Contemporary Outcomes of Temporary Mechanical Circulatory Support Use in Ischemic Ventricular Septal Defect: A US Multicenter Analysis.

Abstract

Ischemic ventricular septal defect (VSD) remains a lethal complication of acute myocardial infarction, often requiring temporary mechanical circulatory support (tMCS) to stabilize hemodynamics. This study aimed to characterize contemporary use and outcomes of tMCS in ischemic VSD across US transplant centers. Retrospective data from 7 centers (2014-2023) were analyzed, including 117 patients with ischemic VSD. Sixty patients received extracorporeal membrane oxygenation (ECMO group) and 57 did not (No-ECMO group). Clinical characteristics, intervention types, and outcomes were compared. The mean annual case per center ranged from 1 to 2.5 per year. Overall, 89.7% of patients required tMCS, most commonly intraaortic balloon pump (62.4%). Venoarterial ECMO was used in 51.3%, often combined with intraaortic balloon pump or Impella (Abiomed). The ECMO group exhibited greater preoperative acuity, with higher lactate, creatinine, and transaminases, and worse ventricular function. Mortality before any intervention was significantly higher with ECMO (30.0% vs 1.8%, P < .001). Among those undergoing intervention, hospital mortality was 52.4% in the ECMO group and 28.6% without ECMO (P < .001). Seven patients received advanced therapy (concomitant durable left ventricular assist device and VSD repair, n = 3; reoperative left ventricular assist device after VSD repair, n = 3; and heart transplant, n = 1) with mortality of 28.6%. Multivariable analysis identified requirement of ECMO support, lactate ≥3 mmol/L, and left ventricular ejection fraction <50% as independent predictors of mortality. Ischemic VSD often necessitates tMCS, with venoarterial ECMO support in nearly half of cases. Although the outcomes remain guarded, advancements in tMCS technology, patient selection, and comprehensive approach are crucial in this challenging population.