Comparison of in‐hospital outcomes of patients with vs. without ischaemic cardiomyopathy undergoing veno‐arterial‐extracorporeal membrane oxygenation

AIMS: This study aimed to investigate differences in baseline and treatment characteristics, and in‐hospital mortality according to the aetiologies of cardiogenic shock in patients undergoing veno‐arterial‐extracorporeal membrane oxygenation (VA‐ECMO). METHODS AND RESULTS: The RESCUE registry is a multicentre, observational cohort that includes 1247 patients with cardiogenic shock from 12 centres. A total of 496 patients requiring VA‐ECMO were finally selected, and the study population was stratified by cardiogenic shock aetiology [ischaemic cardiomyopathy (ICM, n = 342) and non‐ICM (NICM, n = 154)]. The primary outcome of interest was in‐hospital mortality. Sensitivity analyses including propensity‐score matching adjustments were performed. Mean age of the entire population was 61.8 ± 14.2, and 30.8% were women. There were significant differences in baseline characteristics; notable differences included the older age of patients with ICM (65.1 ± 13.7 vs. 58.2 ± 13.8, P < 0.001), preponderance of males [258 (75.4%) vs. 85 (55.2%), P < 0.001], and higher prevalence of diabetes mellitus [140 (40.9%) vs. 39 (25.3%), P = 0.001] compared with patients in the NICM aetiology group. Patients with ischaemic cardiogenic shock were more likely to have longer shock duration before VA‐ECMO implantation (518.7 ± 941.4 min vs. 292.4 ± 707.8 min, P = 0.003) and were less likely to undergo distal limb perfusion than those with NICM [108 (31.6%) vs. 79 (51.3%), P < 0.001]. In‐hospital mortality in the overall cohort was 52.2%; patients with ICM had a higher unadjusted risk of in‐hospital mortality [203 (59.4%) vs. 56 (36.4%); unadjusted hazard ratio, 2.295; 95% confidence interval, 1.698–3.100; P < 0.001]. There were no significant differences in the primary outcome between the two aetiologies following propensity‐score matching multiple adjustments (adjusted hazard ratio, 1.265; 95% confidence interval, 0.840–1.906; P = 0.260). CONCLUSIONS: Results of the current study indicated among patients with cardiogenic shock undergoing VA‐ECMO, ischaemic aetiology does not seem to impact in‐hospital mortality. These findings underline that early initiation and appropriate treatment strategies of VA‐ECMO for patients with ICM shock are required.