was obtained by prescribed analgesic medication within first 48 h after PVI. Potential changes in heart rate (HR) between baseline and at 3-month follow-up were evaluated. A total of 108 patients (54 PFA and 54 CB; PFA; 33 (30%) female) with paroxysmal and persistent AF were analyzed. Type of AF was comparable (Patients suffering from PAF: PFA: 16 (30%), CB: 17 (31%), p = 1.0). In 107 (99%) patients, successful PVI was achieved. Transient phrenic palsy omitted complete PVI in one CB patient. A trend for a shorter overall procedure duration was observed in the PFA group (PFA: 64.5 ± 17.5 min; CB: 73.0 ± 24.8 min; p = 0.07). Excluding LA mapping time (first 14 cases), procedure time was significantly shorter using PFA (PFA: 58.0 ± 12.5 min, CB: 73.0 ± 24.8 min, p = 0.0001). Fluoroscopy time was significantly longer for PFA (PFA: 15.3 ± 4.7 min, CB: 12.3 ± 5.3 min; p = 0.001), but significantly less contrast medium was used (PFA: 12 ± 6 mL; CB: 51 ± 29 mL, p < 0.0001). Subgroup analysis of the PFA group revealed a significant shortening of procedure duration over time (first tertile: 72.7 ± 13.5 min, second tertile: 67.3 ± 21.7 min, third tertile: 53.4 ± 9.8 min, first vs. third tertile p < 0.0001). Two cardiac tamponades occurred in the PFA group (p = 0.495), of which one was most likely related to complex transseptal puncture. In the first 48 h after PVI, the number of prescribed analgesics due to postprocedural pain was equal between both groups (PFA: 7 (13%) patients, CB: 10 (19%) patients, p = 0.598). After a FU of 273 ± 129 days, 35 of 47 patients (74%) after PFA and 36 of 50 patients (72%) after CB PVI were free of any atrial arrhythmia (HR: 0.98, p = 0.88). Only in the PFA group, a significant increase in HR 3 months after PVI was observed (pre-PVI: 61 ± 8 beats/min, post-PVI: 65 ± 9 beats/min, p = 0.008).<br /><b>Conclusion</b><br />The new PFA technology is equally effective and safe as compared to CB for complete PVI with potentially shorter procedure time and significantly less contrast medium. However, AF recurrence rates after PFA PVI seem to be comparable to CB PVI.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 08 Sep 2023; epub ahead of print</small></div>

<div><h4>Improved cerebral blood flow and hippocampal blood flow in stroke-free patients after catheter ablation of atrial fibrillation.</h4><i>Hashimoto N, Arimoto T, Koyama K, Kutsuzawa D, ... Watanabe T, Watanabe M</i><br /><b>Introduction</b><br />Atrial fibrillation (AF) is a risk factor for reduced cerebral blood flow (CBF) and cognitive dysfunction, even in stroke-free patients. We aimed to test the hypothesis that CBF and hippocampal blood flow (HBF), measured with arterial spin labeling magnetic resonance imaging (MRI), improve after catheter ablation of AF to achieve sinus rhythm (SR).<br /><b>Methods</b><br />A total of 84 stroke-free patients (63.1 ± 9.1 years; paroxysmal AF, n = 50; non-paroxysmal AF, n = 34) undergoing AF catheter ablation were included. MRI studies were done before, 3 months, and 12 months after the procedure with CBF and HBF measurements.<br /><b>Results</b><br />Baseline CBF and HBF values in 50 paroxysmal AF patients were used as controls. Baseline CBF was higher in patients with paroxysmal AF than with non-paroxysmal AF (100 ± 32% vs. 86 ± 28%, p = .04). Patients with non-paroxysmal AF had increased CBF 3 months after AF ablation (86 ± 28% to 99 ± 34%, p = .03). Differences in CBF and HBF were greater in the group with AF restored to SR (p < .01). Both CBF and HBF levels at 12 months were unchanged from the 3 months level. Successful rhythm control by catheter ablation was an independent predictor of an increase in CBF > 17.5%. The Mini-Mental State Examination score improved after ablation (p = .02).<br /><b>Conclusion</b><br />SR restoration with catheter ablation was associated with improved CBF and HBF at 3 months, maintenance of blood flow, and improved cognitive function at 12 months.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 08 Sep 2023; epub ahead of print</small></div>

<div><h4>Myocardial scarring and recurrence of ventricular arrhythmia in patients surviving an out-of-hospital cardiac arrest.</h4><i>Thomsen AF, Winkel BG, Golvano LCC, Porta-Sánchez A, ... Roca-Luque I, Jacobsen PK</i><br /><b>Introduction</b><br />Prediction of recurrent ventricular arrhythmia (VA) in survivors of an out-of-hospital cardiac arrest (OHCA) is important, but currently difficult. Risk of recurrence may be related to presence of myocardial scarring assessed with late gadolinium enhancement cardiac magnetic resonance (LGE-CMR). Our study aims to characterize myocardial scarring as defined by LGE-CMR in survivors of a VA-OHCA and investigate its potential role in the risk of new VA events.<br /><b>Methods</b><br />Between 2015 and 2022, a total of 230 VA-OHCA patients without ST-segment elevation myocardial infarction had CMR before implantable cardioverter-defibrillator implantation for secondary prevention at Copenhagen University Hospital, Rigshospitalet, and Hospital Clínic, University of Barcelona, of which n = 170 patients had a conventional (no LGE protocol) CMR and n = 60 patients had LGE-CMR (including LGE protocol). Scar tissue including core, border zone (BZ) and BZ channels were automatically detected by specialized investigational software in patients with LGE-CMR. The primary endpoint was recurrent VA.<br /><b>Results</b><br />After exclusion, n = 52 VA-OHCA patients with LGE-CMR and a mean left ventricular ejection fraction of 49 ± 16% were included, of which 18 (32%) patients reached the primary endpoint of VA. Patients with recurrent VA in exhibited greater scar mass, core mass, BZ mass, and presence of BZ channels compared with patients without recurrent VA. The presence of BZ channels identified patients with recurrent VA with 67% sensitivity and 85% specificity (area under the ROC curve (AUC) 0.76; 95% CI: 0.63-0.89; p < .001) and was the strongest predictor of the primary endpoint.<br /><b>Conclusions</b><br />The presence of BZ channels was the strongest predictor of recurrent VA in patients with an out of-hospital cardiac arrest and LGE-CMR.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 08 Sep 2023; epub ahead of print</small></div>

<div><h4>Limits of the spatial ventricular gradient and QRST angles in patients with normal electrocardiograms and no known cardiovascular disease stratified by age, sex, and race.</h4><i>Stabenau HF, Sau A, Kramer DB, Peters NS, Ng FS, Waks JW</i><br /><b>Introduction</b><br />Measurement of the spatial ventricular gradient (SVG), spatial QRST angles, and other vectorcardiographic measures of myocardial electrical heterogeneity have emerged as novel risk stratification methods for sudden cardiac death and other adverse cardiovascular events. Prior studies of normal limits of these measurements included primarily young, healthy, White volunteers, but normal limits in older patients are unknown. The influence of race and body mass index (BMI) on these measurements is also unclear.<br /><b>Methods</b><br />Normal 12-lead electrocardiograms (ECGs) from a single center were identified. Patients with abnormal cardiovascular, pulmonary, or renal history (assessed by International Classification of Disease [ICD-9/ICD-10] codes) or abnormal cardiovascular imaging were excluded. The SVG and QRST angles were measured and stratified by age, sex, and race. Multivariable linear regression was used to assess the influence of age, BMI, and heart rate (HR) on these measurements.<br /><b>Results</b><br />Among 3292 patients, observed ranges of SVG and QRST angles (peak and mean) differed significantly based on sex, age, and race. Sex differences attenuated with increasing age. Men tended to have larger SVG magnitude (60.4 [46.1-77.8] vs. 52.5 [41.3-65.8] mv*ms, p < .0001) and elevation, and more anterior/negative SVG azimuth (-14.8 [-25.1 to -4.3] vs. 1.3 [-9.8 to 10.5] deg, p < .0001) compared to women. Men also had wider QRST angles. Observed ranges varied significantly with BMI and HR. SVG and QRST angle measurements were robust to different filtering bandwidths and moderate fiducial point annotation errors, but were heavily affected by changes in baseline correction.<br /><b>Conclusions</b><br />Age, sex, race, BMI, and HR significantly affect the range of SVG and QRST angles in patients with normal ECGs and no known cardiovascular disease, and should be accounted for in future studies. An online calculator for prediction of these \"normal limits\" given demographics is provided at https://bivectors.github.io/gehcalc/.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 08 Sep 2023; epub ahead of print</small></div>

<div><h4>Adverse events associated with amplatzer left atrial appendage occlusion delivery system: A Food and Drug Administration MAUDE database study.</h4><i>Kewcharoen J, Shah K, Bhardwaj R, Contractor T, ... Lakkireddy D, Garg J</i><br /><b>Background</b><br />Dual occlusive closure mechanism (disc and lobe type), Amulet device (Abbott; a second-generation device that has replaced Amplatzer Cardiac Plug) was approved by the Food and Drug Administration (FDA) in August 2021 for percutaneous left atrial appendage occlusion (LAAO). However, real-world safety data on the delivery system (Amplatzer Cardiac Plug and Amplatzer Amulet device) are lacking.<br /><b>Objective</b><br />We sought to assess the type of adverse events associated with the Amplatzer LAAO delivery system using the FDA Manufacturer and User Facility Device Experience (MAUDE) database.<br /><b>Methods</b><br />A MAUDE database search was conducted on March 31, 2023, for reports received between February 2013 and March 2023 to capture all adverse events.<br /><b>Results</b><br />A total of 59 adverse events were reported, of which 58 were sheath-related events, and one was a wire-related event. The most commonly encountered issue was air embolism (19%, 11 events), followed by sheath thrombosis (13.8%, eight events, two of which were also associated with device thrombosis), kinked sheath (10.3%, six events), and sheath deformation (8.6%, five events). Patient-related adverse events included pericardial effusion requiring pericardiocentesis (22.4%, 13 events), vascular complications (20.7%, 12 events), and device dislodgement (5.2%, three events).<br /><b>Conclusion</b><br />LAAO-related adverse events are increasingly being reported using the Amplatzer LAAO delivery sheath. It is anticipated that improvements in device technology, the advent of steerable sheaths, and operator experience will minimize these complications.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 07 Sep 2023; epub ahead of print</small></div>

<div><h4>Are antiarrhythmic agents indicated in premature ventricular complex-induced cardiomyopathy and when?</h4><i>Kantharia BK, Shah AN</i><br /><b>Introduction</b><br />Premature ventricular complexes (PVCs) are the most common ventricular arrhythmia that are encountered in the clinical practice. Recent data suggests that high PVC burden may lead to the development of PVC-induced cardiomyopathy (PVC-CM) even in patients without structural heart disease. Treatment for effective suppression of PVCs, can reverse PVC-CM. Both antiarrhythmic drugs (AADs) and catheter ablation (CA) are recognized treatment modalities for any cardiac arrhythmias. However, with increasing preference of CA, the role of AADs needs further defining regarding their efficacy, safety, indications and patient selection to treat PVC-CM.<br /><b>Methods</b><br />To ascertain the role of AADs to treat PVC-CM; whether they are indicated to treat PVC-CM, and if so, when, we interrogated PubMed and other search engines for English language publications with key words premature ventricular complexes (PVCs), cardiomyopathy, anti-arrhythmic drugs, catheter ablation, and pharmacological agents. All publications were carefully reviewed and scrutinized by the authors for their inclusion in the review paper. For illustration of cases, ethical standard was observed as per the 1975 Declaration of Helsinki, and the patient was treated as per the prevailing standard of care. Informed consent was obtained from the patient for conducting the ablation procedure.<br /><b>Results</b><br />Our literature search specifically the pharmacological treatment of PVC-CM with AADs revealed significant paradigm shift in treatment approach for PVCs and PVC-induced cardiomyopathy. No major large, randomized control trials of AADs versus CA for PVC-CM were found. We found that beta-blockers and calcium channel blockers are particularly effective in the treatment of PVCs originating from right ventricular outflow tract. For Class Ic AADs - flecainide and propafenone, small clinical studies showed Class Ic AADs to be effective in PVC suppression, but their usage was not recommended in patients with significant coronary artery disease. Mexiletine was found to have modest effect on PVC suppression. Studies showed sotalol to significantly reduce PVCs frequency in patients receiving both low and high doses. Studies also showed amiodarone to have higher successful PVC suppression, but not recommended as a first-line treatment for patients with idiopathic PVCs in the absence of symptoms and left ventricular dysfunction. For dronedarone, no major clinical data were available.<br /><b>Conclusions</b><br />Based on the available data in the literature, we conclude that AADs play important role in the treatment of PVC-induced cardiomyopathy. However, appropriate patient selection criteria are vitally important, and in general terms AADs are indicated or polymorphic PVCs, epicardial PVCs; and when CA procedure is contraindicated, or not feasible or failed.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 07 Sep 2023; epub ahead of print</small></div>

<div><h4>Athletes and suspected catecholaminergic polymorphic ventricular tachycardia: Awareness and current knowledge.</h4><i>Mascia G, Brugada J, Arbelo E, Porto I</i><br /><b>Introduction</b><br />Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a cardiac inherited arrhythmogenic disease potentially leading to sudden cardiac death that is determined by electrical instability exacerbated by acute adrenergic tone.<br /><b>Methods and results</b><br />Despite its life-threatening nature, CPVT remains potentially unnoticed since diagnosis may be difficult especially in apparently healthy athletes. This review summarizes current knowledge and shortcomings of CPVT, focusing on genetics, arrhythmic mechanisms, sport preparticipation screening, and current recommendations.<br /><b>Conclusions</b><br />The paper captures the importance of CPVT athletes regarding the necessity of risk stratification, as well as the importance of maintaining a healthy lifestyle.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 01 Sep 2023; epub ahead of print</small></div>

<div><h4>Catheter-induced right bundle branch block: Practical implications for the cardiac electrophysiologist.</h4><i>Ali H, Lupo P, Foresti S, De Ambroggi G, ... Cristiano E, Cappato R</i><br /><AbstractText>The right bundle branch (RBB), due to its endocardial course, is susceptible to traumatic block caused by \"bumping\" during right-heart catheterization. In the era of cardiac electrophysiology, catheter-induced RBB block (CI-RBBB) has become a common phenomenon observed during electrophysiological studies and catheter ablation procedures. While typically transient, it may persist for the entire procedure time. Compared to pre-existing RBBB, the transient nature of CI-RBBB allows for comparative analysis relative to the baseline rhythm. Furthermore, unlike functional RBBB, it occurs at similar heart rates, making the comparison of conduction intervals more reliable. While CI-RBBB can provide valuable diagnostic information in various conditions, it is often overlooked by cardiac electrophysiologists. Though it is usually a benign and self-limiting conduction defect, it may occasionally lead to diagnostic difficulties, pitfalls, or undesired consequences. Avoidance of CI-RBBB is advised in the presence of baseline complete left bundle branch block and when approaching arrhythmic substrates linked to the right His-Purkinje-System, such as fasciculo-ventricular pathways, bundle branch reentry, and right-Purkinje focal ventricular arrhythmias. This article aims to provide a comprehensive practical review of the electrophysiological phenomena related to CI-RBBB and its impact on the intrinsic conduction system and various arrhythmic substrates.</AbstractText><br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 01 Sep 2023; epub ahead of print</small></div>

<div><h4>Unipolar and bipolar electrograms to predict successful ablation site of premature ventricular contractions originating from the free wall of the tricuspid annulus.</h4><i>Liu QF, Tian Y, Tian LH, Jing H</i><br /><b>Introduction</b><br />This study aimed to identify the characteristics of unipolar and bipolar electrogram (UniEGM and BiEGM) in guiding successful ablation of premature ventricular contractions (PVCs) originating from the free wall of the ventricular aspect of the tricuspid annulus (TA). We hypothesized that the negative concordance pattern (NCP) on the onset of UniEGM and BiEGM, together with the least value of the difference between the earliest BiEGM and UniEGM dV/dTmax, might improve the accuracy of conventional mapping.<br /><b>Methods and results</b><br />Thirty consecutive patients who underwent successful catheter ablation from February 2018 to July 2021 were retrospectively analyzed. The BiEGM and UniEGM for successful ablation sites were compared with those for non-successful ablation sites. Among the 30 patients, 30 successful and 26 nonsuccessful ablation sites were compared. The earliest activation time of the BiEGM (BiEGMoneset-QRS) was 25 ± 6 ms for the successful ablation sites and 21 ± 6 ms for the nonsuccessful ablation sites (p = .47). The value of the difference in the earliest BiEGM and UniEGM dV/dTmax differed between successful and nonsuccessful ablation sites (6.4 ± 3.6 ms vs. 10.4 ± 6.8 ms). NCP was observed at 90.0% and 42.3% of the successful and nonsuccessful ablation sites, respectively. Alignment of NCP and BiEGMonset-UniEGM ≤6 ms was applied as the mapping criterion for successful PVC suppression (73.1% sensitivity and 87.7% specificity). The area under the receiver-operating characteristic curve for this cutoff was 0.85.<br /><b>Conclusion</b><br />Mapping based on an NCP at the onset of the BiEGM and UniEGM and the least difference value of the earliest BiEGM and UniEGM dV/dTmax had an excellent predictive value for successful ablation. These strategies may reduce the number of radiofrequency catheter ablation (RFCA) applications for free-wall tricuspid annular PVCs.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 26 Aug 2023; epub ahead of print</small></div>

<div><h4>Tailored ablation index based on left atrial wall thickness assessed by computed tomography for pulmonary vein isolation in patients with atrial fibrillation.</h4><i>Lee SR, Park HS, Kwon S, Choi EK, Oh S</i><br /><b>Introduction</b><br />Although left atrial wall thickness (LAWT) is known to be varied, a fixed target Ablation Index (AI) based pulmonary vein isolation (PVI) has been suggested in catheter ablation for atrial fibrillation (AF). We aimed to evaluate the efficacy and safety of PVI applying tailored AI based on LAWT assessed by cardiac computed tomography (CT).<br /><b>Methods</b><br />The thick segment was defined as the segment including ≥LAWT grade 3 (≥1.5 mm). The fixed AI strategy was defined as AI targets were 450 on the anterior/roof segments and 350 on the posterior/inferior/carina segments regardless of LAWT. The tailored AI strategy consisted of AI increasing the targets to 500 on the anterior/roof segments and to 400 on the posterior/inferior/carina segments when ablating the thick segment. After PVI, acute pulmonary vein (PV) reconnection, defined by the composite of residual potential and early reconnection, was evaluated.<br /><b>Results</b><br />A total of 156 patients (paroxysmal AF 72%) were consecutively included (86 for the fixed AI group and 70 for the tailored AI group). The tailored AI group showed a significantly lower rate of segments with acute PV reconnection than the fixed AI group (8% vs. 5%, p = .007). The tailored AI group showed a trend for shorter ablation time for PVI. One-year AF/atrial tachycardia free survival rate was similar in two groups (87.2% in the fixed AI group and 90.0% in the tailored AI group, p = .606).<br /><b>Conclusion</b><br />Applying tailored AI based on the LAWT was a feasible and effective strategy to reduce acute PV reconnection after PVI.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 18 Aug 2023; epub ahead of print</small></div>

<div><h4>Efficacy of 3D-multidetector computed tomography and fluoroscopy fusion for percutaneous left atrial appendage occlusion procedures.</h4><i>Carneiro HA, Dallan LAP, Yoon SH, Arora S, ... Rashid I, Filby SJ</i><br /><b>Introduction</b><br />We studied the impact of the use of three-dimensional multidetector computed tomography (3D-MDCT) and fluoroscopy fusion on percutaneous left atrial appendage occlusion (LAAO) procedures in relation to procedure time, contrast volume, fluoroscopy time, and total radiation.<br /><b>Methods</b><br />This was a single-center, prospective, single-blinded, randomized control trial. Patients meeting criteria for LAAO were randomized to undergo LAAO with the WATCHMAN FLX<sup>TM</sup> device with and without 3D-MDCT-fluoroscopy fusion guidance using a prespecified protocol using computed tomography angiography for WATCHMAN FLX<sup>TM</sup> sizing, moderate sedation, and intracardiac echocardiography for procedural guidance.<br /><b>Results</b><br />Overall, 59 participants were randomly assigned to the fusion (n = 33) or no fusion (n = 26) groups. The median (interquartile range) age was 79 (75-83) years, 24 (41%) were female, and 55 (93%) were Caucasian. The median CHA<sub>2</sub> DS<sub>2</sub> VASc and HASBLED scores were 5 (4-6) and 3 (3-4), respectively. At the time of the study, 51 (53%) patients were on a direct acting oral anticoagulant. There were no significant differences between the fusion and no fusion groups in procedure time (52.4 ± 15.4 vs. 56.8 ± 19.5 min, p = .36), mean contrast volume used (33.8 ± 12.0 vs. 29.6 ± 11.5 mls, p = .19), mean fluoroscopy time (31.3 ± 9.9 vs. 28.9 ± 8.7 min, p = .32), mean radiation dose (1177 ± 969 vs. 1091 ± 692 mGy, p = .70), and radiation dose product curve (23.9 ± 20.5 vs. 35.0 ± 49.1 Gy cm<sup>2</sup> , p = .29). There was no periprosthetic leak in the two groups in the immediate 1-month postprocedure follow-up periods.<br /><b>Conclusions</b><br />There was no significant difference with and without 3D-MDCT-fluoroscopy fusion in procedure time, contrast volume use, radiation dose, and radiation dose product.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 17 Aug 2023; epub ahead of print</small></div>

<div><h4>Wire ThRoUgh Snare Twice (Wire TRUST) technique: A novel method to grasp a lead with inaccessible ends as a supportive femoral approach for transvenous lead extraction.</h4><i>Kasai Y, Haraguchi T, Morita J, Kitai T, ... Kasai J, Fujita T</i><br /><b>Introduction</b><br />Transvenous lead extraction (TLE) is a crucial procedure for managing cardiac implantable electronic devices. The use of a combined superior and femoral approach has been found to enhance the success rate of TLE. This report introduces a novel technique, named \"Wire ThRoUgh Snare Twice\" (Wire TRUST), for effectively grasping a lead without a free end during TLE.<br /><b>Method</b><br />The Wire TRUST technique was applied in a case involving a 49-year-old male patient requiring TLE due to electrical artifact on the right ventricular (RV) lead, replacement of the RV lead, and pacemaker generator exchange. The Wire TRUST technique involved the insertion of a 4-Fr pigtail catheter and a 6-Fr snare catheter through the 14-Fr sheath inserted from the right common femoral vein. The 4-Fr pigtail catheter was hooked to the RV lead under multidirectional fluoroscopic guidance in the right atrium. The 0.014-in. guidewire was advanced through the pigtail catheter, crossing the RV lead until reaching the inferior vena cava. Subsequently, the distal end of the 0.014-in. guidewire was captured using a snare and pulled, facilitating externalization of the guidewire. After externalization, both ends of the 0.014-in. guidewire were passed through the snare outside the body and reinserted into the 14-Fr sheath. By simultaneously advancing and closing the snare while applying tension to the 0.014-in. guidewire, a secure grip on the lead without free ends was achieved.<br /><b>Results</b><br />The Wire TRUST technique enabled successful lead extraction and replacement without any complications. The technique facilitated the co-axial alignment of the powered sheath with the RV lead, ensuring safe and efficient extraction.<br /><b>Conclusion</b><br />The Wire TRUST technique presents a novel and effective approach for grasping leads with inaccessible ends during TLE.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 14 Aug 2023; epub ahead of print</small></div>

<div><h4>Value of genotyping and scar-phenotyping for VT ablation procedures in patients with nonischemic left ventricular cardiomyopathies.</h4><i>Kovacs B, Ghannam M, Liang J, Moccoro E, ... Morady F, Bogun F</i><br /><b>Introduction</b><br />Variants of cardiomyopathy genes in patients with nonischemic cardiomyopathy (NICM) generate various phenotypes of cardiac scar and delayed enhancement cardiac magnetic resonance (DE-CMR) imaging which may impact ventricular tachycardia (VT) management.<br /><b>Methods</b><br />The objective was to compare the findings of cardiomyopathy genetic testing on DE-CMR imaging and long-term outcomes among patients with NICM undergoing VT ablation procedures. Image phenotyping and genotyping were performed in a consecutive series of patients referred for VT ablation and correlated to survival free of VT. Scar depth index (SDI) (% of scar at 0-3 mm, 3-5 mm and >5 mm projected on the closest endocardial surface) was determined.<br /><b>Results</b><br />Forty-three patients were included (11 women, 55 ± 14 years, ejection fraction (EF) 45 ± 16%) and were followed for 3.4 ± 2.9 years. Pathogenic variants (PV) were identified in 16 patients (37%) in the following genes: LMNA (n = 5), TTN (n = 5), DSP (n = 2), AMLS1 (n = 1), MYBPC3 (n = 1), PLN (n = 1), and SCN5A (n = 1). A ring-like septal scar (RLSS) pattern was more often seen in patients with pathogenic variants (66% vs 15%, p = .001). RLSS was associated with deeper seated scars (SDI >5 mm 30.6 ± 22.6% vs 12.4 ± 16.2%, p = .005), and increased VT recurrence (HR 5.7 95% CI[1.8-18.4], p = .003). After adjustment for age, sex, EF, and total scar burden, the presence of a PV remained independently associated with worse outcomes (HR 4.7 95% CI[1.22-18.0], p = .02).<br /><b>Conclusions</b><br />Preprocedural genotyping and scar phenotyping is beneficial to identify patients with a favorable procedural outcome. Some PVs are associated with an intramural, deeper seated scar phenotype and have an increase of VT recurrence after ablation.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 14 Aug 2023; epub ahead of print</small></div>

<div><h4>Practical and systematic approach using the steerable catheter and stylet-driven lead to deliver safe and effective left bundle branch area pacing.</h4><i>Foo D, Tan K, Ng S, Tan LW, Chia PL</i><br /><b>Introduction</b><br />Current delivery tools were not designed for left bundle branch area pacing (LBBAP). Challenges using these tools include lack of reach into the right ventricle and poor support for the lead to penetrate the interventricular septum. Concerns using stylet-driven leads (SDL) for LBBAP have been previously highlighted. Knowledge and the technical know-how of using SDL for LBBAP need to be evaluated in a fair and consistent manner. A stepwise approach is devised for use of Agilis HisPro<sup>TM</sup> steerable catheter with Tendril STS Model 2088TC lead for LBBAP and evaluated for safety and reproducibility.<br /><b>Methods</b><br />Consecutive patients undergoing LBBAP using the stepwise approach with Agilis HisPro<sup>TM</sup> steerable catheter were analyzed. The safety, efficacy and reproducibility of the technique were evaluated. The lead parameters were analyzed in the immediate (1 day) and short-term period (3-6 months) post implantation.<br /><b>Results</b><br />LBBAP was attempted in 41 patients using the stepwise approach of which 37 (90.7%) were successful. The lead parameters were stable in the immediate and short-term post implantation in all our patients. There was no significant difference between the group of patients with multiple repositioning of the lead compared to those successful at the 1st attempt. There were no acute or short-term lead and procedural complications.<br /><b>Conclusion</b><br />A stepwise and systematic approach using the Agilis HisPro<sup>TM</sup> steerable catheter and proper handling of the Tendril STS Model 2088TC stylet-driven lead is an important part of the armamentarium to deliver LBBAP in a practical, effective and reproducible manner.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 10 Aug 2023; epub ahead of print</small></div>

<div><h4>Endomyocardial substrate of ventricular arrhythmias in patients with autoimmune rheumatic diseases.</h4><i>Reithmann C, Kling T, Metani M, Klingel K, Ulbrich M</i><br /><b>Introduction</b><br />Delayed enhancement-magnetic resonance imaging (DE-MRI) has demonstrated that nonischemic cardiomyopathy is mainly characterized by intramural or epicardial fibrosis whereas global endomyocardial fibrosis suggests cardiac involvement in autoimmune rheumatic diseases or amyloidosis. Conduction disorders and sudden cardiac death are important manifestations of autoimmune rheumatic diseases with cardiac involvement but the substrates of ventricular arrhythmias in autoimmune rheumatic diseases have not been fully elucidated.<br /><b>Methods and results</b><br />20 patients with autoimmune rheumatic diseases presenting with ventricular tachycardia (VT) (n = 11) or frequent ventricular extrasystoles (n = 9) underwent DE-MRI and/or endocardial electroanatomical mapping of the left ventricle (LV). Ten patients with autoimmune rheumatic diseases underwent VT ablation. Global endomyocardial fibrosis without myocardial thickening and unrelated to coronary territories was detected by DE-MRI or electroanatomical voltage mapping in 9 of 20 patients with autoimmune rheumatic diseases. In the other patients with autoimmune rheumatic diseases, limited regions of predominantly epicardial (n = 4) and intramyocardial (n = 5) fibrosis or only minimal fibrosis (n = 2) were found using DE-MRI. Endocardial low-amplitude diastolic potentials and pre-systolic Purkinje or fascicular potentials, mostly within fibrotic areas, were identified as the targets of successful VT ablation in 7 of 10 patients with autoimmune rheumatic diseases.<br /><b>Conclusion</b><br />Global endomyocardial fibrosis can be a tool to diagnose severe cardiac involvement in autoimmune rheumatic diseases and may serve as the substrate of ventricular arrhythmias in a substantial part of patients.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 09 Aug 2023; epub ahead of print</small></div>

<div><h4>Histopathological characteristics of the arrhythmogenic right ventricular cardiomyopathy presenting the electrocardiographic characteristics with Brugada syndrome.</h4><i>Murase Y, Igawa O, Imai H, Ogawa Y, ... Kawaguchi K, Kawaguchi K</i><br /><b>Introduction</b><br />The histopathological characteristics of the overlapping disease states of Brugada syndrome (BrS) and arrhythmogenic right ventricular cardiomyopathy (ARVC) have not been fully elucidated.<br /><b>Methods</b><br />A 71-year-old man showed coved-type ST-segment elevation with the right precordial leads, and the echocardiography demonstrated right ventricular (RV) dilatation. After 11 months, he died of a polymorphic VT storm.<br /><b>Results</b><br />The pathological tissue demonstrated fibrofatty degeneration in the free wall of the RV outflow tract based on the heart autopsy.<br /><b>Conclusion</b><br />The overlapping disease states of BrS and ARVC showed histopathological characteristics consistent with ARVC.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 09 Aug 2023; epub ahead of print</small></div>

<div><h4>Sex differences in clinical characteristics, management, and outcomes in patients admitted for ventricular tachycardia: 2016-2018.</h4><i>Prasitlumkum N, Chokesuwattanaskul R, Kaewput W, Thongprayoon C, ... Jongnarangsin K, Nademanee K</i><br /><b>Introduction</b><br />The concurrent data on sex disparities in VT management and outcomes have remained unclear. Therefore, our objective was to determine the impact of sex on ventricular tachycardia (VT) management and outcomes in patients admitted with VT, dervied from the US National Inpatient Sample database (NIS).<br /><b>Methods</b><br />We used data from the US NIS to identify hospitalized adult patients who were admitted with VT between 2016 and 2018. Regression analysis was conducted to evaluate the impact of sex on VT management, in-hospital mortality, complications, length of stay, and hospitalization costs.<br /><b>Results</b><br />Of the database, a total of 146 070 patients, who were primarily hospitalized for VT, were approximated. Among these, women comprised 25.5%; they were significantly younger and had fewer comorbidities. Of procedural aspects, women were less likely to receive an angiogram, mechanical support, implantable cardioverter-defibrillator implantation, and VT ablation compared to men. Notably, women were associated with higher do-not-resuscitate rates and in-hospital cardiac arrests than men. No differences in in-hospital mortality and cardiogenic shock were observed between men and women (p > .05). Length of stay was significantly longer for women, while no differences in hospital costs were observed in both sexes.<br /><b>Conclusion</b><br />Significant sex disparities in management and outcomes were observed in admitted patients with VT. Our results reflect the need for further studies to explore factors causing such diversities.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 09 Aug 2023; epub ahead of print</small></div>

<div><h4>Heart failure and atrial fibrillation: Is atrial fibrillation ablation in heart failure pointless or mandatory?</h4><i>Kantharia BK</i><br /><AbstractText>A vast amount of now well-established clinical and epidemiological data indicates a close, interdependent, and symbiotic association between atrial fibrillation (AF) and heart failure (HF). Both AF and HF, when co-exist in a patient, have serious treatment and prognostic implications. Based on the prevailing knowledge of the topic, various societies have issued a number of guidelines regarding the management of patients with AF and HF. Overall, it is the rhythm control strategy that has shown beneficial effect over the rate control strategy with improvement in symptoms of AF and HF. While antiarrhythmic drugs (AADs) and catheter ablation (CA) may be utilized as rhythm control strategy for AF, both AADs and CA have limitations of their own. Furthermore, with the progress made in various pharmacotherapeutic agents in HF, one could question the utility of CA in HF (i.e., whether ablation is mandatory or pointless in patients who have HF). The purpose of this review is to discuss this very point, focusing on the beneficial, neutral, or detrimental outcome of CA based on the category and class of HF.</AbstractText><br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 07 Aug 2023; epub ahead of print</small></div>

<div><h4>Left bundle branch area pacing for heart failure patients requiring cardiac resynchronization therapy: A meta-analysis.</h4><i>Jin C, Dai Q, Li P, Lam P, Cha YM</i><br /><b>Introduction</b><br />Left bundle branch area pacing (LBBP) is a novel conduction system pacing method to achieve effective physiological pacing and an alternative to cardiac resynchronization therapy (CRT) with biventricular pacing (BVP) for patients with heart failure with reduced ejection fraction (HFrEF). We conduted this meta-analysis and systemic review to review current data comparing BVP and LBBP in patients with HFrEF and indications for CRT.<br /><b>Methods</b><br />We searched PubMed/Medline, Web of Science, and Cochrane Library from the inception of the database to November 2022. All studies that compared LBBP with BVP in patients with HFrEF and indications for CRT were included. Two reviewers performed study selection, data abstraction, and risk of bias assessment. We calculated risk ratios (RRs) with the Mantel-Haenszel method and mean difference (MD) with inverse variance using random effect models. We assessed heterogeneity using the I<sup>2</sup> index, with I<sup>2</sup>  > 50% indicating significant heterogeneity.<br /><b>Results</b><br />Ten studies (9 observational studies and 1 randomized controlled trial; 616 patients; 15 centers) published between 2020 and 2022 were included. We observed a shorter fluoroscopy time (MD: 9.68, 95% confidence interval [CI]: 4.49-14.87, I<sup>2</sup>  = 95%, p < .01, minutes) as well as a shorter procedural time (MD 33.68, 95% CI: 17.80-49.55, I<sup>2</sup>  = 73%, p < .01, minutes) during the implantation of LBBP CRT compared to conventional BVP CRT. LBBP was shown to have a greater reduction in QRS duration (MD 25.13, 95% CI: 20.06-30.20, I<sup>2</sup>  = 51%, p < .01, milliseconds), a greater left ventricular ejection fraction improvement (MD: 5.80, 95% CI: 4.81-6.78, I<sup>2</sup>  = 0%, p < .01, percentage), and a greater left ventricular end-diastolic diameter reduction (MD: 2.11, 95% CI: 0.12-4.10, I<sup>2</sup>  = 18%, p = .04, millimeter). There was a greater improvement in New York Heart Association function class with LBBP (MD: 0.37, 95% CI: 0.05-0.68, I<sup>2</sup>  = 61%, p = .02). LBBP was also associated with a lower risk of a composite of heart failure hospitalizations (HFH) and all-cause mortality (RR: 0.48, 95% CI: 0.25-0.90, I<sup>2</sup>  = 0%, p = .02) driven by reduced HFH (RR: 0.39, 95% CI: 0.19-0.82, I<sup>2</sup>  = 0%, p = .01). However, all-cause mortality rates were low in both groups (1.52% vs. 1.13%) and similar (RR: 0.98, 95% CI: 0.21-4.68, I<sup>2</sup>  = 0%, p = .87).<br /><b>Conclusion</b><br />This meta-analysis of primarily nonrandomized studies suggests that LBBP is associated with a greater improvement in left ventricular systolic function and a lower rate of HFH compared to BVP. There was uniformity of these findings in all of the included studies. However, it would be premature to conclude based solely on the current meta-analysis alone, given the limitations stated. Dedicated, well-designed, randomized controlled trials and observational studies are needed to elucidate better the comparative long-term efficacy and safety of LBBP CRT versus BIV CRT.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 07 Aug 2023; epub ahead of print</small></div>

<div><h4>Dry suction water seal system for management of pericardial fluid during epicardial ablation.</h4><i>Powell B, Coons T, Lesiczka M, Markert C, Mehta R, Misra S</i><br /><b>Introduction</b><br />Epicardial ablation is an important approach in the management of patients with complex ventricular arrhythmias. Irrigated ablation catheters present a challenge in this potential space due to fluid accumulation that can cause hemodynamic compromise, requiring frequent manual fluid aspiration. In this series, we report our initial experience with the use of a dry suction water seal system for pericardial fluid management during epicardial ablation.<br /><b>Methods</b><br />Consecutive patients undergoing epicardial ventricular tachycardia (VT) ablation at a single center were included. All patients underwent epicardial access via a subxiphoid approach with a single operator. A deflectable sheath was advanced into the pericardial space, and the side port was attached to a dry suction water seal system attached to wall suction at -20 mmHg. Procedural information including patient characteristics, outcomes, and adverse events. After a period of initial experience, pericardial fluid infusion and aspiration volumes were recorded.<br /><b>Results</b><br />Eleven patients were included in this series. All patients underwent epicardial ablation with complete success achieved in 8 of the 11 patients and partial success in the remaining patients. Pericardial fluid intake ranging from 485 to 3050 mL with aspiration of 350-3050 mL using the dry suction water seal system. No adverse events occurred.<br /><b>Conclusion</b><br />Dry suction water seal drainage systems can provide a safe strategy for efficient pericardial fluid management during epicardial VT ablation, potentially shortening procedure duration.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 02 Aug 2023; epub ahead of print</small></div>

<div><h4>Nonprocedural bleeding after left atrial appendage closure versus direct oral anticoagulants: A subanalysis of the randomized PRAGUE-17 trial.</h4><i>Branny M, Osmancik P, Kala P, Poloczek M, ... Reddy VY, PRAGUE-17 Trial Investigators</i><br /><b>Introduction</b><br />Observational studies have shown low bleeding rates in patients with atrial fibrillation (AF) treated by left atrial appendage closure (LAAC); however, data from randomized studies are lacking. This study compared bleeding events among patients with AF treated by LAAC and nonvitamin K anticoagulants (NOAC).<br /><b>Methods</b><br />The Prague-17 trial was a prospective, multicenter, randomized trial that compared LAAC to NOAC in high-risk AF patients. The primary endpoint was a composite of a cardioembolic event, cardiovascular death, and major and clinically relevant nonmajor bleeding (CRNMB) defined according to the International Society on Thrombosis and Hemostasis (ISTH).<br /><b>Results</b><br />The trial enrolled 402 patients (201 per arm), and the median follow-up was 3.5 (IQR 2.6-4.2) years. Bleeding occurred in 24 patients (29 events) and 32 patients (40 events) in the LAAC and NOAC groups, respectively. Six of the LAAC bleeding events were procedure/device-related. In the primary intention-to-treat analysis, LAAC was associated with similar rates of ISTH major or CRNMB (sHR 0.75, 95% CI 0.44-1.27, p = 0.28), but with a reduction in nonprocedural major or CRNMB (sHR 0.55, 95% CI 0.31-0.97, p = 0.039). This reduction for nonprocedural bleeding with LAAC was mainly driven by a reduced rate of CRNMB (sHR for major bleeding 0.69, 95% CI 0.34-1.39, p = .30; sHR for CRNMB 0.43, 95% CI 0.18-1.03, p = 0.059). History of bleeding was a predictor of bleeding during follow-up. Gastrointestinal bleeding was the most common bleeding site in both groups.<br /><b>Conclusion</b><br />During the 4-year follow-up, LAAC was associated with less nonprocedural bleeding. The reduction is mainly driven by a decrease in CRNMB.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 02 Aug 2023; epub ahead of print</small></div>

<div><h4>Higher power achieves greater local impedance drop, shorter ablation time, and more transmural lesion formation in comparison to lower power in local impedance guided radiofrequency ablation of atrial fibrillation.</h4><i>Yamashita S, Mizukami A, Ono M, Hiroki J, ... Miyazaki S, Sasano T</i><br /><b>Background</b><br />Since the local impedance (LI) of the ablation catheter reflects tissue characteristics, the efficacy of higher power (HP) compared to lower power (LP) in LI-guided ablation may differ from other index-guided ablations.<br /><b>Objective</b><br />This study aimed to assess the efficacy of HP ablation in LI-guided ablation of atrial fibrillation (AF).<br /><b>Methods</b><br />A prospective observational study was conducted, enrolling patients undergoing de novo ablation for AF. Pulmonary vein isolation was performed using point-by-point ablation with a RHYTHMIA HDx<sup>TM</sup> Mapping System and an open-irrigated ablation catheter with mini-electrodes (IntellaNav MIFI OI). Ablation was stopped when the LI drop reached 30 ohms, three seconds after the LI plateaued, or when ablation time reached 30 s. To balance the baseline differences, a unique method was used in which the power was changed between HP (45 W to anterior wall/40 W to posterior wall) and LP (35 W/30 W) alternately for each adjacent point.<br /><b>Results</b><br />A total of 551 ablations in 10 patients were analyzed (HP, n = 276; LP, n = 275). The maximum LI drop was significantly larger (HP: 28.3 ± 5.4 vs. LP: 24.8 ± 6.3 ohm), and the time to minimum LI was significantly shorter (HP: 15.0 ± 6.3 vs. LP: 19.3 ± 6.6 s) in the HP setting. The unipolar electrogram analysis of three patients revealed that the electrogram indicating transmural lesion formation was observed more frequently in the HP setting.<br /><b>Conclusion</b><br />In LI-guided ablation, the HP could achieve a larger LI drop and shorter time to minimum LI, which may result in more transmural lesion formation compared to a LP setting.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 02 Aug 2023; epub ahead of print</small></div>

<div><h4>Adjunct posterior wall isolation reduces the recurrence of atrial fibrillation in patients undergoing cryoballoon ablation: A systematic review and meta-analysis.</h4><i>Mumtaz M, Jabeen S, Danial A, Chaychi MTM, ... Mumtaz T, Herweg B</i><br /><b>Background</b><br />Recurrence rates of atrial fibrillation (AF) remain high even after complete wide area circumferential pulmonary vein isolation (PVI). In recent years adjunct posterior wall isolation (PWI) has been performed in patients with more persistent forms of AF but the benefits remain unclear.<br /><b>Aim</b><br />The objective of this meta-analysis was to evaluate the efficacy of adjunct posterior wall isolation in reducing recurrence rates of AF using cryoballoon ablation (CBA).<br /><b>Methods</b><br />We searched PubMed, Google Scholar, Clinicaltrials.gov and Cochrane CENTRAL. We included studies comparing PVI to PVI + PWI in patients with either persistent or paroxysmal AF (PAF) undergoing CBA. After data extraction and quality assessment of the studies, we assessed recurrence rates of atrial tachy-arrhythmias (AF, atrial flutter, and atrial tachycardia) as well as total ablation time and procedural adverse events. Risk ratio (RR), mean difference (MD), and 95% confidence interval (CI) were calculated using Review Manager.<br /><b>Results</b><br />Concomitant PWI exhibited a substantial reduction in the risk of AF recurrence (RR: 0.51; 95% CI: 0.42-0.63, p < .00001), as well as all atrial arrhythmias (RR: 0.58; 95% CI: 0.49-0.68, p < .00001). On subgroup analysis, in patients with only PAF, adjunct PWI resulted in significant reduction in recurrence risk of AF (RR: 0.56; 95% CI: 0.41-0.76, p = .0002) as well. There was no significant difference in adverse events between both groups (RR: 0.90; 95% CI: 0.44-1.86; p = .78), whereas total ablation time was significantly increased in PVI + PWI group (MD: 21.75; 95% CI: 11.13-32.37, p < .0001).<br /><b>Conclusion</b><br />Adjunct PWI when compared to PVI alone decreases recurrence rates of atrial fibrillation after CBA of patients with persistent as well as paroxysmal atrial fibrillation.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 01 Aug 2023; epub ahead of print</small></div>

<div><h4>Noninvasive ECG imaging of the intrinsic atrial pacemaker and atrial activation in surgically repaired or palliated congenital heart disease.</h4><i>Moore BM, Al-Kaisy A, Joshi SB, Lui E, Grigg LE, Kalman JM</i><br /><b>Introduction</b><br />Sinus node location, function, and atrial activation are often abnormal in patients with congenital heart disease (CHD), due to anatomical, surgical, and acquired factors. We aimed to perform noninvasive electrocardiographic imaging (ECGI) of the intrinsic atrial pacemaker and atrial activation in patients with surgically repaired or palliated CHD, compared with control patients with structurally normal hearts.<br /><b>Methods and results</b><br />Atrial ECGI was performed in eight CHD patients with prespecified diagnoses (Fontan circulation, dextro transposition of the great arteries post Mustard/Senning, tetralogy of Fallot), and three controls. Activation and propagation maps were constructed in presenting rhythm. Wavefront propagation was analyzed to identify (1) intrinsic atrial pacemaker breakout site, (2) morphological right atrial (RA) activation pattern, (3) morphological left atrial (LA) breakout sites (i.e., interatrial connections), (4) LA activation pattern, and (5) putative lines of block. Physiologically appropriate atrial activation and propagation maps were able to be constructed. In the majority of patients, atrial breakouts were in keeping with the sinus node, observed in a crescent-shaped distribution from the anterior superior vena cava to the posterior RA. Ectopic atrial pacemaker sites were demonstrated in the atriopulmonary (AP) Fontan patient (very diffuse posterolateral RA) and Mustard patient (very posterior RA competing with a low RA focus). RA propagation was laminar in controls, but suggested either a line of block or conduction slowing consistent with an atriotomy scar in the tetralogy of Fallot (TOF) patients. Putative lines of block were more complex and RA propagation more abnormal in the atrial switch and AP Fontan patients, compared with the TOF patients. RA activation in the extracardiac Fontan patients was relatively laminar. Earliest LA breakout was most commonly observed in the region of Bachmann\'s Bundle in both controls and CHD patients, except for posterior LA breakouts in two patients. LA activation was typically more homogeneous than RA activation in CHD patients.<br /><b>Conclusion</b><br />ECGI can be utilized to create a noninvasive mapping model of atrial activation in postsurgical CHD, demonstrating atrial pacemaker location, putative lines of block and interatrial connections. Once validated invasively, this may have clinical implications in predicting risk of sinus node dysfunction and atrial arrhythmias, or in guiding catheter ablation.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 01 Aug 2023; epub ahead of print</small></div>

<div><h4>Fast-slow atrioventricular nodal re-entrant tachycardia incorporating superior and inferolateral left atrial slow pathways.</h4><i>Matsumoto K, Mori H, Nagashima K, Kaneko Y, Kato R</i><br /><b>Background</b><br />A 70-year-old man revealed a rare type of atrioventricular nodal re-entrant tachycardia (AVNRT) involving distinct retrograde pathways, superior slow pathway, and inferolateral left atrial slow pathway.<br /><b>Result</b><br />Radiofrequency ablation was successfully performed on the noncoronary cusp and in the left atrium, respectively, to eliminate the tachycardias.<br /><b>Discussion and conclusion</b><br />Due to the anomalous electrical conduction patterns, careful diagnosis and ablation strategies were necessary to avoid the risk of atrioventricular block. These findings underscore the diversity and complexity of AVNRT and highlight the importance of tailored therapeutic approaches.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 01 Aug 2023; epub ahead of print</small></div>

<div><h4>A comparative study of the two leadless pacemakers in clinical practice.</h4><i>Shantha G, Brock J, Singleton MJ, Schmitt AJ, ... Whalen P, Bhave P</i><br /><b>Introduction</b><br />AVEIR-VR leadless pacemaker (LP) was recently approved for clinical use. Although trial data were promising, post-approval real world data with regard to its effectiveness and safety is lacking. To report our early experience with AVEIR-VR LP with regard to its effectiveness and safety and compare it with MICRA-VR.<br /><b>Methods</b><br />The first 25 patients to undergo AVEIR-VR implant at our institution between June and November 2022, were compared to 25 age- and sex-matched patients who received MICRA-VR implants.<br /><b>Results</b><br />In both groups, mean age was 73 years and 48% were women. LP implant was successful in 100% of patients in both groups. Single attempt deployment was achieved in 80% of AVEIR-VR and 60% of MICRA-VR recipients (p = 0.07). Fluoroscopy, implant, and procedure times were numerically longer in the AVEIR-VR group compared to MICRA-VR group (p > 0.05). No significant periprocedural complications were noted in both groups. Incidence of ventricular arrhythmias were higher in the AVEIR-VR group (20%) compared to the MICRA-VR group (0%) (p = 0.043). At 2 and 8 weeks follow-up, device parameters remained stable in both groups with no device dislodgements. The estimated battery life at 8 weeks was significantly longer in the AVEIR-VR group (15 years) compared to the MICRA-VR group (8 years) (p = 0.047). With 3-4 AVEIR-VR implants, the learning curve for successful implantation reached a steady state.<br /><b>Conclusion</b><br />Our initial experience with AVEIR-VR show that it has comparable effectiveness and safety to MICRA-VR. Larger sample studies are needed to confirm our findings.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 31 Jul 2023; epub ahead of print</small></div>

<div><h4>Cardiac resynchronization therapy in patients with a prior history of atrial fibrillation: Insights from four major clinical trials.</h4><i>Dalgaard F, Fudim M, Al-Khatib SM, Friedman DJ, ... Inoue LYT, Sanders GD</i><br /><b>Aims</b><br />To investigate the association of cardiac resynchronization therapy (CRT) on outcomes among participants with and without a history of atrial fibrillation (AF).<br /><b>Methods</b><br />Individual-patient-data from four randomized trials investigating CRT-Defibrillators (COMPANION, MADIT-CRT, REVERSE) or CRT-Pacemakers (COMPANION, MIRACLE) were analyzed. Outcomes were time to a composite of heart failure hospitalization or all-cause mortality or to all-cause mortality alone. The association of CRT on outcomes for patients with and without a history of AF was assessed using a Bayesian-Weibull survival regression model adjusting for baseline characteristics.<br /><b>Results</b><br />Of 3964 patients included, 586 (14.8%) had a history of AF; 2245 (66%) were randomized to CRT. Overall, CRT reduced the risk of the primary composite endpoint (hazard ratio [HR]: 0.69, 95% credible interval [CI]: 0.56-0.81). The effect was similar (posterior probability of no interaction = 0.26) in patients with (HR: 0.78, 95% CI: 0.55-1.10) and without a history of AF (HR: 0.67, 95% CI: 0.55-0.80). In these four trials, CRT did not reduce mortality overall (HR: 0.82, 95% CI: 0.66-1.01) without evidence of interaction (posterior probability of no interaction = 0.14) for patients with (HR: 1.09, 95% CI: 0.70-1.74) or without a history of AF (HR: 0.70, 95% CI: 0.60-0.97).<br /><b>Conclusion</b><br />The association of CRT on the composite endpoint or mortality was not statistically different for patients with or without a history of AF, but this could reflect inadequate power. Our results call for trials to confirm the benefit of CRT recipients with a history of AF.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 31 Jul 2023; epub ahead of print</small></div>

<div><h4>Impact of obesity on catheter ablation of atrial fibrillation: Patient characteristics, procedural complications, outcomes, and quality of life.</h4><i>Tabaja C, Younis A, Santageli P, Farwati M, ... Wazni OM, Hussein AA</i><br /><b>Introduction</b><br />Obesity is a well-known risk factor for atrial fibrillation (AF). We aim to evaluate the effect of baseline obesity on procedural complications, AF recurrence, and symptoms following catheter ablation (CA).<br /><b>Methods</b><br />All consecutive patients undergoing AF ablation (2013-2021) at our center were enrolled in a prospective registry. The study included all consecutive patients with available data on body mass index (BMI). Primary endpoint was AF recurrence based on electrocardiographic documentation. Patients were categorized into five groups according to their baseline BMI. Patients survey at baseline and at follow-up were used to calculate AF symptom severity score (AFSS) as well as AF burden (mean of AF duration score and AF frequency score; scale 0: no AF to 10: continuous and 9 frequencies/durations in between). Patients were scheduled for follow-up visits with 12-lead electrocardiogram at 3, 6, and 12 months after ablation, and every 6 months thereafter.<br /><b>Results</b><br />A total of 5841 patients were included (17% normal weight, 34% overweight, 27% Class I, 13% Class II, and 9% Class III obesity). Major procedural complications were low (1.5%) among all BMI subgroups. At 3 years AF recurrence was the highest in Class III obesity patients (48%) followed by Class II (43%), whereas Class I, normal, and overweight had similar results with lower recurrence (35%). In multivariable analyses, Class III obesity (BMI ≥ 40) was independently associated with increased risk for AF recurrence (hazard ratio, 1.30; confidence interval, 1.06-1.60; p = .01), whereas other groups had similar risk in comparison to normal weight. Baseline AFSS was lowest in normal weight, and highest in Obesity-III, median (interquartile range) 10 (5-16) versus 15 (10-21). In all groups, CA resulted in a significant improvement in their AFSS with a similar magnitude among the groups. At follow-up, AF burden was minimal and did not differ significantly between the groups.<br /><b>Conclusion</b><br />AF ablation is safe with a low complication rate across all BMI groups. Morbid obesity (BMI ≥ 40) was significantly associated with reduced AF ablation success. However, ablation resulted in improvement in QoL including reduction of the AFSS, and AF burden regardless of BMI.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 26 Jul 2023; epub ahead of print</small></div>

<div><h4>\"Function follows form\": Role of cardiac magnetic resonance for ventricular arrhythmia risk stratification in patients with cardiac sarcoidosis.</h4><i>Magnocavallo M, Vetta G, Polselli M, Cauti FM, ... Bianchi S, Della Rocca DG</i><br /><b>Introduction</b><br />Cardiac involvement is common and may become clinically relevant in approximately 5%-10% of patients with systemic sarcoidosis. Although reduced left ventricular ejection fraction is a recognized predictor of mortality, recent studies have suggested an increased risk of ventricular arrhythmia (VAs) and sudden cardiac death (SCD) in patients with cardiac sarcoidosis (CS) and evidence of late gadolinium enhancement-cardiac magnetic resonance (LGE-CMR), irrespective of the underlying left ventricular systolic function. We performed a meta-analysis to assess the correlation between VAs/SCD and presence of LGE-CMR in CS patients.<br /><b>Methods</b><br />We systematically searched Medline, Embase, and Cochrane electronic databases up to January 2, 2023, for studies enrolling patients with suspected or confirmed CS undergoing LGE-CMR. Clinical outcomes of interest included clinically relevant VAs, defined as sustained ventricular tachycardia, ventricular fibrillation, SCD, or aborted SCD during follow-up. The effect size was estimated using a random-effect model as risk ratio (RR) and relative 95% confidence interval (CI).<br /><b>Results</b><br />A total of 14 studies fulfilled the selection criteria and were included in the final analysis. Among 1273 patients, LGE was detected in 465 (36.5%; Group LGE+). Males accounted for 45.2% (95% CI: 40.5%-55.7%) of the total population and the average age was 56.8 (95% CI: 52.7%-60.9) years. A total of 104 (22.3%) of 465 LGE+ patients experienced a clinically relevant VA, compared to 6 (0.7%) of 808 LGE- ones. LGE+ was associated with a ninefold increased risk in life-threatening VAs (22.3% vs. 0.7%; RR = 9.52; 95% CI [5.18-17.49]; p < .0001) compared to patients without LGE (heterogeneity I<sup>2</sup>  = 0%).<br /><b>Conclusion</b><br />In our meta-analysis, LGE+ in patients with CS was associated with a ninefold increased risk in life-threatening VAs compared to patients without LGE.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 26 Jul 2023; epub ahead of print</small></div>

<div><h4>Laser lead extraction in octo- and nonagenarians. A subgroup analysis from the GALLERY registry.</h4><i>Pecha S, Chung DU, Burger H, Osswald B, ... Hakmi S, GALLERY investigators</i><br /><b>Introduction</b><br />In an aging population with cardiac implantable electronic devices, an increasing number of octo- and even nonagenarians present for lead extraction procedures. Those patients are considered at increased risk for surgical procedures including lead extraction. Here, we investigated safety and efficacy of transvenous lead extraction in a large patient cohort of octo- and nonagenarians.<br /><b>Methods and results</b><br />A subgroup analysis of all patients aged ≥80 years (n = 499) in the German Laser Lead Extraction Registry (GALLERY) was performed. Outcomes were compared to the nonoctogenarians from the registry. Primary extraction method was Laser lead extraction, with additional use of mechanical rotational sheaths or femoral snares, if necessary. An analysis of patient- and device characteristics, as well as an assessment of predictors for adverse events via multivariate analyses was conducted. Mean patients age was 84.3 ± 3.7 years in the octogenarians group and 64.1 ± 12.4 years in the nonoctogenarians group. The median lead dwell time was 118.0 months (78; 167) and 92.0 months [60; 133], p < .001 in the octogenarians and nonoctogenarians group, respectively. Clinical procedural success rate was achieved in 97.6% of the cases in octogenarians and 97.9% in nonoctogenarians (p = .70). Overall complication rate was 4.4% in octogenarians and 4.3% in nonoctogenarians (0.91). In octogenarians procedure-related mortality was 0.8% and all-cause in-hospital mortality was 5.4%, while in nonoctogenarians, procedure related and all-cause in-hospital mortality were 0.5% and 3.1%, respectively. A body mass index (BMI) <20 kg/m<sup>2</sup> , was the only statistically significant predictor for procedure-related complications in octogenarians, while systemic infection, BMI ≤20 kg/m<sup>2</sup> , procedural complications and chronic kidney disease were predictors for in-hospital mortality.<br /><b>Conclusions</b><br />Laser lead extraction in octo- and nonagenarians is safe and effective. BMI ≤20 kg/m<sup>2</sup> was the only statistically significant predictor for procedural complications. According to our data, advanced age should not be considered as contraindication for laser lead extraction.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 26 Jul 2023; epub ahead of print</small></div>

<div><h4>Direct current cardioversion practices following percutaneous left atrial appendage closure.</h4><i>Bhuta S, Shaaban A, Binda NC, Antaki J, ... Daoud EG, Hummel JD</i><br /><b>Introduction</b><br />Among patients with non-valvular atrial fibrillation (AF) and percutaneous left atrial appendage closure (LAAC) undergoing direct current cardioversion (DCCV), the need for and use of LAA imaging and oral anticoagulation (OAC) is unclear.<br /><b>Objective</b><br />The purpose of this study is to evaluate the real-world use of transesophageal echocardiography (TEE) or cardiac computed tomography angiography (CCTA) before DCCV and use of OAC pre- and post-DCCV in patients with AF status post percutaneous LAAC.<br /><b>Methods</b><br />This retrospective single center study included all patients who underwent DCCV after percutaneous LAAC from 2016 to 2022. Key measures were completion of TEE or CCTA pre-DCCV, OAC use pre- and post-DCCV, incidence of left atrial thrombus (LAT) or device-related thrombus (DRT), incidence of peri-device leak (PDL), and DCCV-related complications (stroke, systemic embolism, device embolization, major bleeding, or death) within 30 days.<br /><b>Results</b><br />A total of 76 patients with AF and LAAC underwent 122 cases of DCCV. LAAC consisted of 47 (62%), 28 (37%), and 1 (1%) case of Watchman 2.5, Watchman FLX, and Lariat, respectively. Among the 122 DCCV cases, 31 (25%) cases were identified as \"non-guideline based\" due to: (1) no OAC for 3 weeks and no LAA imaging within 48 h before DCCV in 12 (10%) cases, (2) no OAC for 4 weeks following DCCV in 16 (13%) cases, or (3) both in 3 (2%) cases. Among the 70 (57%) cases that underwent TEE or CCTA before DCCV, 16 (23%) cases had a PDL with a mean size of 3.0 ± 1.1 mm, and 4 (6%) cases had a LAT/DRT on TEE resulting in cancellation. There were no DCCV-related complications within 30 days.<br /><b>Discussion</b><br />There is a widely varied practice pattern of TEE, CCTA, and OAC use with DCCV after LAAC, with a 6% rate of LAT/DRT. LAA imaging before DCCV appears prudent in all cases, especially within 1 year of LAAC, to assess for device position, PDL, and LAT/DRT.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 26 Jul 2023; epub ahead of print</small></div>

<div><h4>Optimization of superior vena cava isolation with aid of ablation index guidance.</h4><i>Liu J, Guan W, Guo J, Li X, ... Niu G, Yao Y</i><br /><b>Introduction</b><br />To investigate the optimal range of quantitative ablation index (AI) value during superior vena cava (SVC) electrical isolation by radiofrequency catheter ablation (RFCA).<br /><b>Methods</b><br />First, in a development cohort of patients with atrial fibrillation (AF), the RFCA with 40 W was performed to complete SVC isolation guided by the conduction breakthrough point from the right atrium to SVC. Then, the range of AI value was calculated by offline analysis on different segments of SVC. Lastly, for the validation of AF patients, the safety and effectiveness of SVC isolation with the optimized target range of AI value were evaluated with an additional adenosine test.<br /><b>Results</b><br />A total of 101 patients with AF were included in the study (44 patients in the development cohort/57 in the validation cohort). The segmental ablation strategy was applied in 70% of the patients. According to the offline analysis of the AI values in the development cohort, the target AI value range was set as 350-400. The success rate of SVC isolation in the validation cohort was significantly higher than that in the exploration cohort (100% vs. 90.9%, p = .02), and no complications occurred in the exploration cohort. During the adenosine test, the recovery rate of electrical conduction in SVC was significantly lower than that in the pulmonary vein (3.5% vs. 17.5%).<br /><b>Conclusion</b><br />The target AI value with a range from 350 to 400 is safe and effective for high-power RFCA to complete SVC isolation.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 26 Jul 2023; epub ahead of print</small></div>

<div><h4>Atrial mechanical contraction and ambulatory atrioventricular synchrony: Predictors from the OPTIVALL study.</h4><i>Briongos-Figuero S, Estévez Paniagua Á, Sánchez Hernández A, Jiménez Loeches S, ... Vaqueriza Cubillo D, Muñoz-Aguilera R</i><br /><b>Introduction</b><br />The role that preprocedural factors have on atrioventricular synchrony (AVS) provided by leadless pacemakers requires investigation.<br /><b>Methods and results</b><br />We aimed to assess the correlation between mitral inflow echocardiographic parameters and p-wave morphology with the accelerometer A4 signal amplitude. We also sought to identify clinical and echocardiographic predictors of optimal ambulatory AVS (≥85% of cardiac cycles). Forty-three patients undergoing Micra AV implant from June 2020 to March 2023 were prospectively enrolled. Baseline echocardiogram and 12-lead resting ECG were performed. Device follow-up was scheduled at 24 h, 1, 3, and 6 months and yearly after the implant. Ambulatory AVS was studied with a 24 h Holter monitor performed at 3 months follow-up in 35 patients who remained in VDD mode. A4 signal amplitude at 1 month correlated to peak A wave velocity (r = .376; p = .024) at echocardiogram, but no relationship was found with peak A\' wave velocity, E/A, or E\'/A\' ratio. P-wave amplitude in lead I and aVF correlated to A4 signal amplitude at 1- and 3-months follow-up, respectively. Median AVS during 24 h of daily activities was 85.6 ± 7.6% and remained stable up to 100 bpm. Twenty-three out of 35 patients (65.7%) reached optimal ambulatory AVS. There was no association between mitral inflow echocardiographic parameters and optimal AVS. Diabetes (OR: 0.05, 95% CI: 0.01-0.47; p = .009) and chronic obstructive pulmonary disease (COPD) (OR: 0.06, 95% CI: 0.01-0.63; p = .019) strongly predicted ambulatory AVS <85%.<br /><b>Conclusions</b><br />Diabetes and COPD should be considered when selecting candidates for Micra AV. Measurements of pulsed wave Doppler mitral inflow do not systematically reflect the behavior of the A4 signal amplitude.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 22 Jul 2023; epub ahead of print</small></div>

<div><h4>Utility of short-time electrocardiogram to assess risk for atrial arrhythmia recurrence: Impact of atrial premature beat occurrence 1 day after pulmonary vein isolation for atrial fibrillation.</h4><i>Yamada S, Kaneshiro T, Nodera M, Amami K, ... Yamadera Y, Takeishi Y</i><br /><b>Introduction</b><br />Atrial premature beats (APBs) are the trigger for atrial fibrillation (AF). We sought to investigate the clinical significance of APB occurrence 1 day after pulmonary vein isolation (PVI) for AF using a short-time electrocardiogram.<br /><b>Methods</b><br />A total of 206 patients undergoing PVI for paroxysmal AF were included. Electrocardiogram recording for 100 consecutive beats was performed 1 day after PVI. The patients were divided into two groups: those with reproducible APBs (≥1 beat) during reassessment (APB group, n = 49) or those without (non-APB group, n = 157). Late recurrence was defined as atrial tachyarrhythmia recurrence 3-12 months after PVI. The impact of APB occurrence on outcomes was investigated.<br /><b>Results</b><br />Late recurrence occurred in 19 patients (9.2%). The presence of low-voltage areas, left atrial volume, and recurrence rate were higher in the APB group than in the non-APB group. In the APB group, the patients with recurrence had lower prematurity index (PI, coupling interval of APB/previous cycle length) compared to those without. Receiver-operating characteristic analysis revealed PI (<59.3) to be a predictive factor of recurrence (area under the curve: 0.733). The study subjects were then reclassified into three groups according to the absence of APB occurrence (n = 157), presence thereof with PI ≥ 59.3 (n = 33), and presence with PI < 59.3 (n = 16). The multivariate Cox models revealed that APB with PI < 59.3 was an independent predictor for recurrence (hazard ratio, 8.735; p < 0.001).<br /><b>Conclusion</b><br />A short-time electrocardiogram enables risk assessment for arrhythmia recurrence, and APB with low PI 1 day after PVI is a powerful predictor.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 22 Jul 2023; epub ahead of print</small></div>

<div><h4>Acute lesion extension following pulmonary vein isolation with two novel single shot devices: Pulsed field ablation versus multielectrode radiofrequency balloon.</h4><i>My I, Lemoine MD, Butt M, Mencke C, ... Rillig A, Metzner A</i><br /><b>Introduction</b><br />Pulsed-field ablation (PFA) and the multielectrode radiofrequency balloon (RFB) are two novel ablation technologies to perform pulmonary vein isolation (PVI). It is currently unknown whether these technologies differ in lesion formation and lesion extent. We compared the acute lesion extent after PVI induced by PFA and RFB by measuring low-voltage area in high-density maps and the release of biomolecules reflecting cardiac injury.<br /><b>Methods</b><br />PVI was performed with a pentaspline catheter (FARAPULSE) applying PFA or with the compliant multielectrode RFB (HELIOSTAR). Before and after PVI high-density mapping with CARTO 3 was performed. In addition, blood samples were taken before transseptal puncture and after post-PVI remapping and serum concentrations of high-sensitive Troponin I were quantified by immunoassay.<br /><b>Results</b><br />Sixty patients undergoing PVI by PFA (n = 28, age 69 ± 12 year, 60% males, 39.3% persistent atrial fibrillation [AF]) or RFB (n = 32, age 65 ± 13 year, 53% males, 21.9% persistent AF) were evaluated. Acute PVI was achieved in all patients in both groups. Mean number of PFA pulses was 34.2 ± 4.5 and mean number RFB applications was 8.5 ± 3 per patient. Total posterior ablation area was significantly larger in PFA (20.7 ± 7.7 cm²) than in RFB (7.1 ± 2.09 cm²; p < .001). Accordingly, posterior ablation area for each PV resulted in larger lesions after PFA versus RFB (LSPV 5.2 ± 2.7 vs. 1.9 ± 0.8 cm², LIPV 5.5 ± 2.3 vs. 1.9 ± 0.8 cm², RSPV 4.7 ± 1.9 vs. 1.6 ± 0.5 cm², RIPV 5.3 ± 2.1 vs. 1.6 ± 0.7 cm,² respectively; p < .001). In a subset of 38 patients, increase of hsTropI was higher after PFA (625 ± 138 pg/mL, n = 28) versus RFB (148 ± 36 pg/mL, n = 10; p = .049) supporting the evidence of larger lesion extent by PFA.<br /><b>Conclusion</b><br />PFA delivers larger acute lesion areas and higher troponin release upon successful PVI than multielectrode RFB-based PVI in this single-center series.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 20 Jul 2023; epub ahead of print</small></div>

<div><h4>Trans-2,3-enoyl-CoA reductase-like-related catecholaminergic polymorphic ventricular tachycardia with regular ventricular tachycardia and response to flecainide.</h4><i>Ebrahim MA, Alkhabbaz AA, Albash B, AlSayegh AH, Webster G</i><br /><b>Introduction</b><br />We describe a unique case of TECRL-CPVT presented with cardiac arrest.<br /><b>Methods</b><br />Post resuscitation, the patient developed regular ventricular tachycardia featuring a left purkinje system morphology.<br /><b>Results</b><br />There was clear suppression of arrhythmia with the addition of flecainide and isolated ventricular ectopy causing secondary T-wave changes.<br /><b>Conclusion</b><br />A high index of suspicion was required to eventually make the diagnosis through whole exome sequencing.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 20 Jul 2023; epub ahead of print</small></div>

<div><h4>Linear epicardial cryoablation effects in a porcine model: Lesion characteristics and vascular risk.</h4><i>Hayase J, Fishbein G, Rerkpichaisuth V, Chung WH, ... Shivkumar K, Bradfield JS</i><br /><b>Introduction</b><br />Cryoablation in open-chest surgical interventions for ventricular arrhythmias has been reported with reasonable procedural outcomes. However, the characteristics of cryoablation lesions on the ventricular myocardium are not well defined. The purpose of the present study was to determine the tissue and vascular effects of a linear epicardial cryoablation probe in a porcine animal model.<br /><b>Methods</b><br />Five adult Yorkshire swine underwent median sternotomy and application of linear cryoablation lesions using a malleable aluminum linear cryoablation probe of varying duration (2, 3, 4, and 5 min), including one lesion placed intentionally over the left anterior descending coronary (LAD) artery. Histological analysis was performed.<br /><b>Results</b><br />Maximum lesion depth was approximately 1.0 cm with 3 min freezes, with no significant increase in depth achieved with longer lesions. No transmural lesions were achieved. No large vessel epicardial coronary artery injuries were seen to the LAD; however, surprisingly, remote isolated interventricular septal injury was seen in all animals, suggestive of possible compromise of smaller coronary arterial vessels.<br /><b>Conclusion</b><br />Single application freezes with an aluminum linear cryoablation probe can create homogeneous ablative lesions over the ventricular myocardium with a maximum depth of approximately 1.0 cm. No large vessel injury occurred with direct lesion application of the LAD; however, small coronary vessels may be at risk.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 20 Jul 2023; epub ahead of print</small></div>

<div><h4>Preclinical evaluation of a novel single-shot pulsed field ablation system for pulmonary vein and atrial ablation.</h4><i>Aryana A, Ji SY, Hata C, de la Rama A, Nguyen K, Panescu D</i><br /><b>Introduction</b><br />Pulsed field ablation (PFA) is a nonthermal ablative strategy that achieves cell death via electroporation. Herein, we investigated the preclinical safety and efficacy of PFA using two novel 8-French, 16-electrode spiral PFA/mapping catheters (ElePulse; CRC EP, Inc.).<br /><b>Methods</b><br />Bipolar PFA (>1.8 kV) was performed using 30 s, single-shot, QRS-gated applications. Altogether, 94 atrial structures were ablated in 23 swine, one canine, and one ovine, including right and left atria and atrial appendages, pulmonary veins, and superior and inferior (IVC) vena cavae. We also examined the impact of PFA on the phrenic nerve (14 swine) and on a deviated esophagus after delivery of PFA from inside the IVC (five swine).<br /><b>Results</b><br />All applications were single-shot without catheter repositioning. Minimal microbubbling was observed without significant skeletal muscle twitching/activation (mean acceleration: 0.05 m/s<sup>2</sup> ). There was a marked reduction in post-PFA versus pre-PFA atrial electrogram amplitude (0.17 ± 0.21 vs. 1.18 ± 1.08 mV; p < .0001). Lesion durability was demonstrated up to 3 months in all targeted tissues. Histologically, lesions were contiguous and transmural, except in the atrial appendage, and without any thermal effects. Magnetic resonance, gross, and histologic examinations of the brain, rete mirabile, and kidneys revealed no thromboembolism. No acute/long-term phrenic nerve dysfunction was encountered. Although within 2 h of ablation, histologic examinations of the esophagus revealed acute PFA-related changes in the muscular layer, these completely resolved by 21 ± 5 days.<br /><b>Conclusion</b><br />A novel, single-shot, spiral PFA system is capable of safely creating large, durable atrial lesions without significant adverse effects on the phrenic nerve or the esophagus.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 18 Jul 2023; epub ahead of print</small></div>

<div><h4>Effect of sodium glucose cotransporter 2 inhibitors on atrial tachy-arrhythmia burden in patients with cardiac implantable electronic devices.</h4><i>Younis A, Arous T, Klempfner R, Kharsa A, ... Aktas M, Goldenberg I</i><br /><b>Introduction</b><br />Use of sodium glucose cotransporter 2 inhibitors (SGLT2i) was associated with a reduction in atrial fibrillation hospitalizations. Therefore, we aim to evaluate the effects of SGLT2i on atrial tachy-arrhythmias (ATA) in patients with cardiac implantable electronic devices (CIEDs).<br /><b>Methods</b><br />All 13 888 consecutive patients implanted with a CIED in two tertiary medical centers were enrolled. Treatment with SGLT2i was assessed as a time dependent variable. The primary endpoint was the total number of ATA. Secondary endpoints included total number of ventricular tachy-arrhythmias (VTA), ATA and VTA, and death. All events were independently adjudicated blinded to the treatment. Multivariable propensity score modeling was performed.<br /><b>Results</b><br />During a total follow-up of 24 442 patient years there were 62 725 ATA and 10 324 VTA events. Use of SGLT2i (N = 696) was independently associated with a significant 22% reduction in the risk of ATA (hazard ratio [HR] = 0.78 [95% confidence interval {CI} = 0.70-0.87]; p < .001); 22% reduction in the risk of ATA/VTA (HR = 0.78 [95% CI = 0.71-0.85]; p < .001); and with a 35% reduction in the risk of all-cause mortality (HR = 0.65 [95% CI = 0.45-0.92]; p = .015), but was not significantly associated with VTA risk (HR = 0.92 [95% CI = 0.80-1.06]; p = .26). SGLT2i were associated with a lower ATA burden in heart failure (HF) patients but not among diabetes patients (HF: HR = 0.68, 95% CI = 0.58-0.80, p < .001 vs. Diabetes: HR = 0.95, 95% CI = 0.86-1.05, p = .29; p < .001 for interaction between SGLT2i indication and ATA burden).<br /><b>Conclusion</b><br />Our real world findings suggest that in CIED HF patients, those with SGLT2i had a pronounced reduction in ATA burden and all-cause mortality when compared with those not on SGLT2i.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 15 Jul 2023; epub ahead of print</small></div>

<div><h4>Novel algorithms improve arrhythmia detection accuracy in insertable cardiac monitors.</h4><i>Gopinathannair R, Shehata MM, Afzal MR, Manyam H, ... Katcher MS, Lakkireddy D</i><br /><b>Introduction</b><br />Insertable cardiac monitors (ICMs) are commonly used to diagnose cardiac arrhythmias. False detections in the latest ICM systems remain an issue, primarily due to inaccurate R-wave sensing. New discrimination algorithms were developed and tested to reduce false detections of atrial fibrillation (AF), pause, and tachycardia episodes in ICMs.<br /><b>Methods</b><br />Stored electrograms (EGMs) of AF, pause, and tachycardia episodes detected by Abbott Confirm Rx™ ICMs were extracted from the Merlin.net™ Patient Care Network, and manually adjudicated to establish independent training and testing datasets. New discrimination algorithms were developed to reject false episodes due to inaccurate R-wave sensing, P-wave identification, and R-R interval patterns. The performance of these new algorithms was quantified by false positive reduction (FPR) and true positive maintenance (TPM), relative to the existing algorithms.<br /><b>Results</b><br />The new AF detection algorithm was trained on 5911 EGMs from 744 devices, resulting in 66.9% FPR and 97.8% TPM. In the testing data set of 1354 EGMs from 119 devices, this algorithm achieved 45.8% FPR and 97.0% TPM. The new pause algorithm was trained on 7178 EGMs from 1490 devices, resulting in 70.9% FPR and 98.7% TPM. In the testing data set of 1442 EGMs from 340 devices, this algorithm achieved 74.4% FPR and 99.3% TPM. The new tachycardia algorithm was trained on 520 EGMs from 204 devices, resulting in 57.0% FPR and 96.6% TPM. In the testing data set of 459 EGMs from 237 devices, this algorithm achieved 57.9% FPR and 96.5% TPM.<br /><b>Conclusion</b><br />The new algorithms substantially reduced false AF, pause, and tachycardia episodes while maintaining the majority of true arrhythmia episodes detected by the Abbott ICM algorithms that exist today. Implementing these algorithms in the next-generation ICM systems may lead to improved detection accuracy, in-clinic efficiency, and device battery longevity.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 14 Jul 2023; epub ahead of print</small></div>

<div><h4>Retroflexed catheter course reduces the risk of right free wall accessory pathway recurrence.</h4><i>Przybylski R, DeWitt ES, Meziab O, Gauvreau K, ... Walsh EP, Mah DY</i><br /><b>Introduction</b><br />Accessory atrioventricular pathways (APs) may mediate atrioventricular reciprocating tachycardia and, in some cases, have the potential to conduct atrial tachycardia rapidly, which can be life threatening. While catheter ablation can be curative, ablation of right free wall APs is associated with a high rate of recurrence, likely secondary to reduced catheter stability along the right free wall atrioventricular groove. We sought to identify characteristics associated with a lower rate of recurrence and hypothesized ablation lesions placed on the ventricular side of the atrioventricular groove using a retroflexed catheter approach would decrease rates of recurrence.<br /><b>Methods and results</b><br />Retrospective chart review of patients who underwent catheter ablation of a right free wall AP from January 1, 2008 through June 1, 2021 with >2 months follow up. Cox proportional hazards regression was used to identify relationships between predictor variables and AP recurrence. We identified 95 patients who underwent ablation of 98 right free wall APs. Median age was 13.1 years and median weight at ablation was 52.3 kg. Overall, 23/98 (23%) APs recurred. Use of a retroflexed catheter course approaching the atrioventricular groove from the ventricular aspect was associated with reduced risk of AP recurrence with (univariable hazard ratio of 0.10 [95% confidence interval: 0.01-0.78]), which remained significant in multiple two variable Cox proportional hazards models.<br /><b>Conclusion</b><br />Use of a retroflexed catheter course is associated with a reduced likelihood of AP recurrence. This approach results in improved catheter stability and should be considered for ablation of right free wall APs.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 14 Jul 2023; epub ahead of print</small></div>

<div><h4>Preferred left ventricular lead position for upgrade from right ventricular pacing to cardiac resynchronization therapy.</h4><i>Ogano M, Iwasaki YK, Okada T, Tanabe J, Shimizu W, Asai K</i><br /><b>Introduction</b><br />Cardiac resynchronization therapy (CRT) is well-established for treating symptomatic heart failure with electrical dyssynchrony. The left ventricular (LV) lead position is recommended at LV posterolateral to lateral sites in patients with left bundle branch block; however, its preferred region remains unclear in patients being upgraded from right ventricular (RV) apical pacing to CRT. This study aimed to identify the preferred LV lead position for upgrading conventional RV apical pacing to CRT.<br /><b>Methods</b><br />We used electrode catheters positioned at the RV apex and LV anterolateral and posterolateral sites via the coronary sinus (CS) branches to measure the ratio of activation time to QRS duration from the RV apex to the LV anterolateral and posterolateral sites during RV apical pacing. Simultaneous biventricular pacing was performed at the RV apex and each LV site, and the differences in QRS duration and LV dP/dt<sub>max</sub> from those of RV apical pacing were measured.<br /><b>Results</b><br />Thirty-seven patients with anterolateral and posterolateral LV CS branches were included. During RV apical pacing, the average ratio of activation time to QRS duration was higher at the LV anterolateral site than at the LV posterolateral site (0.90 ± 0.06 vs. 0.71 ± 0.11, p < .001). The decreasing ratio of QRS duration and the increasing ratio of LV dP/dt<sub>max</sub> were higher at the LV anterolateral site than at the posterolateral site (45.7 ± 18.0% vs. 32.0 ± 17.6%, p < .001; 12.7 ± 2.9% vs. 3.7 ± 8.2%, p < .001, respectively) during biventricular pacing compared with RV apical pacing.<br /><b>Conclusion</b><br />The LV anterolateral site is the preferred LV lead position in patients being upgraded from conventional RV apical pacing to CRT.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 14 Jul 2023; epub ahead of print</small></div>

<div><h4>Impact of filter configurations on bipolar EGMs: An optimal filter setting for identifying VT substrates.</h4><i>Takigawa M, Sacher F, Martin C, Cheniti G, ... Haissaguierre M, Jais P</i><br /><b>Background</b><br />The impact of filtering on bipolar electrograms (EGMs) has not been systematically examined. We tried to clarify the optimal filter configuration for ventricular tachycardia (VT) ablation.<br /><b>Methods</b><br />Fifteen patients with VT were included. Eight different filter configurations were prospectively created for the distal bipoles of the ablation catheter: 1.0-250, 10-250, 100-250, 30-50, 30-100, 30-250, 30-500, and 30-1000 Hz. Pre-ablation stable EGMs with good contact (contact force > 10 g) were analyzed. Baseline fluctuation, baseline noise, bipolar peak-to-peak voltage, and presence of local abnormal ventricular activity (LAVA) were compared between different filter configurations.<br /><b>Results</b><br />In total, 2276 EGMs with multiple bipolar configurations in 246 sites in scar and border areas were analyzed. Baseline fluctuation was only observed in the high-pass filter of (HPF) ≤ 10 Hz (p < .001). Noise level was lowest at 30-50 Hz (0.018 [0.012-0.029] mV), increased as the low-pass filter (LPF) extended, and was highest at 30-1000 Hz (0.047 [0.041-0.061] mV) (p < .001). Conversely, the HPF did not affect the noise level at ≤30 Hz. As the HPF extended to 100 Hz, bipolar voltages significantly decreased (p < .001), but were not affected when the LPF was extended to ≥100 Hz. LAVAs were most frequently detected at 30-250 Hz (207/246; 84.2%) and 30-500 Hz (208/246; 84.6%), followed by 30-1000 Hz (205/246; 83.3%), but frequently missed at LPF ≤ 100 Hz or HPF ≤ 10 Hz (p < .001). A 50-Hz notch-filter reduced the bipolar voltage by 43.9% and LAVA-detection by 34.5% (p < .0001).<br /><b>Conclusion</b><br />Bipolar EGMs are strongly affected by filter settings in scar/border areas. In all, 30-250 or 30-500 Hz may be the best configuration, minimizing the baseline fluctuation, baseline noise, and detecting LAVAs. Not applying the 50-Hz notch filter may be beneficial to avoid missing VT substrate.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 11 Jul 2023; epub ahead of print</small></div>

<div><h4>First worldwide use of pulsed-field ablation for ventricular tachycardia ablation via a retrograde approach.</h4><i>Martin CA, Zaw MT, Jackson N, Morris D, Costanzo P</i><br /><b>Introduction</b><br />We present the first worldwide use of pulsed-field ablation (PFA) for ventricular tachycardia (VT) ablation via a retrograde approach.<br /><b>Methods</b><br />The patient had previously failed conventional ablation of an intramural circuit underneath the aortic valve. The same VT circuit was inducible during the procedure. The Farawave PFA catheter and Faradrive sheath were used to deliver PFA applications.<br /><b>Results</b><br />Post ablation mapping demonstrated scar homogenization. There was no evidence of coronary spasm during PFA applications and no other complications occurred. VT was non-inducible post ablation and the patient has remained free of arrhythmia at follow-up.<br /><b>Conclusion</b><br />PFA for VT via a retrograde approach is feasible and effective.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 11 Jul 2023; epub ahead of print</small></div>

<div><h4>Novel streamlined technique for left atrial appendage closure using a radiofrequency wire-based large access system.</h4><i>Asfour IK, Elchouemi M, Gianni C, Helmy R, ... Natale A, Al-Ahmad A</i><br /><b>Introduction</b><br />Transseptal puncture (TSP) to allow for large delivery sheath left atrial (LA) access remains a challenging aspect of LA appendage closure (LAAC) in patients with prior history of TSP, thick or lipomatous septum, atrial septal aneurysms, or other complex cardiac anatomies. This study investigates the use of the VersaCross large access (VLA) system (Baylis Medical/Boston Scientific) to improve procedural efficiency of LAAC compared to the standard needle workflow.<br /><b>Methods and results</b><br />Fifty LAAC procedures using WATCHMAN FLX between November 2021 and September 2022 were retrospectively analyzed comparing the VLA workflow (n = 25) to the standard needle workflow (n = 25). Study primary endpoint was time to procedural efficiency, and secondary endpoints included TSP time, acute LAAC success, fluoroscopy use, device recaptures, and periprocedural complications. Acute LAAC was successfully completed in all cases with no intraprocedural complications. TSP time was faster, but not significant, using the VLA workflow compared to the standard RF needle workflow (2.6 ± 1.1 min vs. 3.0 ± 1.8 min, p = 0.38). Time to WATCHMAN sheath in LA from TSP was 27% faster (1.5 ± 0.8 min vs. 2.1 ± 0.9 min; p = 0.03), and time to WATCHMAN release from TSP was 19% faster (10.5. ± 2.5 min vs. 13.0 ± 3.7 min; p = 0.01) with the VLA workflow. Overall procedure time was 15% faster (30.4 ± 5.1 min vs. 36.0 ± 6.6 min; p = 0.003) using VLA. Fluoroscopy time was 25% lower (4.0 ± 2.2 min vs. 5.5 ± 2.3 min; p = 0.003) and fluoroscopy dose was 60% lower (97.0 ± 91.7 mGy vs. 241.8 ± 240.6 mGy; p = 0.01) and more consistent [F-test, p ˂ 0.0001] using the VLA workflow compared to the needle workflow.<br /><b>Conclusion</b><br />The VLA system streamlines LAAC procedures, improving LAAC efficiency and reducing fluoroscopy use by allowing for de novo dilation of the septum for large-bore delivery sheaths, and reducing device exchanges and delivery sheath manipulation.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 07 Jul 2023; epub ahead of print</small></div>

<div><h4>Left atrial appendage structural characteristics predict thrombus formation.</h4><i>Castellani C, Gao Y, Kim H, Thompson C, ... Welsh A, Berger M</i><br /><b>Introduction</b><br />Nonvalvular atrial fibrillation (NVAF) is a highly prevalent arrhythmia where loss of synchronized atrial contraction increases the risk of intracardiac thrombus particularly within the left atrial appendage (LAA). Anticoagulation is the mainstay of stroke prevention based on the CHA<sub>2</sub> DS<sub>2</sub> -VASc score; however, it does not account for LAA structural characteristics.<br /><b>Methods</b><br />The research comprises a retrospective matched case-control study of 196 subjects with NVAF who underwent transesophageal echo (TEE). The control group, without thrombus (n = 117), was selected from two different groups, both pools had: NVAF and CHA<sub>2</sub> DS<sub>2</sub> -VASc score ≥ 3. One group underwent screening TEE before Watchman closure device placement from January 2015 to December 2019 (n = 74) the second underwent TEE before cardioversion from February to October 2014 (n = 43). The study group, with thrombus (n = 79), included patients with NVAF, TEE study performed between February 2014 and December 2020, and LAA thrombus. The propensity score method was utilized to determine the matched controls while accounting for confounding from prognostic variables resulting in 61 matched pairs included in the analysis data set. LAA ostial area (OA) (calculated from orthogonal measurements 0°, 90° or 45°, 135°), LAA maximal depth, and peak LAA outflow velocity were measured.<br /><b>Results</b><br />Patient characteristics and TEE data were collected and compared using the t test or χ<sup>2</sup> analysis. We observed a lower LAA peak exit velocity in the thrombus group as compared to the control group. Additionally, we found that patients in the thrombus group had smaller LAA OA at 0° and 90°, at 45° and 135°, using largest diameter, as well as using aggregate OA, and smaller maximum LAA depth compared to patients in the control group. Candidate conditional logistic regression models for the outcome of the presence of thrombus were evaluated. Statistical results from the best-fitting conditional regression model were calculated showing a significant association between aggregate OA and LAA exit velocity with presence of thrombus.<br /><b>Conclusion</b><br />Utilizing LAA structural characteristics to predict thrombus formation may help refine current cardioembolic stroke (CES) risk estimation.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 05 Jul 2023; epub ahead of print</small></div>

<div><h4>In-vivo evaluation of catheter integrity with the use of a novel catheter torque tool.</h4><i>Mass P, Opfermann J, Grupposo RTV, DiBiase L, Berul CI, Clark BC</i><br /><b>Introduction</b><br />Electrophysiology studies and ablation procedures require strength, steadiness, and dexterity to manipulate catheters. We have previously described a novel catheter torque tool (Peritorq) that improves torqueability and stability and decreases user muscle fatigue. The objective was to evaluate measures of catheter integrity with and without the torque tool in place using multiple diagnostic and ablation catheters in an adult porcine model.<br /><b>Methods</b><br />Diagnostic and ablation catheters were inserted through the femoral or jugular vein into areas of the right atrium, coronary sinus (CS), and right ventricle. Electrical measurements including impedance, sensing, and capture thresholds were obtained with and without the torque tool. Ablation lesions (30 s) were given at different locations using both irrigated and nonirrigated catheters and measurements were recorded with and without the torque tool.<br /><b>Results</b><br />Procedures were performed in eight adult pigs. Measurements with and without the torque tool in all locations did not differ significantly using any of the catheters. With the nonirrigated ablation catheter there was a significant difference in maximum (mean 1.7 W, p = .03) and average power (mean 9.1 W, p = .04) delivery at the PS tricuspid valve, but there were no other differences with the irrigated or nonirrigated catheters. Subjective assessment by the operator revealed a substantial improvement in maneuverability, ability to transfer torque, and stability within the cardiac space.<br /><b>Conclusion</b><br />In an in-vivo environment, a novel catheter torque tool subjectively improved catheter manipulation and did not have a significant impact on the integrity of electrophysiologic catheters. Further study including additional catheters and in-vivo human testing is indicated.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 05 Jul 2023; epub ahead of print</small></div>

<div><h4>Differences between typical and reverse typical atrial flutter identified by ultrahigh resolution mapping.</h4><i>Hara S, Sato Y, Kusa S, Miwa N, ... Doi J, Hachiya H</i><br /><b>Background</b><br />Although atrial flutter (AFL) is a common arrhythmia that is based on a macro-reentrant tachycardia around the tricuspid annulus, the factors giving rise to typical AFL (t-AFL) versus reverse typical AFL (rt-AFL) are unknown. To investigate the difference between t-AFL and rt-AFL circuits using ultrahigh resolution mapping of the right atrium.<br /><b>Methods</b><br />We investigated 30 isthmus-dependent AFL patients (mean age 71, 28 male) who underwent first-time cavo-tricuspid isthmus (CTI) ablation guided by Boston Scientific\'s Rhythmia mapping system and divided them into two groups: t-AFL (22 patients) and rt-AFL (8 patients). We compared the anatomy and electrophysiology of their reentrant circuits.<br /><b>Results</b><br />Baseline patient characteristics, use of antiarrhythmic drugs, prevalence of atrial fibrillation, AFL cycle length (227.1 ± 21.4 vs. 245.5 ± 36.0 ms, p = .10), and CTI length (31.9 ± 8.3 vs. 31.1 ± 5.2 mm, p = .80) did not differ between the two groups. Functional block was observed at the crista terminalis in 16 patients and at the sinus venosus in 11. No functional block was observed in three patients, all of whom belonged to the rt-AFL group. That is, functional block was observed in 100% of the t-AFL group as opposed to 5/8 (62.5%) of the rt-AFL (p < .05). Slow conduction zones were frequently observed at the intra-atrial septum in the t-AFL group and at the CTI in the rt-AFL group.<br /><b>Conclusion</b><br />Mapping with ultrahigh-resolution mapping showed differences between t-AFL and rt-AFL in conduction properties in the right atrium and around the tricuspid valve, which suggested directional mechanisms.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 02 Jul 2023; epub ahead of print</small></div>

<div><h4>Association between residual unipolar voltage and arrhythmia recurrence after left atrial posterior wall isolation for persistent atrial fibrillation.</h4><i>Kujiraoka H, Hojo R, Arai T, Takahashi M, Fukamizu S</i><br /><b>Introduction</b><br />Posterior wall isolation (PWI) combined with pulmonary vein isolation (PVI) has proven effective for persistent atrial fibrillation (AF). However, when performing PWI, creating transmural lesions with subendocardial ablation is sometimes difficult. Endocardial unipolar voltage amplitude had a higher sensitivity than bipolar voltage mapping for identifying intramural viable myocardium in the atria. In this study, we aimed to retrospectively investigate the correlation between the residual potential in the posterior wall (PW) following PWI for persistent AF and atrial arrhythmia recurrence using endocardial unipolar voltage.<br /><b>Methods</b><br />This was a single-center observational study. Patients who underwent PVI and PWI for persistent AF in the first procedure between March 2018 and December 2021 at the Tokyo Metropolitan Hiroo Hospital were included in this study. The patients were divided into two groups based on the presence of residual unipolar PW potentials after PWI with a cutoff of 1.08 mV and the recurrence of atrial arrhythmias was compared.<br /><b>Results</b><br />In total, 109 patients were included in the analysis. Forty-three patients had residual unipolar potentials after PWI and 66 patients had no residual unipolar potentials. The atrial arrhythmia recurrence rate was significantly higher in the group with residual unipolar potential (41.8% vs. 17.9%, p = 0.003). The residual unipolar potential was an independent predictor of recurrence (odds ratio: 4.53; confidence interval: 1.67-12.3, p = 0.003).<br /><b>Conclusion</b><br />Residual unipolar potential after PWI for persistent AF is associated with recurrent atrial arrhythmias.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 02 Jul 2023; epub ahead of print</small></div>

<div><h4>Prospective randomized study comparing permanent pacing with rate drop response and closed loop stimulation in patients with vasovagal syncope where permanent pacing is indicated and selected as the appropriate treatment option.</h4><i>Prakash A, Sutton R</i><br /><b>Background</b><br />Pacing for vasovagal syncope is established. Two pacing algorithms are available. The rate-drop-response (RDR-Medtronic) is triggered by falling heart rate acting with modified rate-hysteresis. The closed loop stimulation or system (CLS-Biotronik) is triggered by impedance changes in the right ventricle reflecting falling volume and rising contractility. These are very different physiologically. Both algorithms carry favorable reports in clinical use.<br /><b>Methods</b><br />A randomized-controlled superiority trial is proposed to compare the two algorithms for the control of vasovagal syncope in patients for whom pacing is indicated by current guidelines in North America and Europe. Available recent evidence may be seen as supporting superiority of CLS. No comparison between the two algorithms has been made. In this trial, patients will be centrally randomized to one or other algorithm on a 1:1 basis. Two-hundred-seventy-six patients in each group will be recruited. Sample size is determined using a confidence interval of 95%, a power of 90%, and a drop-out rate of 10% to detect an 11% difference between CLS and RDR. Recurrent symptom comparison will be made by an independent committee. The Co-primary endpoints will be recurrent syncope burden compared with that in 24-months preimplant, and occurrence of syncope in 24-months follow-up. Each outcome will be compared between the two algorithms. Secondary endpoints will be program and drug therapy changes over 24-months follow-up and quality of life by questionnaire at baseline,1 and 2 years.<br /><b>Results and conclusions</b><br />These are anticipated to clarify the device algorithm choice and, therefore, to improve patient care.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 02 Jul 2023; epub ahead of print</small></div>

<div><h4>Arrhythmias induced by dextrose-insulin challenge test in nondiagnostic Brugada ECG patterns.</h4><i>Velázquez-Rodríguez E, Jiménez-Cruz JPM</i><br /><b>Introduction</b><br />Dynamic ECG changes in Brugada syndrome (BrS) are influenced by several factors, may not be apparent, and can be unmasked by a drug test.<br /><b>Methods and results</b><br />Four of six patients with nondiagnostic Brugada ECG index patterns underwent a dextrose-insulin challenge test that resulted in J-ST segment elevation and triggered arrhythmias.<br /><b>Conclusion</b><br />Insulin action may be due in part to an outward shift in the K<sup>+</sup> current at the end of action potential phase 1 and the dispersion of repolarization, leading to local re-entry with arrhythmogenicity. This effect is likely a phenomenon-specific to BrS.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 02 Jul 2023; epub ahead of print</small></div>

<div><h4>Injecting a ventricular tachycardia into the heart-Α unique case report.</h4><i>Kanoupakis EM, Plevritaki A, Koutalas EP, Lazopoulos GL, ... Koutentakis D, Kochiadakis GE</i><br /><b>Introduction</b><br />A 52-year-old woman presented with a complex ventricular arrhythmia in an intraoperative context, during kyphoplasty for an osteoporotic fracture of a lumbar vertebra. The subject showed no indications of a previous cardiovascular condition.<br /><b>Methods and results</b><br />Causes of arrhythmias associated with the procedure were excluded. Due to her positive family history for dilated cardiomyopathy, upcoming thoughts were made for unmasking a previous asymptomatic cardiomyopathy. Nevertheless, an intracardiac cement embolism was diagnosed and, finally, the patient underwent an open-heart surgery with successful removal of the cardiac cement. Νo new arrhythmia recorded during follow up.<br /><b>Conclusion</b><br />To the best of our knowledge, this is the first reported case of ventricular arrhythmogenic presentation of a cardiac cement embolus after a KP procedure.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 30 Jun 2023; epub ahead of print</small></div>

<div><h4>Sex-based differences in safety and efficacy of catheter ablation for atrial fibrillation.</h4><i>Yadav R, Milstein J, Blum J, Lazieh S, ... Calkins H, Spragg D</i><br /><b>Background</b><br />Studies have identified significant sex-based differences and disparities in the clinical presentation and treatment of atrial fibrillation (AF). Studies have shown women are less likely to be referred for catheter ablation, are older at the time of ablation, and are more likely to have recurrence after ablation. However, in most studies investigating AF ablation outcomes, the female cohorts were relatively small. The impact of sex on the outcome and safety of ablation procedures is still unclear.<br /><b>Objective</b><br />To investigate sex-based differences in outcomes and complications after AF catheter ablation, with a significant female cohort METHOD: In this retrospective study, patients undergoing AF ablation from January 1, 2014, to March 31, 2021, were included. We investigated clinical characteristics, duration and progression of AF, number of EP appointments from diagnosis to ablation, procedural data, and procedure complications.<br /><b>Results</b><br />Total of 1346 patients underwent first catheter ablation for AF during this period, including 896 (66.5%) male and 450 (33.4%) female patients. Female patients were older at the time of ablation (66.2 vs. 62.4 years; p < .001). Women had higher CHA<sub>2</sub> DS<sub>2</sub> -VASc (congestive heart failure, hypertension, age, diabetes, stroke, vascular disease, sex category) scores (3 vs. 2; p < .001) than men, expectedly, as the female sex warrants an additional point. 25.3% female patients had PersAF at the time of diagnosis versus 35.3% male patients (p < .001). At the time of ablation, 31.8% female patients had PersAF as compared to 43.1% male patients (p < .001), indicating progression of PAF to PersAF in both sexes. Women tried more AADs than men before ablation (1.13 vs. 0.98; p = .002). Male and female patients had no statistically significant difference in (a) arrhythmia recurrence at 1-year post ablation (27.7% vs. 30%; p = .38) or (b) procedural complication rate (1.8% vs. 3.1%; p = .56).<br /><b>Conclusion</b><br />Female patients were older and had higher CHA<sub>2</sub> DS<sub>2</sub> -VASc scores compared to males at the time of AF ablation. Women tried more AADs than men before ablation. One-year arrhythmia recurrence rates and procedural complications were similar in both sexes. No sex-based differences were observed in safety and efficacy of ablation.<br /><br />© 2023 Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 27 Jun 2023; epub ahead of print</small></div>

<div><h4>Spatial correlation of left atrial low voltage substrate in sinus rhythm versus atrial fibrillation: The rhythm specificity of atrial low voltage substrate.</h4><i>Nairn D, Eichenlaub M, Lehrmann H, Müller-Edenborn B, ... Jadidi A, Loewe A</i><br /><b>Introduction</b><br />Improved sinus rhythm (SR) maintenance rates have been achieved in patients with persistent atrial fibrillation (AF) undergoing pulmonary vein isolation plus additional ablation of low voltage substrate (LVS) during SR. However, voltage mapping during SR may be hindered in persistent and long-persistent AF patients by immediate AF recurrence after electrical cardioversion. We assess correlations between LVS extent and location during SR and AF, aiming to identify regional voltage thresholds for rhythm-independent delineation/detection of LVS areas. (1) Identification of voltage dissimilarities between mapping in SR and AF. (2) Identification of regional voltage thresholds that improve cross-rhythm substrate detection. (3) Comparison of LVS between SR and native versus induced AF.<br /><b>Methods</b><br />Forty-one ablation-naive persistent AF patients underwent high-definition (1 mm electrodes; >1200 left atrial (LA) mapping sites per rhythm) voltage mapping in SR and AF. Global and regional voltage thresholds in AF were identified which best match LVS < 0.5 mV and <1.0 mV in SR. Additionally, the correlation between SR-LVS with induced versus native AF-LVS was assessed.<br /><b>Results</b><br />Substantial voltage differences (median: 0.52, interquartile range: 0.33-0.69, maximum: 1.19 mV) with a predominance of the posterior/inferior LA wall exist between the rhythms. An AF threshold of 0.34 mV for the entire left atrium provides an accuracy, sensitivity and specificity of 69%, 67%, and 69% to identify SR-LVS < 0.5 mV, respectively. Lower thresholds for the posterior wall (0.27 mV) and inferior wall (0.3 mV) result in higher spatial concordance to SR-LVS (4% and 7% increase). Concordance with SR-LVS was higher for induced AF compared to native AF (area under the curve[AUC]: 0.80 vs. 0.73). AF-LVS < 0.5 mV corresponds to SR-LVS < 0.97 mV (AUC: 0.73).<br /><b>Conclusion</b><br />Although the proposed region-specific voltage thresholds during AF improve the consistency of LVS identification as determined during SR, the concordance in LVS between SR and AF remains moderate, with larger LVS detection during AF. Voltage-based substrate ablation should preferentially be performed during SR to limit the amount of ablated atrial myocardium.<br /><br />© 2023 The Authors. Journal of Cardiovascular Electrophysiology published by Wiley Periodicals LLC.<br /><br /><small>J Cardiovasc Electrophysiol: 27 Jun 2023; epub ahead of print</small></div>