Risk-adjusted outcome prediction with initial post-cardiac arrest illness severity: implications for cardiac arrest survivors being considered for early invasive strategy.

BACKGROUND

Early CATH is recommended for cardiac arrest survivors with STEMI or suspicion for coronary ischemia. Comatose patients are at risk of death from neurologic injury irrespective of CATH, but post-procedural mortality data do not distinguish between causes of death. Pittsburgh Post Cardiac Arrest Category (PCAC) is a validated, early post-cardiac arrest illness severity score based on initial cardiopulmonary dysfunction and neurologic examination. We evaluated the association between early coronary angiography (CATH) and patient outcome after adjusting for initial post-cardiac arrest illness severity.

METHODS

Retrospective study of a prospective cardiac arrest database at a single site. We included 1011 adult survivors of non-traumatic in-hospital or out-of-hospital cardiac arrest from 2005 to 2012, then stratified by PCAC and immediate CATH. Logistic regression tested the association between immediate CATH and patient outcomes, adjusting for PCAC.

RESULTS

Overall, 273 (27%) received immediate CATH. Patients with immediate CATH had higher proportions of good outcome in all but the most severe stratum of illness severity (11% vs. 6%; p=0.11). The primary mode of death was neurologic for all but the least severe stratum. Adjusting for PCAC, immediate CATH was associated with favorable discharge disposition (OR 1.92; 95%CI 1.20, 3.07; p=0.006) and modified Rankin scale (OR 1.95; 95%CI 1.12, 3.38; p=0.02).

CONCLUSIONS

The benefit of CATH is less clear in the most severe stratum of illness, in which the high risk of mortality is primarily from neurologic causes. PCAC is a risk-stratification tool that provides pre-procedural risk-adjusted outcome prediction for post-cardiac arrest patients being evaluated for immediate CATH.