Early left atrial venting versus conventional treatment for left ventricular decompression during venoarterial extracorporeal membrane oxygenation support: The EVOLVE‐ECMO randomized clinical trial

Abstract

AimsFew studies have reported data on the optimal timing of left ventricular (LV) unloading during venoarterial extracorporeal membrane oxygenation (VA‐ECMO) for cardiac arrest or shock. This study evaluated the feasibility of an early LV unloading strategy compared with a conventional strategy in VA‐ECMO.Methods and resultsBetween December 2018 and August 2022, 60 patients at two institutions were randomized in a 1:1 ratio to receive early (n = 30) or conventional (n = 30) LV unloading strategies. The early LV unloading strategy was defined as LV unloading performed at the time of VA‐ECMO insertion. LV unloading was performed using a percutaneous transseptal left atrial cannulation via the femoral vein incorporated into the ECMO venous circuit. The early and conventional LV unloading groups included 29 (96.7%) and 23 (76.7%) patients, respectively (median time from VA‐ECMO insertion to LV unloading: 48.4 h, interquartile range 47.8–96.5 h). The groups showed no significant differences in the rate of VA‐ECMO weaning as the primary endpoint (70.0% vs. 76.7%; relative risk 0.91; 95% confidence interval 0.67–1.24; p = 0.386) and survival to discharge (53.3% vs. 50.0%, p = 0.796). However, the pulmonary congestion score index at 48 h after LV unloading was significantly improved only in the early LV unloading group (2.0 ± 0.7 vs. 1.7 ± 0.6 at baseline vs. at 48 h; p = 0.008).ConclusionsCompared with the conventional approach, early LV unloading did not improve the VA‐ECMO weaning rate, despite the rapid improvement in pulmonary congestion. Therefore, the results of this study do not support the application of this strategy after VA‐ECMO insertion.

Watchful waiting for venting in venoarterial extracorporeal membrane oxygenation

“…With their study findings, Park et al 9 . lead us one step further in our quest to understand the complex haemodynamic interplay between the failing heart and the VA‐ECMO circuit.…”

“…In this issue of the Journal, Park et al 9 . presents the first prospective, randomized, open‐labelled, multicentre, superiority trial (EVOLVE‐ECMO), comparing a strategy of concomitant LV unloading at the time of VA‐ECMO insertion (early) versus LV unloading post VA‐ECMO insertion at the time of medically refractory pulmonary oedema (conventional) on the rate of weaning from VA‐ECMO.…”

“…With their study findings, Park et al 9 lead us one step further in our quest to understand the complex haemodynamic interplay between the failing heart and the VA-ECMO circuit. However, larger-scale randomized controlled trials are essential to establish the optimal timing and indication for LV unloading during VA-ECMO.…”

“…5 Although previous work has shown favourable outcomes of LV unloading during VA-ECMO therapy, 6 there is no consensus on the indication and timing of LV unloading in the setting of VA-ECMO treatment. In fact, the available evidence is contradictory and is mainly based on few observational or retrospective studies, 7,8 and to date there exists no well-controlled randomized trial In this issue of the Journal, Park et al 9 presents the first prospective, randomized, open-labelled, multicentre, superiority trial (EVOLVE-ECMO), comparing a strategy of concomitant LV unloading at the time of VA-ECMO insertion (early) versus LV unloading post VA-ECMO insertion at the time of medically refractory pulmonary oedema (conventional) on the rate of weaning from VA-ECMO. Secondary endpoints included the rate of survival to discharge, successful HTx, or LVAD implantation, the duration of mechanical ventilation (MV), improvement of pulmonary oedema, and any adverse events related to VA-ECMO.…”

November 2023 at a glance: Focus on cardiogenic shock, post‐discharge outcomes and cardiomyopathies

“…The early strategy did not improve the VA-ECMO weaning rate, despite the more rapid improvement in pulmonary congestion. 29 cardiomyopathy, or early dilated cardiomyopathy. Myocardial fibrosis was present in 65 of the 256 patients (26%).…”