Abstract 233: The Relationship of Maximum Troponin Values Post Out-of-hospital Cardiac Arrest with Electrocardiographic Findings, Cardiac Procedures and Survival to Discharge; A Sub-study of ROC PRIMED

Abstract

Objective: To describe the relationship between maximum Troponin (Tn) levels recorded within 48 hours post arrest and clinical outcomes in out-of-hospital cardiac arrest (OHCA) patients enrolled in the Resuscitation Outcomes Consortium (ROC) Prehospital Resuscitation using an IMpedance valve and Early versus Delayed analysis (PRIMED) trial. Methods: A prospective observational cohort study of all treated non-traumatic OHCAs enrolled in ROC PRIMED. Patients were classified based on first presenting in-hospital ECG as ST elevation myocardial infarction (STEMI) or not a STEMI (including NSTEMI). Peak Tn levels, evaluated on a logarithmic scale, were compared across patient and treatment characteristics using a t-test or ANOVA. The association between categories of Tn levels (<0.1, 0.1-2, >2) and survival to discharge was evaluated using logistic regression adjusted for Utstein predictors of survival and ROC site. Results: Of the 15617 enrolled patients, 3661 (23%) survived at least 48 hours, 17% (693) were STEMI and 78% (3188) were not a STEMI with 5% unknown and 83% (3460) with at least one Tn level measured. The mean (SD) age was 64.6 (15.9). The STEMI group had more men (74.5% STEMI, 62% not a STEMI) and was more likely to have an initial shockable rhythm (73% STEMI, 39% not a STEMI). In-hospital survival was higher with STEMI (OR 1.93, 95% CI 1.63-2.3, p<0.001). The logarithm of Tn values was higher in STEMI patients (p <0.001). Adjusted in-hospital survival for STEMI patients was significantly better in those patients with higher Tn values (p=0.01). Adjusted in-hospital survival was significantly worse with higher Tn levels in the not a STEMI group (p<0.001). When treated with reperfusion, adjusted survival in the not a STEMI group was significantly better than the survival rate without reperfusion (OR 3.6, 95% CI 2.4-5.4 for trop>0.1, p<0.001). Conclusion: High Tn levels were associated with increased rates of reperfusion and better in-hospital survival in post-arrest patients with STEMI on first ECG. High Tn levels in not a STEMI patients post arrest were associated with decreased survival. Survival in not a STEMI patients was significantly higher when treated with reperfusion.