Early left ventricular unloading after extracorporeal membrane oxygenation: rationale and design of EARLY-UNLOAD trial

Abstract

Aims: The clinical benefits of venoarterial extracorporeal membrane oxygenation (VA-ECMO) for profound cardiogenic shock are well known. However, peripheral VA-ECMO increases the left ventricular afterload, thus compromising myocardial recovery. Recent studies have revealed the benefit of left ventricular unloading using various methods applied at different times. The EARLY-UNLOAD trial compares the clinical outcomes of early left ventricular unloading and conventional approach after VA-ECMO.

Methods and results: The EARLY-UNLOAD trial is a single-centre, open-label, randomized trial that recruited 116 patients with cardiogenic shock undergoing VA-ECMO. Patients meeting the inclusion criteria were randomized in a 1:1 ratio to two groups: routine left ventricular unloading via intracardiac echocardiography-guided transseptal left atrial cannulation within 12 h of VA-ECMO initiation or conventional approach that indicates rescue left ventricular unloading if clinical signs of an increased left ventricular afterload are present. The primary endpoint is the cumulative incidence of all-cause death within 30 days, and patients will be followed-up for 12 months. A key secondary endpoint is a composite measure of all-cause death and rescue transseptal left atrial cannulation in the conventional group (suggestive of VA-ECMO treatment failure) within 30 days. The enrolment of patients was finished in September 2022.

Conclusions: The EARLY-UNLOAD trial is the first randomized controlled trial to compare early left ventricular unloading and conventional approach after VA-ECMO using the same unloading modality. The results could impact clinical practice to overcome the haemodynamic issues associated with VA-ECMO.

Keywords: Cardiogenic shock; Clinical trial; Extracorporeal life support; Extracorporeal membrane oxygenation; Left ventricular unloading.