Comparison of mechanical support with impella or extracorporeal life support in post-cardiac arrest cardiogenic shock: a propensity scoring matching analysis, on behalf of marpella investigators

Our aim was to compare the outcomes of Impella with extracorporeal life support (ECLS) in patients with post-cardiac arrest cardiogenic shock (CS) complicating acute myocardial infarction (AMI). This was a retrospective study of patients resuscitated from out of hospital cardiac arrest (OHCA) with post-cardiac arrest CS following AMI (May 2015 to May 2020). Patients were supported either with Impella 2.5/CP or ECLS. Outcomes were compared using propensity score-matched analysis to account for differences in baseline characteristics between groups. 159 patients were included (Impella, n = 105; ECLS, n = 54). Hospital and 12-month survival rates were comparable in the Impella and the ECLS groups (p = 0.16 and p = 0.3, respectively). After adjustment for baseline differences, both groups demonstrated comparable hospital and 12-month survival (p = 0.36 and p = 0.64, respectively). Impella patients had a significantly greater left ventricle ejection-fraction (LVEF) improvement at 96 h (p < 0.01 vs. p = 0.44 in ECLS) and significantly fewer device-associated complications than ECLS patients (15.2% versus 35.2%, p < 0.01 for relevant access site bleeding, 7.6% versus 20.4%, p = 0.04 for limb ischemia needing intervention). In subgroup analyses, Impella was associated with better survival in patients with lower-risk features (lactate < 8.6 mmol/L, time from collapse to return of spontaneous circulation < 28 min, vasoactive score < 46 and Horowitz index > 182). In conclusion, the use of Impella 2.5/CP or ECLS in post-cardiac arrest CS after AMI was associated with comparable adjusted hospital and 12-month survival. Impella patients had a greater LVEF improvement than ECLS patients. Device-related access-site complications occurred more frequently in patients with ECLS than Impella support.