Early Left Ventricular Unloading after Venoarterial Extracorporeal Membrane Oxygenation: One-Year Outcomes of the EARLY-UNLOAD Randomized Clinical Trial

Background: The long-term effects of early left ventricular unloading after venoarterial extracorporeal membrane oxygenation (VA-ECMO) remain unclear.

Methods: The EARLY-UNLOAD trial was a single-center, investigator-initiated, open-label, randomized clinical trial involving 116 patients with cardiogenic shock (CS) undergoing VA-ECMO. The patients were randomly assigned to undergo either early routine left ventricular unloading by transseptal left atrial cannulation within 12 hours after randomization or the conventional approach, which permitted rescue transseptal cannulation in case of an increased left ventricular afterload. The prespecified secondary endpoints at 1 year included all-cause mortality, cardiac mortality, non-cardiac mortality, rehospitalization for heart failure, and the composite of all-cause mortality or rehospitalization for heart failure.

Results: At 1 year, data for 114 of 116 patients (98.3%) were available for analysis. All-cause death had occurred in 33 of 58 patients (56.9%) in early group and 32 of 56 patients (57.1%) in conventional group (HR, 0.97 [95% CI, 0.60 to 1.58], P=0.887). There was no significant difference in cardiac or non-cardiac mortality. Among 61 survivors at 30 days, the incidence of rehospitalization for heart failure at 1 year was comparable between 2 groups (HR, 1.17 [95% CI 0.43 to 3.24], P=0.758). The incidence of the composite outcome of all-cause mortality or rehospitalization for heart failure also did not differ between the groups (HR, 1.01 [95% CI 0.69 to 1.76], P=0.692).

Conclusions: Among patients with CS undergoing VA-ECMO, early routine left ventricular unloading did not improve clinical outcomes at 1-year of follow-up.

Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04775472.