Predicting factors for long-term survival in patients with out-of-hospital cardiac arrest – A propensity score-matched analysis

BACKGROUND: Out-of-hospital cardiac arrest (OHCA) is one of the leading causes of death worldwide, with acute coronary syndromes accounting for most of the cases. While the benefit of early revascularization has been clearly demonstrated in patients with ST-segment-elevation myocardial infarction (STEMI), diagnostic pathways remain unclear in the absence of STEMI. We aimed to characterize OHCA patients presenting to 2 tertiary cardiology centers and identify predicting factors associated with survival. METHODS: We retrospectively analyzed 519 patients after OHCA from February 2003 to December 2017 at 2 centers in Munich, Germany. Patients undergoing immediate coronary angiography (CAG) were compared to those without. Multivariate regression analysis and inverse probability treatment weighting (IPTW) were performed to identify predictors for improved outcome in a matched population. RESULTS: Immediate CAG was performed in 385 (74.1%) patients after OHCA with presumed cardiac cause of arrest. As a result of multivariate analysis after propensity score matching, we found that immediate CAG, return of spontaneous circulation (ROSC) at admission, witnessed arrest and former smoking were associated with improved 30-days-survival [(OR, 0.46; 95% CI, 0.26–0.84), (OR, 0.21; 95% CI, 0.10–0.45), (OR, 0.50; 95% CI, 0.26–0.97), (OR, 0.43; 95% CI, 0.23–0.81)], and 1-year-survival [(OR, 0.39; 95% CI, 0.19–0.82), (OR, 0.29; 95% CI, 0.12–0.7), (OR, 0.43; 95% CI, 0.2–1.00), (OR, 0.3; 95% CI, 0.14–0.63)]. CONCLUSIONS: In our study, immediate CAG, ROSC at admission, witnessed arrest and former smoking were independent predictors of survival in cardiac arrest survivors. Improvement in prehospital management including bystander CPR and best practice post-resuscitation care with optimized triage of patients to an early invasive strategy may help ameliorate overall outcome of this critically-ill patient population.