Prompt extracorporeal cardiopulmonary resuscitation with left ventricular unloading by IMPELLA improves the outcome of patients with refractory cardiac arrest: A single-site retrospective cohort study

Background: Extracorporeal cardiopulmonary resuscitation (E-CPR) using venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a novel lifesaving method for refractory cardiac arrest (CA). However, VA-ECMO increases damaged left ventricular (LV) afterload. The percutaneous microaxial pump Impella can reduce LV preload with simultaneous circulatory support, which may have a significant effect on clinical outcome by concomitant use of VA-ECMO and IMPELLA (ECPELLA). In the current retrospective cohort study, we assessed factors affecting the outcome of CA patients who underwent E-CPR.Method: We retrospectively reviewed 149 consecutive CA patients with E-CPR from January 2012 through December 2020 in our institute. Patients were divided into three groups: ECEPLLA (n=29), IABP + VA-ECMO (n=78), and single VA-ECMO (n=42). We assessed 30-day survival and neurological outcome using cerebral performance categories (CPCs).Results: There were no significant differences in age, sex, out-of-hospital CA, or acute coronary syndrome among the groups. ECPELLA showed the highest cumulative 30-day survival (ECPELLA: 55%, IABP + VA-ECMO: 23%, VA-ECMO: 9.5; p=0.001) and the rates of CPC score 1 or 2 (ECPELLA: 31%, IABP + VA-ECMO: 13%, VA-ECMO: 7%; p=0.02). Multivariate analysis revealed that age (hazard ratio [HR], 1.30, 95% confidence interval [CI], 1.13-1.52, P=0.005) and time from CA to ECMO support (HR, 1.22, 95% CI, 1.13-1.31, PConclusion: Earlier initiation of E-CPR is critical to improve patient survival and neurological outcome. Additional Impella support, ECPELLA, appears to significantly improve the clinical outcome.