Association of Metabolic Surgery With Major Adverse Cardiovascular Outcomes in Patients With Previous Myocardial Infarction and Severe Obesity: A Nationwide Cohort Study

Abstract

Background: The number of patients with myocardial infarction and severe obesity is increasing and there is a lack of evidence how these patients should be treated. The aim of this study was to investigate the association between metabolic surgery (Roux-en-Y gastric bypass and sleeve gastrectomy) and major adverse cardiovascular events in patients with previous myocardial infarction (MI) and severe obesity.

Methods: Of 566 patients with previous MI registered in the SWEDEHEART registry (Swedish Web-System for Enhancement and Development of Evidence-Based Care in Heart Disease Evaluated According to Recommended Therapies) undergoing metabolic surgery and registered in the nationwide Scandinavian Obesity Surgery Registry, 509 patients (Roux-en-Y gastric bypass n=465; sleeve gastrectomy n=44) could be matched 1:1 to a control with MI from SWEDEHEART, but no subsequent metabolic surgery regarding sex, age (±3 years), year of MI (±3 years), and body mass index (±3). The 2 groups were well matched, except for a lower proportion of reduced ejection fraction after MI (7% versus 12%), previous heart failure (10% versus 19%), atrial fibrillation (6% versus 10%), and chronic obstructive pulmonary disease (4% versus 7%) in patients undergoing metabolic surgery.

Results: The median (interquartile range) follow-up time was 4.6 (2.7-7.1) years. The 8-year cumulative probability of major adverse cardiovascular events was lower in patients undergoing metabolic surgery (18.7% [95% CI, 15.9-21.5%] versus 36.2% [33.2-39.3%], adjusted hazard ratio, 0.44 [95% CI, 0.32-0.61]). Patients undergoing metabolic surgery had also a lower risk of death (adjusted HR, 0.45 [95% CI, 0.29-0.70]; MI, 0.24 [0.14-0.41]) and new onset heart failure, but there were no significant differences regarding stroke (0.91 [0.38-2.20]) and new onset atrial fibrillation (0.56 [0.31-1.01]).

Conclusions: In severely obese patients with previous MI, metabolic surgery is associated with a low risk for serious complications, lower risk of major adverse cardiovascular events, death, new MI, and new onset heart failure. These findings need to be confirmed in a randomized, controlled trial.

Keywords: bariatric surgery; myocardial infarction; obesity; secondary prevention.