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.