BACKGROUND: The prognostic impact of overweight and obesity in patients with cardiogenic shock (CS) following acute myocardial infarction (AMI) is still a matter of debate. The present subanalysis of the ECLS-SHOCK trial sought to investigate the association between body mass index (BMI) and outcomes in patients with AMI-CS.

METHODS: Patients with AMI-CS enrolled in the multicenter, randomized ECLS-SHOCK trial between 2019 and 2022 were included. The prognostic impact of BMI was investigated stratified by BMI 18.5-24.9 kg/m2, 25.0-29.9 kg/m2 and ≥ 30.0 kg/m2 with regard to the primary endpoint 30-day all-cause mortality.

RESULTS: Overall, 407 patients with AMI-CS were included with a median BMI of 27.7 kg/m2 (interquartile range 24.8-30.8 kg/m2). Patients with a BMI ≥ 30.0 kg/m2 (n = 115) were less likely males, had a higher burden of cardiovascular risk factors and higher rates of TIMI flow 0 before revascularization than patients with lower BMI values. The primary endpoint of all-cause mortality at 30 days occurred in 53.9%, 45.3% and 47.7% of patients with BMI ≥ 30.0 kg/m2, 25.0-29.9 kg/m2 and 18.5-24.9 kg/m2, respectively. Using patients with a BMI 18.5-24.9 kg/m2 as a reference, neither a BMI ≥ 30.0 kg/m2 (OR = 1.28; 95% CI 0.76-2.16; p = 0.35) nor a BMI of 25.0-29.9 kg/m2 (OR = 0.91; 95% CI 0.56-1.46; p = 0.68) were associated with an increased risk of all-cause mortality. Similar results were obtained regardless of allocation to extracorporeal life support (ECLS) or medical treatment only for all BMI groups. Safety endpoints did not differ across the different BMI groups.

CONCLUSION: In this well-defined cohort of patients with AMI-CS, BMI was not associated with the risk of all-cause mortality, nor were we able to identify BMI subgroups who derived more benefit or less harm from ECLS therapy.