Impact of ECPELLA support on 30-day mortality and myocardial protection in patients with st-elevation myocardial infarction complicated by refractory cardiogenic shock requiring VA-ECMO before reperfu

Background Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is a critical form of mechanical circulatory support (MCS) for patients with refractory cardiogenic shock (CS). The combination therapy of VA-ECMO and Impella, known as ECPELLA, provides both systemic circulatory support and left ventricular (LV) unloading. However, whether the LV unloading effect of ECPELLA further reduces myocardial damage and mortality in Society for Cardiovascular Angiography and Interventions (SCAI) Stage E patients remains unclear. Objective To evaluate whether ECPELLA reduces myocardial damage and improves short-term survival in refractory CS patients with ST-elevation myocardial infarction (STEMI) requiring VA-ECMO before reperfusion. Methods Between January 2012 and January 2025, we retrospectively screened 239 acute coronary syndrome patients who required advanced mechanical circulatory support (MCS).Patients with non-STEMI, those who did not receive VA-ECMO during percutaneous coronary intervention (PCI) (n=81), and those with mechanical complications, such as left ventricular free wall rupture (n=8) or ventricular septal perforation (n=1), were excluded. Additionally, patients who had absent vital signs after MCS implantation and were deemed for withdrawal of care (n=7) were also excluded from the study. Ultimately, 77 consecutive STEMI patients who received VA-ECMO before reperfusion were included. Patients were divided into two groups: ECPELLA (n=48) and ECMO with IABP (n=28). Serum CK-MB levels and 30-day all-cause mortality were assessed. Results There were no significant differences between the groups in age, sex, coronary risk factors, left main trunk (LMT) lesion, or the rate of extracorporeal cardiopulmonary resuscitation (E-CPR). However, renal impairment (eGFR <60 mL/min/1.73 m²) was significantly more prevalent in the ECMO with IABP group. Additionally, the IABP-SHOCK II score, a prognostic score for CS, was significantly higher in the ECMO with IABP group than in the ECPELLA group (3 [3–4] vs. 4 [3–6]; p=0.015). The ECPELLA group had significantly higher MCS support flow per unit of body surface area during PCI and the first three days, received a significantly lower catecholamine dose, and demonstrated better lactate clearance. ECPELLA also resulted in significantly lower peak CK-MB levels (330 [115–562] IU/L vs. 500 IU/L; p=0.026). Kaplan-Meier analysis demonstrated a significantly higher 30-day survival rate in the ECPELLA group (p=0.003 by log-rank test). Multivariable Cox proportional hazard analysis, adjusting for age, E-CPR, LMT lesion, renal impairment, IABP-SHOCK II score, and ECPELLA, identified ECPELLA as the only independent factor associated with 30-day all-cause mortality (hazard ratio: 0.52, 95% confidence interval: 0.27–0.98; p=0.044). Conclusion ECPELLA treatment provides greater circulatory support and lower CK-MB levels, which may be associated with improved short-term survival compared to ECMO with IABP support.Figure1 Figure2