Late results after stand-alone surgical ablation for atrial fibrillation

doi:10.1016/j.jtcvs.2021.03.109

The Journal of Thoracic and Cardiovascular Surgery

Volume 164, Issue 5, November 2022, Pages 1515-1528.e8

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Abstract

Objectives

Stand-alone surgical ablation of atrial fibrillation is indicated in patients with refractory atrial fibrillation who have failed medical or catheter-based ablation. Few reports of late outcomes after stand-alone surgical ablation exist using comprehensive follow-up with strict definitions of success. This study examined our late outcomes of the stand-alone Cox-Maze IV procedure.

Methods

Between January 2003 and December 2019, 236 patients underwent a stand-alone Cox-Maze IV for refractory atrial fibrillation. Freedom from atrial tachyarrhythmias was assessed by electrocardiography, Holter, or pacemaker interrogation for up to 10 years, with a mean follow-up of 4.8 ± 3.5 years. Rhythm outcomes were compared in multiple subgroups. Factors associated with recurrence were determined using Fine-Gray regression, allowing for death as the competing risk.

Results

The majority of patients (176/236, 75%) had nonparoxysmal atrial fibrillation. Median duration of preoperative atrial fibrillation was 6.2 years (interquartile range, 3-11). Fifty-nine percent of patients (140/236) failed 1 or more prior catheter-based ablation. Thirteen patients (6%) experienced a major complication. There was no 30-day mortality. Freedom from atrial tachyarrhythmias was 94% (187/199), 89% (81/91), and 77% (24/31) at 1, 5, and 10 years, respectively. There was no difference in freedom from atrial tachyarrhythmias between patients with paroxysmal atrial fibrillation versus nonparoxysmal atrial fibrillation (P > .05) or those undergoing sternotomy versus a minimally invasive approach (P > .05). Increased left atrial size and number of catheter ablations were associated with late atrial fibrillation recurrence. For patients who experienced any atrial tachyarrhythmia recurrence, the median number of recurrences was 1.5 (1.0-3.0).

Conclusions

The stand-alone Cox-Maze IV had excellent late efficacy at maintaining sinus rhythm in patients with symptomatic, refractory atrial fibrillation, with low morbidity and no mortality. The Cox-Maze IV, in contrast to catheter-based ablation, was equally effective in patients with paroxysmal and nonparoxysmal atrial fibrillation.

Graphical abstract

Overview of study design including total number of study patients undergoing stand-alone CMP-IV procedure with full box lesion set for symptomatic AF (n = 236). Patients were divided into 2 cohorts: paroxysmal AF (n = 60) and nonparoxysmal AF (n = 176). Primary outcome was incidence of first ATA recurrence. Stand-alone CMP-IV had excellent results at late follow-up, with low morbidity and no mortality. By competing-risk analysis, there was no difference in the incidence of first ATA recurrence between patients with paroxysmal and nonparoxysmal AF, and patients who underwent median sternotomy and RMT.

Section snippets

Materials and Methods

This study was approved by the Washington University School of Medicine Institutional Review Board. Informed consent and permission for release of information were obtained from all patients. The data were prospectively entered into a longitudinal database maintained at our institution, including demographic data, operative details, and perioperative results using Society of Thoracic Society definitions for complications. Rhythm and other follow-up data were prospectively entered into our

Patient Demographics

The overall mean age of patients at the time of stand-alone CMP-IV was 59.0 ± 10.4 years. In the entire cohort, 25% (60/236) had paroxysmal AF and 75% (176/236) had nonparoxysmal AF, of whom 91% (161/176) had long-standing persistent AF. Compared with patients with paroxysmal AF, patients with nonparoxysmal AF were older (60.1 ± 10.1 years vs 55.9 ± 10.7 years, P = .007) and more likely to be male (127/176 [72%] vs 32/60 [63%], P = .010; Table 1). No statistically significant differences

Discussion

The CMP remains the most effective surgical treatment of AF with the highest success rate of any interventional procedure.3, 4, 5, 6^,8, 9, 10, 11^,²³ The CMP-IV was developed after ablation devices allowed for a technically faster and less-invasive surgical approaches, and has been shown to be equally effective in patients with paroxysmal and nonparoxysmal AF.¹⁰^,¹¹ The stand-alone CMP-IV is effective in patients with lone AF at early follow-up, although few reports exist investigating late

Conclusions

The stand-alone CMP-IV was excellent at maintaining normal SR at late follow-up and remains the most successful interventional treatment of AF. The stand-alone CMP-IV was equally effective in patients with paroxysmal and nonparoxysmal AF, as well as those undergoing median sternotomy compared with a minimally invasive approach. There was a low rate of morbidity and no 30-day mortality after the procedure. There were no late strokes. On Fine-Gray regression, increased left atrial size and number

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Surgical ablation for atrial fibrillation is efficacious in patients with giant left atria
2024, Journal of Thoracic and Cardiovascular Surgery
The Cox-Maze IV procedure (CMP-IV) is the most effective treatment for atrial fibrillation. Increased left atrial (LA) size has been identified as a risk factor for failure to restore sinus rhythm. This has biased many surgeons against ablation in patients with giant left atrium (GLA), defined as LA diameter >6.5 cm. In this study we aimed to define the efficacy of the CMP-IV in patients with GLA.
From April 2004 through March 2020, 786 patients with a documented LA diameter underwent elective CMP-IV, 72 of whom had GLA. Median follow-up duration was 4 years (interquartile range, 1-7 years). Recurrence was defined as any documented atrial tachyarrhythmia (ATA) lasting 30 seconds. ATA recurrence and survival were analyzed across GLA versus non-GLA groups.
Median age at surgery was 65 (interquartile range, 56-73) years. Median LA diameter within the GLA group was 7.0 (range, 6.6-10.0) cm. There were no differences in rates of postoperative complications for the 2 groups, including rate of postoperative stroke and pacemaker placement (GLA 14%; non-GLA 12%; P = .682). A trend toward increased 30-day mortality in the GLA group did not reach statistical significance (GLA 6%; non-GLA 2%; P = .051). Freedom from ATAs at 5 years postoperatively was comparable for the 2 groups (GLA 82%; non-GLA 84%).
The CMP-IV had good efficacy in patients with GLA. Our results suggest that LA diameter >6.5 cm should not preclude a patient from undergoing surgical ablation for atrial fibrillation.
Robotic-assisted cryothermic Cox maze for persistent atrial fibrillation: Longitudinal follow-up
2023, Journal of Thoracic and Cardiovascular Surgery
Citation Excerpt :
Previous experiences with robotic mitral surgery have documented use of cryoablation, but the lesions performed were not consistent or biatrial, nor has longitudinal rhythm follow-up been documented.23 Although minimally invasive hybrid surgical-catheter ablation solutions might indeed have a role in AF management, for long-standing persistent AF patients with or without structural disease, a full biatrial Cox maze III/IV (Figure 2), performed using a minithoracotomy or sternotomy approach, has shown optimal safety and effectiveness.4,5,11,12,15-18 For the management of patients with persistent AF, in the current study we examined the safety and efficacy of a robotic-assisted Cox maze, performed via a single right lateral minithoracotomy.
Surgical ablation of atrial fibrillation (AF) is recommended as a stand-alone therapy for patients refractory to medical or catheter-based treatment, or as a concomitant therapy when associated with structural disease. We report a single-therapy robotic approach to the Cox maze with longitudinal follow-up.
Consecutive patients who underwent robotic biatrial cryothermic Cox maze for nonparoxysmal AF between November 2016 and January 2022 were examined at 1, 2, 3, 6, 9, 12, 18, 24, 36, 48, and 60 months. Freedom from atrial tachyarrhythmia was assessed with 24-hour continuous electrocardiogram or pacemaker interrogation in all patients after 6 months. Mean follow-up was 17 ± 14.5 months (range, 1-60 months). Time to event analysis with competing risks was used to determine risk-adjusted associations with late outcomes.
Patients (n = 135) had a median AF duration of 4.0 years (interquartile range, 0.8-7.0), with 29.6% in whom 1 or more catheter ablations had failed. Stand-alone maze was performed in 25.2%, whereas 61.4% underwent concomitant robotic mitral valve surgery, 7.4% tricuspid valve repair, and 4.4% aortic valve replacement. No patients were discharged in AF. There were 3 operative mortalities (2.2%), none in stand-alone patients. One patient required catheter ablation at 8 months postoperatively, and one had a nonembolic stroke at 18 months. There were 9 late deaths. Freedom from atrial tachyarrhythmia and antiarrhythmic drugs at 9, 12, 18, 24, 36, and 48 months was 97.0%, 96.7%, 98.1%, 97.1%, and 100%, respectively. Lower ejection fraction and need for concomitant mitral valve replacement and/or aortic valve replacement were independently associated with worse survival.
For persistent AF, robotic biatrial cryothermic Cox maze offered greater than 90% 1-year longitudinal freedom from stroke, oral anticoagulation, repeat ablation, and recurrent AF without the need for antiarrhythmic drugs.
Commentary: The curse of missing long-term data in cardiac surgery
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Non-Pharmacological Stroke Prevention in Atrial Fibrillation
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Predictors of pacemaker implantation within three months after catheter ablation of atrial fibrillation
2023, PACE - Pacing and Clinical Electrophysiology

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: This work was supported by the National Institutes of Health, RO1-HL032257 to R.J.D. and R.B.S., T32-HL007776 to R.J.D., R.M.M., and M.O.K., and the Barnes-Jewish Foundation.

: Washington University School of Medicine Institutional Review Board ID #201105322, current approval date: December 18, 2018.

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Adult: ArrhythmiasLate results after stand-alone surgical ablation for atrial fibrillation

Abstract

Objectives

Methods

Results

Conclusions

Graphical abstract

Section snippets

Materials and Methods

Patient Demographics

Discussion

Conclusions

Ann Thorac Surg

J Thorac Cardiovasc Surg

Semin Thorac Cardiovasc Surg

Semin Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

Ann Thorac Surg

Ann Thorac Surg

Ann Thorac Surg

Ann Thorac Surg

Opera Tech Thorac Cardiovasc Surg

Heart Rhythm

J Thorac Cardiovasc Surg

J Thorac Cardiovasc Surg

Heart Rhythm

J Thorac Cardiovasc Surg

Adult: Arrhythmias
Late results after stand-alone surgical ablation for atrial fibrillation