Abstract 55: VA ECMO for Cardiac Arrest and Severe Refractory Cardiogenic Shock

Abstract

Background: Critically ill cardiac patients, in cardiogenic shock or cardiac arrest, have worse outcomes than those who are less ill. Frequently, these patients require emergent initiation of veno-arterial extracorporeal membrane oxygenation (VA-ECMO) to sustain them until a LVAD can be placed. We report the profile and outcomes of patients supported with VA-ECMO. Methods: This is a retrospective cohort study of all adult patients who received mechanical circulatory support with VA-ECMO at the Hospital of the University of Pennsylvania from January 2010 to November 2011 for the indication of progressive severe refractory cardiogenic shock or cardiac arrest. Patients who were placed on ECMO post cardiac surgery were excluded from this study. Results: During the study period, 33 patients required VA ECMO, 15 for cardiac arrest and 18 for progressive severe refractory cardiogenic shock. The etiology of the acute heart failure included the following: coronary artery disease (48.5%), unstable arrhythmia (12.1%), post-procedural (15.2%), rejection (6%), and others (18.1%). The mean age was 50±13 year old, with 64% being male. The mean age of the patients who survived was 42±11 year old compared with 52 ±13 year old for non-survivors. The overall survival was 7/33 (21.2%). There was no difference in survival based on if the cause of the cardiac decompensation was cardiac arrest (survival rate: 20%) or progressive cardiogenic shock (survival rate: 22%). The survival in patients with ischemia was 6.25%, while survival in all other causes was 35.3% (p-value 0.041). The most common cause of death was refractory shock resulting in multisystem organ failure. Discussion: In this small cohort of critically ill patients, these findings are surprising and suggest that progressive cardiogenic shock has a prognosis that equates to cardiac arrest. A significant portion of cardiac arrest patients did not undergo hypothermia due to concern for excess hypercoagulability. The baseline coagulopathy is thought to be secondary to a DIC-like process brought on by blood interaction with the ECMO plastic tubing. Decision making regarding hypothermia is based on a patient’s underlying hypercoaguable state, which may lead to lack of neurologic protection.