<div><h4>Diagnostic and prognostic value of the sex-specific 99th percentile of four high-sensitivity cardiac troponin assays in patients with suspected myocardial infarction.</h4><i>Lehmacher J, Sörensen NA, Twerenbold R, Goßling A, ... Westermann D, Neumann JT</i><br /><b>Background</b><br />High-sensitivity cardiac troponin (hs-cTn) assays are used for detection of myocardial infarction (MI). 99th percentiles show wide inter-assay variation. Use of sex-specific cutoffs is recommended as definitory cutoff for MI. We compared diagnostic performance and prognostic value of sex-specific 99th percentiles of four hs-cTn assays in patients with suspected MI.<br /><b>Methods</b><br />Concentrations of four hs-cTn assays were measured at presentation and after 3 hours in patients with suspected MI. Final diagnoses were adjudicated according to 4th UDMI. Unisex and sex-specific 99th percentiles were evaluated as diagnostic cutoffs following the ESC 0/3h algorithm. These cutoffs were used in Cox-regression analyses to investigate the association with a composite endpoint of MI, revascularization, cardiac rehospitalization and death.<br /><b>Results</b><br />Non-ST-elevation MI was diagnosed in 368 of 2,718 patients. Applying the unisex 99th percentile, Elecsys hs-cTnT provided highest negative predictive value (NPV) of 99.7 and a positive predictive value (PPV) of 75.9. The analyzed hs-cTnI assays showed slightly lower NPVs and comparable PPVs (Architect [NPV 98.0, PPV 71.4]; Atellica [NPV 97.7, PPV of 76.1]; Pathfast [NPV 97.7, PPV of 66.6]). Application of sex-specific 99th percentiles did not significantly affect diagnostic performance. Concentrations above 99th percentile were independent predictors for impaired long-term outcome (hazard ratios 1.2 - 1.5, p<0.001).<br /><b>Conclusion</b><br />We describe a good diagnostic accuracy of four hs-cTn assay using the assay-specific 99th percentile for detection of MI. Application of sex-specific 99th percentiles did neither affect diagnostic performance nor prognostic value significantly. Finally, values above the 99th percentile were associated with poor long-term outcome.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 27 Oct 2023; epub ahead of print</small></div>

<div><h4>Organ perfusion pressure at admission and clinical outcomes in patients hospitalized for acute heart failure.</h4><i>Bocchino PP, Cingolani M, Frea S, Angelini F, ... Morici N, De Ferrari GM</i><br /><b>Background</b><br />Hypoperfusion portends adverse outcomes in acute heart failure (AHF). The gradient between end-organ inflow and outflow pressures may more closely reflect hypoperfusion than mean arterial pressure (MAP) alone. The aim of this study was to investigate organ perfusion pressure (OPP), calculated as MAP minus central venous pressure (CVP), as a prognostic marker in AHF.<br /><b>Methods</b><br />The SNIP-AHF study was a multicenter retrospective cohort study of 200 consecutive patients hospitalized for AHF treated with sodium nitroprusside. Only patients with both MAP and invasive CVP data available from the SNIP-AHF cohort were included in this analysis. The primary endpoint was to assess OPP as a predictor of worsening heart failure (WHF), defined as the worsening of signs and symptoms of heart failure leading to intensification of therapy at 48 hours.<br /><b>Results</b><br />146 patients fulfilling the inclusion criteria were included (mean age: 61.1 ± 13.5 years, 32 [21.9%] females; mean body mass index: 26.2 ± 11.7 kg/m2; mean left ventricular ejection fraction: 23.8%±11.4%, mean MAP: 80.2 ± 13.2 mmHg, mean CVP: 14.0 ± 6.1 mmHg). WHF occurred in 14 (9.6%) patients. At multivariable models including hemodynamic variables (OPP, shock index and CVP), OPP at admission was the best predictor of WHF at 48 hours (OR 0.91 [95%CI 0.86-0.96], p-value = 0.001) with an optimal cut-off value of 67.5 mmHg (specificity 47.3%, sensitivity 100%, AUC 0.784 ± 0.054). In multivariable models including univariable significant parameters available at first bedside assessment, namely New York Heart Association functional class, OPP, shock index, CVP and left ventricular end-diastolic diameter, OPP consistently and significantly predicted WHF at 48 hours.<br /><b>Conclusions</b><br />In this retrospective analysis on patients hospitalized for AHF treated with sodium nitroprusside, on-admission OPP significantly predicted WHF at 48 hours with high sensitivity.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 26 Oct 2023; epub ahead of print</small></div>

<div><h4>A Bayesian re-analysis of the INCEPTION-trial.</h4><i>Heuts S, van de Koolwijk AF, Gabrio A, Ubben JFH, ... Lorusso R, van de Poll MCG</i><br /><b>Background</b><br />Previously, we performed the multicenter INCEPTION-trial, randomizing patients with refractory out-of-hospital cardiac arrest to extracorporeal CPR (ECPR) or conventional CPR (CCPR). Frequentist analysis showed no statistically significant treatment effect for the primary outcome; 30-day survival with favorable neurologic outcome (Cerebral Performance Category score 1-2). To facilitate a probabilistic interpretation of the results, we present a Bayesian re-analysis of the INCEPTION-trial.<br /><b>Methods</b><br />We analyzed survival with favorable neurologic outcome at 30 days and 6 months under a minimally informative prior in the intention-to-treat population. Effect sizes are presented as absolute risk differences (ARD) and relative risks (RR), with 95% credible intervals (CrI). We estimated posterior probabilities at various thresholds, including the minimal clinically important difference (5% ARD), based on expert consensus, and performed sensitivity analyses under a skeptical and literature-based priors.<br /><b>Results</b><br />The mean ARD for 30-day survival with favorable neurologic outcome was 3.6% (95% CrI -9.5-16.7%), favoring ECPR, with a median RR of 1.22 (95% CrI 0.59-2.51). The posterior probability of a minimal clinically important difference was 42% at 30 days and 42% at 6 months, in favor of ECPR. The probability of any harm at 30 days was 29% and 35% under a minimally-informative and skeptical prior, and <6% under both informative priors.<br /><b>Conclusion</b><br />Bayesian re-analysis of the INCEPTION-trial estimated a 42% probability of a minimal clinically important difference between ECPR and CCPR in refractory OHCA in terms of 30-day survival with favorable neurologic outcome.<br /><b>Trial registration</b><br />Clinicaltrials.gov (NCT03101787, registered April 5th 2017).<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 24 Oct 2023; epub ahead of print</small></div>

<div><h4>Absence of visible infarction on cardiac magnetic resonance imaging despite the established diagnosis of myocardial infarction by 4th UDMI definition.</h4><i>Salatzki J, Giannitsis E, Hegenbarth A, Mueller-Hennessen M, ... Frey N, Biener M</i><br /><b>Background</b><br />Myocardial scarring due to acute myocardial infarction (AMI) can be visualized by Late Gadolinium Enhancement (LGE) on cardiac magnetic resonance imaging (CMR). However, a recent study revealed a group of type 1 AMI patients with undetectable myocardial injury on LGE. This study aims to describe these cases in detail and explore possible explanations for this new phenomenon.<br /><b>Methods</b><br />137 patients diagnosed with either ST-elevation (STEMI) or non-ST-elevation myocardial infarction (non-STEMI) diagnosed according to the 4th Universal Definition of Myocardial Infarction, underwent LGE-CMR after invasive coronary angiography (ICA). Fourteen of them (10.2%) showed no LGE and were included in the final study population.<br /><b>Results</b><br />Most patients presented with acute chest pain, three patients were diagnosed as STEMI and eleven as non-STEMI. Peak high-sensitivity cardiac troponin T (hs-TnT) ranged from 45 to 1173 ng/L. A culprit lesion was identified in 12 patients. Severe coronary stenoses were found in five patients, while seven patients had subtotal to total coronary artery occlusion. Percutaneous coronary intervention (PCI) was performed in 10 patients, while two patients required coronary artery bypass grafting (CABG) and no intervention was required in two patients. CMR was performed 30 (4-140) days after the initial presentation. Most patients showed preserved left ventricular (LV) ejection fraction on CMR. No alternative reasons for the rise/fall of hs-cTnT were found.<br /><b>Conclusion</b><br />The absence of LGE on CMR in patients with type 1 AMI is a new finding. While insufficient spatial resolution of LGE imaging, delayed CMR performance, spontaneous reperfusion, and coronary collaterals may provide some explanations, further investigations are required to fully understand this phenomenon.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 24 Oct 2023; epub ahead of print</small></div>

<div><h4>Complications in patients with cardiogenic shock on veno-arterial extracorporeal membrane oxygenation therapy: distribution and relevance. Results from an international, multicentre cohort study.</h4><i>Beer BN, Kellner C, Goßling A, Sundermeyer J, ... Westermann D, Schrage B</i><br /><b>Background</b><br />VA-ECMO restores circulation and tissue oxygenation in cardiogenic shock (CS) patients, but can also lead to complications.<br /><b>Objectives</b><br />To quantify VA-ECMO complications and analyse their association with overall survival as well as favourable neurological outcome (CPC 1 + 2).<br /><b>Methods</b><br />All-comer patients with CS treated with VA-ECMO were retrospectively enrolled from 16 centres in 4 countries (2005-2019). Neurological, bleeding and ischaemic adverse events (AEs) were considered. From these, typical VA-ECMO complications were identified and analysed separately as device-related complications.<br /><b>Results</b><br />N = 501. 118 were women (24%), median age was 56.0 years, median lactate 8.1 mmol/l. Acute myocardial infarction caused CS in 289 patients (58%). 30-day mortality was 40% (198/501 patients). At least one device-related complication occurred in 252/486 (52%) patients, neurological AEs in 108/469 (23%), bleeding in 192/480 (40%), ischaemic AEs in 123/478 (26%). The 22% of patients with the most AEs accounted for 50% of all AEs. All types of AEs were associated with a worse prognosis. Aside from neurological ones, all AEs and device-related complications were more likely to occur in women; although prediction of AEs outside of neurological AEs was generally poor.<br /><b>Conclusions</b><br />Therapy and device-related complications occur in half of all patients treated with VA-ECMO and are associated with a worse prognosis. They accumulate in some patients, especially in women. Aside from neurological events, identification of patients at risk is difficult, highlighting the need to establish additional quantitative markers of complication risk to guide VA-ECMO treatment in CS.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 24 Oct 2023; epub ahead of print</small></div>

<div><h4>Quality Control to improve low-density lipoprotein cholesterol management in patients with acute coronary syndromes based on the ACS EuroPath IV project.</h4><i>Schiele F, Catapano AL, De Caterina R, Laufs U, ... Zaman A, Sionis A</i><br /><b>Background</b><br />We performed quality control of lipid-lowering therapy (LLT) in patients with acute coronary syndrome, with a view to proposing corrective actions.<br /><b>Methods</b><br />Using a Define-Measure-Analysis-Improve-Control (DMAIC) approach applied to data from the ACS EuroPath IV survey, we measured attainment of two Quality Indicators (QIs) related to lipid lowering treatment: (1) prescription of high intensity statins (or equipotent treatment) before discharge, and (2) proportion with LDL-c < 55 mg/dL (1.4 mmol/L)) during follow-up. A total of 530 European cardiologists responded and provided data for up to 5 patients from their center, for acute and follow-up phases. Corrective measures are proposed to increase the rate of attainment of both QIs.<br /><b>Results</b><br />Attainment of the first QI was measured in 929 acute phase patients, 99% had LLT prescribed at discharge and 75% of patients fulfilled the first QI. Attainment of the second QI was assessed in 1721 patients with follow-up. The second QI was reached in 31% of patients. The DMAIC approach yielded ten potential changes in prescription, three for the first and seven for the second QI. The overall strategy is \"Fire and Target\", i.e. early intensification of the LLT using statins, ezetimibe, bempedoic acid and proprotein convertase subtilisin/kexin type-9 inhibitors, and is presented as an algorithm for routine application.<br /><b>Conclusion</b><br />Quality Control for LLT, based on the ACS EuroPath IV survey, detected ten potential changes in prescription that could enhance attainment of two QIs. Whether the \"Fire and Target\" strategy will be adopted and effective needs to be assessed in further steps of the EuroPath Quality Program.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 13 Oct 2023; epub ahead of print</small></div>

<div><h4>Coronary Calcification In Patients Presenting With Acute Coronary Syndromes: Insights From The Matrix Trial.</h4><i>Sanz Sánchez J, Garcia-Garcia HM, Branca M, Frigoli E, ... Vranckx P, Valgimigli M</i><br /><b>Objective</b><br />The role of coronary calcification on clinical outcomes among different revascularization strategies in patients presenting with acute coronary syndromes (ACS) has been rarely investigated. The aim of this investigation is to evaluate the role of coronary calcification, detected by coronary angiography, in the whole spectrum of patients presenting with acute ACS.<br /><b>Methods</b><br />The present study was a post hoc analysis of the MATRIX program. The primary endpoint was major adverse cardiovascular events (MACE), defined as the composite of all-cause mortality, myocardial infarction (MI), or stroke up to 365 days.<br /><b>Results</b><br />Among the 8,404 patients randomized in the MATRIX trial, data about coronary calcification was available in 7446 (88.6%) and therefore were included in this post-hoc analysis. Overall, 875 patients (11.7%) presented with severe coronary calcification, while 6,571 patients (88.3%) did not present severe coronary calcification on coronary angiography. Fewer patients with severe coronary calcification underwent percutaneous coronary intervention whereas coronary artery bypass grafting or medical therapy-only was more frequent compared with patients without severe calcification. At 1-year follow-up, MACE occurred in 237 (27.1%) patients with severe calcified coronary lesions and 985 (15%) patients without severe coronary calcified lesions [HR 1.91; 95% CI 1.66-2.20, p < 0.001]. All-cause mortality was 8.6% in patients presenting with and 3.7% in those without severe coronary calcification (HR 2.38, 1.84-3.09; p < 0.001). Patients with severe coronary calcification incurred higher rate of MI (20.1% vs 11.5%, HR 1.81; 95% CI 1.53-2.1, p < 0.001) and similar rate of stroke (0.8% vs 0.6%, HR 1.35; 95% CI 0.61-3.02, p = 0.46).<br /><b>Conclusions</b><br />Patients with ACS and severe coronary calcification, as compared to those without, are associated with worse clinical outcomes irrespective of the management strategy.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 09 Oct 2023; epub ahead of print</small></div>

<div><h4>Discovery of plasma proteins associated with ventricular fibrillation during first ST-elevation myocardial infarction via proteomics.</h4><i>Stampe NK, Ottenheijm ME, Drici L, Wewer Albrechtsen NJ, ... Tfelt-Hansen J, Glinge C</i><br /><b>Background:</b><br/>and aims</b><br />The underlying biological mechanisms of ventricular fibrillation (VF) during acute myocardial infarction are largely unknown. To our knowledge, this is the first proteomic study for this trait, with the aim to identify and characterize proteins that are associated with VF during first ST-elevation myocardial infarction (STEMI).<br /><b>Methods</b><br />We included 230 participants from a Danish ongoing case-control study on patients with first STEMI with VF (case, n = 110) and without VF (control, n = 120) before guided catheter insertion for primary percutaneous coronary intervention. The plasma proteome was investigated using mass spectrometry-based proteomics on plasma samples collected within 24 hours of symptom onset.<br /><b>Results</b><br />In 229 STEMI patients (72% men, median age 62 years (interquartile range (IQR): 54-70)), a median of 257 proteins (IQR: 244-281) were quantified per patient. A total of 26 proteins were associated with VF, these proteins were involved in several biological processes including blood coagulation, hemostasis, and immunity. After correcting for multiple testing, two up-regulated proteins remained significantly associated with VF, actin beta-like 2 (ACTBL2, fold-change (FC) 2.25, p < 0.001, q = 0.023) and coagulation factor XIII-A (F13A1, FC 1.48, p < 0.001, q = 0.023). None of the proteins were correlated with anterior infarct location.<br /><b>Conclusion</b><br />VF due to first STEMI was significantly associated with two up-regulated proteins (ACTBL2 and F13A1), suggesting that they may represent novel underlying molecular VF mechanisms. Further research is needed to determine whether these proteins are predictive biomarkers or acute phase response proteins to VF during acute ischemia.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 09 Oct 2023; epub ahead of print</small></div>

<div><h4>Percutaneous Coronary Intervention for ST-elevation Myocardial Infarction Complicated by Cardiogenic Shock in a Super-aging Society.</h4><i>Nishihira K, Honda S, Takegami M, Kojima S, ... Kimura K, Yasuda S</i><br /><b>Aims</b><br />ST-segment elevation myocardial infarction complicated by cardiogenic shock (STEMICS) is associated with substantial mortality. As life expectancy increases, percutaneous coronary intervention (PCI) is being performed more frequently, even in elderly patients with acute myocardial infarction (AMI). This study sought to investigate the characteristics and impact of PCI on in-hospital mortality in patients with STEMICS.<br /><b>Methods and results</b><br />The Japan AMI Registry (JAMIR) is a retrospective, nationwide, real-world database. Among 46,242 patients with AMI hospitalized in 2011-2016, 2,760 patients with STEMICS (median age, 72 years) were studied. We compared 2,396 (86.8%) patients who underwent PCI with 364 (13.2%) patients who did not. The percentage of mechanical circulatory support use in patients with STEMICS was 69.3% and in-hospital mortality was 34.6%. Compared with patients who did not undergo PCI, patients undergoing PCI were younger and had a higher rate of intra-aortic balloon pump use. A higher proportion were male or current smokers. In-hospital mortality was significantly lower in the PCI group than in the no-PCI group (31.3% vs. 56.0%, P < 0.001). PCI was independently associated with lower in-hospital mortality (adjusted odds ratio [OR], 0.508; 95% confidence interval [CI], 0.347-0.744). In 789 (28.6%) patients aged ≥80 years, PCI was associated with fewer in-hospital cardiac deaths (adjusted OR, 0.524; 95% CI, 0.281-0.975), but was not associated with in-hospital mortality (adjusted OR, 0.564; 95% CI, 0.300-1.050).<br /><b>Conclusion</b><br />In Japan, PCI was effective in reducing in-hospital cardiac death in elderly patients with STEMICS. Age alone should not preclude potentially beneficial invasive therapy.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 19 Sep 2023; epub ahead of print</small></div>

<div><h4>Incidence, management, and prognostic impact of arrhythmias in patients with Takotsubo syndrome: a nationwide retrospective cohort study.</h4><i>Isogai T, Matsui H, Tanaka H, Makito K, Fushimi K, Yasunaga H</i><br /><b>Background</b><br />Arrhythmia is a major complication of Takotsubo syndrome (TTS). However, its incidence, management, and prognostic impact remain to be elucidated in a large cohort.<br /><b>Methods</b><br />We retrospectively identified 16713 patients hospitalized for TTS between July 2010 and March 2021 from the Japanese Diagnosis Procedure Combination database. Serious arrhythmias were defined as ventricular tachycardia/fibrillation (VT/VF), 2nd/3rd-degree atrioventricular block (AVB), sick sinus syndrome (SSS), or unspecified arrhythmias requiring device treatment. Patient characteristics and outcomes were compared based on the occurrence of serious arrhythmias.<br /><b>Results</b><br />The overall incidence proportion of serious arrhythmias was 6.2% (n=1036; 449 VT/VF, 283 2nd/3rd-degree AVB, 133 SSS, 55 multiple arrhythmias, 116 others), which remained stable over 11 years. The arrhythmia group was younger, more often male, and exhibited greater impairment in activities of daily living (ADLs) and consciousness than the non-arrhythmia group. Although crude in-hospital mortality was higher in the arrhythmia group (9.6% vs. 5.0%, p=0.013), the significant association between arrhythmias and mortality disappeared after adjustment for confounders (odds ratio=1.15, 95% CI=0.90-1.49). However, age, sex, ADLs, consciousness, and Charlson comorbidity index were significantly associated with mortality. In the arrhythmia group, 254 (24.5%) patients received pacemakers (18.4%) or defibrillators (6.1%), which were implanted at a median of 8 and 19 days after admission, respectively.<br /><b>Conclusions</b><br />Arrhythmias are not uncommon in TTS. Patients\' background characteristics, rather than arrhythmia itself, may be associated with in-hospital mortality. Given the reversibility of cardiac dysfunction in TTS, there may be unnecessary device implantations for arrhythmias occurring as sequelae to TTS, warranting further investigations.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 15 Sep 2023; epub ahead of print</small></div>

<div><h4>Multidisciplinary cardiogenic shock team approach improves the long-term outcomes of patients suffering from refractory cardiogenic shock treated with short-term mechanical circulatory support.</h4><i>Hérion FX, Beurton A, Oddos C, Nubret K, ... Imbault J, Ouattara A</i><br /><b>Background</b><br />Short-term mechanical circulatory support (STMCS) may be used as an intentional escalation strategy to treat cardiogenic shock refractory (rCS). However, with growing technical possibilities, making the right choice at the right time can be challenging. We established a shock team in January 2013 comprising a cardiac anaesthetist-intensivist, an interventional cardiologist, and a cardiac surgeon. Since then, a diagnosis of rCS has triggered a multidisciplinary team meeting based on a common algorithm. This study aimed to compare the decision-making process for STMCS for rCS before (2007-2013) and after (2013-2019) the creation of the shock team.<br /><b>Methods</b><br />This before-and-after cohort study was conducted over a 156-month period. Post-cardiotomy rCS were excluded. The primary outcome was a 1-year survival rate.<br /><b>Results</b><br />In total, 250 consecutive adult patients were included in the analysis (84 in the control group and 166 in the shock team group). At baseline, the CardShock score was not different between the two groups (5[3-5] vs. 5[4-6], p=0.323). The 1-year survival rate was significantly higher in the shock team group compared to the control group (59% vs. 45%, p = 0.043). After a Cox regression analysis, the shock team intervention was independently associated with a significantly improved 1-year survival rate (HR: 0.592, 95% CI: 0.398-0.880, p=0.010).<br /><b>Conclusion</b><br />A multidisciplinary shock team-based decision for STMCS device implantation in rCS is associated with better 1-year survival rates.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 15 Sep 2023; epub ahead of print</small></div>

<div><h4>Air Pollution and out-of-hospital cardiac arrest risk.</h4><i>Moderato L, Aschieri D, Lazzeroni D, Rossi L, ... Nicolini F, Niccoli G</i><br /><b>Background</b><br />Globally nearly 20% of cardiovascular disease deaths were attributable to air pollution. Out-of-hospital cardiac arrest (OHCA) represents a major public health problem, therefore, the identification of novel OHCA triggers is of crucial relevance. The aim of the study was to evaluate the association between air pollution (short-, mid- and long-term exposure) and out-of-hospital cardiac arrest (OHCA) risk, during a 7 years-period from a highly polluted urban area in northern of Italy, with a high density of automated external defibrillators (AEDs).<br /><b>Methods</b><br />OHCA were prospectively collected from the \"Progetto Vita Database\" between 01/01/2010 to 31/12/2017; day-by-day air pollution levels were extracted from the Environmental Protection Agency (ARPA) stations. Electrocardiograms of OHCA interventions were collected from the AEDs data cards. Day-by-day particulate matter (PM) 2.5 and 10, ozone (O3), carbon monoxide (CO) and nitrogen dioxide (NO2) levels were measured.<br /><b>Results</b><br />A total of 880 OHCAs occurred in 748 days. A significantly increased in OHCA risk with the progressive increase in PM 2.5, PM 10, CO and NO2 levels was found. After adjustment for temperature and seasons, a 9% and 12% increase of OHCA risk for each 10 μg/m3 increase of PM 10 (p < 0.0001) and PM 2.5 (p < 0.0001) levels was found. Air pollutants levels were associated with both asystole and shockable rhythm risk while no correlation was found with pulseless electrical activity.<br /><b>Conclusions</b><br />Short-term and mid-term exposure to PM 2.5 and PM 10 is independently associated with the risk of OHCA due to asystole or shockable rhythm.<br /><br />© The Author(s) 2023. Published by Oxford University Press on behalf of the European Society of Cardiology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.<br /><br /><small>Eur Heart J Acute Cardiovasc Care: 14 Sep 2023; epub ahead of print</small></div>