Mortality Risk Among Patients Who Present to Hospitals with Out-Of-Hospital Cardiac Arrest and ST-Elevation Myocardial Infarction

Abstract

In the emergent setting of an ST-elevation myocardial infarction (STEMI) presenting with an out-of-hospital cardiac arrest (OHCA), decisions for immediate coronary angiography are made when the likelihood of survival is highly variable and unknown. A simple prognostic tool that can identify patients with a very high mortality risk upon hospital presentation may inform decision-making regarding emergent procedures. Within the Cardiac Arrest Registry to Enhance Survival (CARES), I included adult patients with OHCA and STEMI who presented from January 2013 to December 2019. Using multivariable logistic regression, I developed a predictive model and risk score for in-hospital mortality. Of 13,444 hospitalized patients with OHCA and STEMI (median age 64 [IQR 55-74], 31.6% female, 56.6% white), 8141 (60.6%) died. Higher age, non-shockable cardiac arrest rhythm, not having sustained return of spontaneous circulation upon hospital arrival, and total resuscitation time on scene were most predictive of mortality (C-statistic, 0.86). An integer risk score (range: 0-7) derived from this model estimated that patients with STEMI and OHCA has an in-hospital mortality from 15% to nearly 100%, with the odds of in-hospital mortality more than doubling for each additional point (odds ratio, 2.64; 95% CI, 2.55–2.73; p<0.001; C-statistic, 0.85). STEMI patients with OHCA have highly variable mortality risk. I created a simple prediction model comprised of four prehospital characteristics to estimate this risk. Further work is needed to define how this model can support procedural decision-making and better risk-adjustment for mortality-based quality measures in this high-risk population.