Abstract Introduction Venoarterial extracorporeal membrane oxygenation (VA-ECMO) is used to restore systemic perfusion in cardiogenic shock (CS), but the retrograde aortic flow may increase left ventricular afterload and potentially impair myocardial recovery. The use of venting strategies may minimize this impact. Aim This study aims to assess if left ventricular unloading during VA-ECMO support is associated with lower mortality. Methods Single-center retrospective study including 107 consecutive patients with CS undergoing VA-ECMO from 2016 to 2025. Exclusion criteria was left ventricle ejection fraction (LVEF) 40%. A propensity score (PS) was used to match venting and no venting population in a 1:1 fashion according to age, sex, acute myocardial infarction (AMI) aetiology, LVEF, SCAI and cardiac arrest before VA-ECMO. Primary endpoint was 180-day mortality. Results The PS yielded two groups of 38 patients each mean age 51.5 (42.0-60.0) years, 80% (n=61) male, 37% (n=28) with AMI-CS, 51% (n=39) with previous cardiac arrest and 37% (n=28) in SCAI E, well matched for baseline characteristics. Among patients in the venting group, 87% (n=33) were unloaded with an intra-aortic balloon pump (IABP), 8% (n=3) with transseptal left atrial cannulation and 5% (n=2) with an Impella device. In the matched cohort, left ventricular unloading was associated with lower 30-day mortality (68.4% vs 36.8%, p=0.004) and 180-day mortality (76.3% vs 44.7%, p=0.002). In multivariate analyses, older age was significantly associated with a higher mortality risk (HR 1.046, 95% CI 1.00–1.09, p = 0.030), whereas venting was independently associated with improved survival (HR 0.18, 95% CI 0.06–0.56, p = 0.003). Although bacteraemia was more frequent in the venting group 11% (n=4) vs 40% (n=15), p=0.005), rates of clinically significant haemorrhage, pulmonary infection, and limb ischemia were similar between groups. Moreover, there were also no significant differences in the need for invasive mechanical ventilation or renal replacement therapy. Conclusion In this cohort of VA-ECMO patients with LVEF40%, left ventricular unloading, primarily with IABP support, was associated with lower 180-day mortality.
Sousa et al. (Fri,) studied this question.