Metabolic syndrome is associated with increased cardiac morbidity after infrainguinal bypass surgery irrespective of the use of cardiovascular risk-modifying agents

Background: The burden of metabolic syndrome (MetS) is increasing in the United States and is pervasive among patients with peripheral arterial disease. Whereas MetS has been implicated in the development of all types of cardiovascular disease and adverse outcomes after vascular interventions, little is known about how MetS influences perioperative outcomes of lower extremity bypass surgery and whether any negative effects can be modified by use of cardiovascular risk-modifying medications. Methods: We used the National Surgical Quality Improvement Program vascular procedure-targeted database to capture patients undergoing infrainguinal bypass surgery between 2011 and 2015. We defined MetS using the modified MetS criteria: concomitant diabetes, hypertension, and body mass index >30 kg/m ² . We used multivariable logistic regression analyses to examine the association between MetS and 30-day postoperative morbidity and mortality. We also examined whether preoperative aspirin, statin, and beta blockade modify the effects of MetS on 30-day postoperative outcomes. Results: Of 10,053 patients who underwent infrainguinal bypass, 16% (1693) met criteria for MetS. After adjusting for covariates, MetS was significantly (P ≤.05) associated with higher odds of postoperative myocardial infarction (odds ratio [OR], 1.66), infection (OR, 1.76), renal dysfunction (OR, 2.42), and length of stay (0.34 days). Within the MetS subgroup, there were no significant associations between use of preoperative cardiovascular risk-modifying agents and postoperative outcomes, with the exception of beta blockade and an increase in length of stay (0.33 days). Conclusions: Patients with MetS undergoing infrainguinal bypass surgery are at an increased risk of postoperative complications, including myocardial infarction. This elevated risk persists despite medical therapy with preoperative aspirin, statin, and beta blockade.