539

Abstract

Introduction: Post-cardiac arrest myocardial dysfunction (MD) is a well recognized and common phenomenon. Understanding this phenomenon and its effect on neurologic outcome is important to the successful management of post-cardiac arrest patients. There are no clinical studies evaluating the effect of MD on outcome in post-cardiac arrest patients treated with Therapeutic Hypothermia (TH). Hypothesis: The objective of this study was to determine whether MD in post-cardiac arrest patients treated with TH is associated with worse neurologic outcome. MD is defined as global dysfunction on echocardiogram with ejection fraction (EF) < 30% within 48 hours of cardiac arrest. Methods: Review of consecutive post-cardiac arrest comatose adult patients treated with TH between May 2009 and December 2010. Demographic data, time to return of spontaneous circulation (ROSC), time to target temperature (TTT), echocardiogram findings, survival, and neurologic outcomes using cerebral performance category (CPC) scale at hospital discharge were prospectively recorded. Results: A total of 71 patients were enrolled. All patients received TH, with a target temperature of 33 oC for 24 hours. Patients with MD (n = 13) were matched with control group (EF > 30%, n = 58) on baseline characteristics, age (63 +/- 17 vs 62 +/- 15, in years), time to ROSC (18.2 vs 19.2, in minutes), and TTT (566+/-331 vs 502+/-268, in minutes) respectively. A CPC score of 1–2 represents a good outcome and a CPC score of 3–5, a bad outcome. 84.6 % (11/13) of MD patients had poor outcome versus 51.7 % (30/58) of control patients had poor outcome (p = 0.05). Myocardial dysfunction had an odds ratio for poor outcome of 5.1 (95% confidence interval, 1.1-25.1, p=0.05). Conclusions: Among a small number of post-cardiac arrest comatose adult patients treated with therapeutic hypothermia, patients who developed myocardial dysfunction (EF<30%) had worse outcomes compared with patients who had EF > 30%. This provides scientific rationale for large prospective clinical trials evaluating the effect of myocardial dysfunction on outcome in post-cardiac arrest comatose patients treated with therapeutic hypothermia.