Features and Outcomes of Females and Males Requiring Postcardiotomy Extracorporeal Life Support.

Background: Although cardiogenic shock requiring extracorporeal life support (ECLS) after cardiac surgery is associated with high mortality, the impact of sex on outcomes of post-cardiotomy ECLS remains unclear with conflicting results in literature. We compare patient characteristics, in-hospital outcomes, and overall survival between females and males requiring post-cardiotomy ECLS. Methods: This retrospective, multicentre (34 centres), observational study included adults requiring post-cardiotomy ECLS between 2000 and 2020. Pre-operative, procedural, and ECLS characteristics, complications, and survival were compared between females and males. Association between sex and in-hospital survival was investigated through mixed-Cox proportional hazards models. Results: This analysis included 1823 patients [females:40.8%; median age:66.0 (interquartile range:56.2-73.0 years)]. Females underwent more mitral (females:38.4%, males:33.1%, p=0.019) and tricuspid (females:18%, males:12.4%, p<0.001) valve surgery, while males had more coronary artery surgery (females:45.9%, males:52.4%, p=0.007). ECLS implantation was more common intra-operatively in females (females:64.1%, males:59.1%) and post-operatively in males (females:35.9%, males:40.9%, p=0.036). Ventricular unloading (females:25.1%, males:36.2%, p<0.001) and intra-aortic balloon pump (females: 25.8%, males:36.8%, p<0.001) were most frequently used in males. Females suffered more post-operative right ventricular failure (females:24.1%, males:19.1%, p=0.016) and limb ischemia (females:12.3%, males:8.8%, p=0.23). In-hospital mortality was 64.9% in females and 61.9% in males (p=0.199) with no differences in 5-year survival (females:20%, 95%CI:17-23; males:24%, 95%CI:21-28;p=0.069). Crude hazard ratio for in-hospital mortality in females was 1.12 (95%CI: 0.99-1.27,p=0.069) and did not change after adjustments. Conclusions: This study demonstrates that females and males requiring post-cardiotomy ECLS have different pre-operative and ECLS characteristics, as well as complications, without a statistical difference in in-hospital and 5-year survival.