Long-term survival in patients with acute myocardial infarction and out-of-hospital cardiac arrest: A prospective cohort study

Abstract

AimTo compare short- and long-term survival in patients admitted to hospital after acute myocardial infarction (AMI) with and without out-of-hospital cardiac arrest (OHCA). MethodsProspective cohort study of all AMI patients admitted to Oslo University Hospital Ulleval from September 1, 2005 to December 31, 2011. All-cause mortality was obtained from the Norwegian Cause of Death Registry with censoring date December 31, 2013. Cumulative survival was assessed with the Kaplan-Meier and the Life-table method. Logistic- and Cox regression were used for risk comparisons. ResultsWe identified 404 AMI patients with OHCA and 9425 AMI patients without. AMI patients without OHCA were categorized as ST-elevation myocardial infarction (STEMI, n=4522) or non-STEMI (NSTEMI, n=4903). Mean age was 63.6±standard deviation (SD) 12.5, 63.8±13.1 and 69.7±13.6 years in OHCA, STEMI and NSTEMI, respectively. Coronary angiography with subsequent percutaneous coronary intervention if indicated, was performed in 87% of OHCA, 97% of STEMI and 80% of NSTEMI patients. Thirty-day survival was 63%, 94% and 94%, and 8-year survival was 49%, 74%, and 57%, respectively. Among patients surviving the first 30days, no significant difference in risk during long-term follow-up was found (adjusted Hazard Ratio (aHR)OHCAvsSTEMI 1.15 [95% CI 0.82–1.60], aHROHCAvsNSTEMI 0.89 [95% CI 0.64-1.24]). ConclusionsLong-term survival after OHCA due to AMI was good, with 49% of admitted patients being alive after eight years. Although short-term mortality remained high, OHCA patients alive after 30days had similar long-term risk as AMI patients without OHCA.