Risk of Adverse Events After Coronary Artery Bypass Graft and Subsequent Noncardiac Surgery

Abstract

Coronary artery bypass grafts (CABGs) are increasingly performed in elderly patients. Risk factors and outcomes are poorly described for those undergoing noncardiac surgery within 1 year after CABG. Our objectives were to assess the risk and predictors of major adverse events associated with noncardiac surgery within 1 year after CABG. In a retrospective review of medical records at Mayo Clinic (Rochester, MN, USA), over a period of 5 years, we identified patients who underwent noncardiac procedures within 1 year post-CABG. All events that occurred within 30 days after noncardiac surgery and deaths within 1 year after noncardiac surgery were considered to be related to CABG. We identified 211 patients; of these, 21 patients had 24 adverse events. Within 1 year, 11 died, and within the first 30 days, three myocardial infarctions, six acute congestive heart failure episodes, three cerebrovascular accidents and one deep vein thrombosis episode had occurred. Predictors of an adverse event included emergency operation (odds ratio: 6.8), ejection fraction less than 45% (p < 0.001) and elevated right ventricular systolic pressure by 40 mmHg or more (p = 0.03). After the noncardiac procedure, patients requiring dialysis (p = 0.02), ventilatory support (p = 0.03) and longer hospital stay (p = 0.03) had greater rates of adverse outcomes. Post-CABG, preoperative ejection fraction less than 45%, right ventricular systolic pressure of 40 mmHg or more, as well as emergent noncardiac surgery, were predictors of adverse outcomes after the noncardiac procedure. Longer postoperative hospital stay, dialysis, as well as ventilatory support, were predictors of adverse outcomes after CABG.