Temporal Trends in VA-ECMO and Concurrent Mechanical Circulatory Support for Cardiogenic Shock

Abstract

Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is often combined with other temporary mechanical circulatory support (tMCS) in cardiogenic shock, yet combination-specific outcomes remain poorly defined. We compared temporal trends, mortality, complications, and device sequencing across VA-ECMO strategies. VA-ECMO patients in the Cardiogenic Shock Working Group registry were analyzed. Patients were grouped as VA-ECMO alone or by first overlapping device: Impella CP, Impella 5.5, or intra-aortic balloon pump (IABP). The primary outcome was in-hospital mortality. Multivariable logistic regression assessed associations with mortality. Of 11,386 cardiogenic shock patients, 1,502 (13.2%) received VA-ECMO, of whom 759 (50.5%) had concurrent tMCS [321 (21.4%) Impella CP, 208 (13.8%) Impella 5.5, and 230 (15.3%) IABP]. Concurrent Impella 5.5 was associated with lower mortality compared to VA-ECMO alone (aOR 0.62, 95% CI 0.45-0.86; P=0.004); no significant difference was observed for Impella CP or IABP. Overall mortality was 48.4%, higher with acute myocardial infarction (AMI) than heart failure shock (58.7% vs 40.9%; P<0.001). Across registry versions (2021-2025), isolated VA-ECMO use remained stable over time (45.0% to 48.9%; P for trend = 0.950), microaxial flow pump use increased (32.2% to 40.2%; P = 0.005), and IABP use declined (22.8% to 10.9%; P < 0.001). Anoxic brain injury was most strongly associated with mortality (aOR 10.51, 95% CI 6.26-17.64; P<0.001). More than half of VA-ECMO patients received a concurrent device, with increasing microaxial flow pump and declining IABP use. Complications and mortality differed across strategies and shock etiologies.