Presentation, Treatment, and Outcome of Survivors of In-Hospital Versus Out-of-Hospital Sudden Cardiac Arrest

Abstract

We examined the baseline characteristics, rates of implantable cardioverter defibrillator implantation, and long-term all-cause mortality for survivors of in-hospital (IHSCA) versus out-of-hospital (OHSCA) sudden cardiac arrest (SCA). A total of 1,433 SCA survivors (807 IHSCA and 626 OHSCA) from 2002 to 2012 were followed through February 2017. Baseline characteristics and potential triggers of SCA, including significant electrolyte and metabolic abnormalities and acute myocardial infarction and ischemia, were collected. Adjusted survival analyses were performed using a multivariate Cox model. The presence of SCA triggers was similar between IHSCA and OHSCA patients (39% vs 35%, p = 0.3), but OHSCA was more likely associated with cardiac ischemia and drug abuse, whereas IHSCA was more associated with new antiarrhythmic drugs (p <0.05). OHSCA survivors were more likely to receive an implantable cardioverter defibrillator (38% vs 18%, p <0.001). Over a median follow-up of 3.6 years, 674 (47%) patients died. After adjusting for unbalanced baseline characteristics, survival was similar between IHSCA and OHSCA survivors (hazard ratio 1.1, 95% confidence interval 0.9 to 1.3, p = 0.4). In conclusion, survivors of IHSCA and OHSCA differed in baseline characteristic, potential SCA triggers, and treatment interventions but their adjusted survival was comparable.