Prompt Extracorporeal Cardiopulmonary Resuscitation with Left Ventricular Unloading by IMPELLA Improves Outcome of Patients with Refractory Cardiac Arrest: A Single-Site Retrospective Cohort Study

Abstract 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 significant effect on clinical outcome by concomitant use of VA-ECMO and IMPELLA (ECPELLA). In the current retrospective cohort study, we assessed factors affecting 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 the Cerebral Performance Categories (CPC). Results: There were no significant differences in age, gender, out of hospital CA, acute coronary syndrome among groups. The 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, P<0.0001) and ECPELLA (HR, 0.46, 95%CI, 0.24-0.88, P=0.02) were significantly associated with the clinical outcome. Conclusion: 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.