The use of inhibitors of angiotensin-converting enzyme and its relation to events in the postoperative period of CABG

Background: Angiotensin-converting enzyme (ACE) inhibitors reduce the chance of death, myocardial infarction (MI) and cerebrovascular accident (CVA) in patients with coronary disease. However there is no consensus as to its indication in patients undergoing coronary artery bypass grafting (CABG). Objective: To assess the relationship between preoperative use of ACE inhibitors and clinical outcomes after CABG. Methods: Retrospective cohort study. We included data from 3,139 consecutive patients undergoing isolated CABG in Brazilian tertiary care hospital between January 1996 and December 2009. Follow-up was until discharge or death. Clinical outcomes after surgery were analyzed between users and nonusers of ACE inhibitors preoperatively. Results: Fifty-two percent (n=1,635) of patients received ACE inhibitors preoperatively. The use of ACE inhibitors was an independent predictor of need for inotropic support (OR 1.24, 95% CI 1.01 to 1.47, P= 0.01), acute renal failure (OR 1.23, 95% CI 1.01 to 1.73, P = 0.04) and progression to atrial fibrillation (OR 1.32, 95% Cl 1.02 to 1.7, P = 0.03) postoperatively. The mortality rate among patients receiving or not preoperative ACE inhibitors was similar (10.3% vs. 9.4%, P = 0.436), as well as the incidence of myocardial infarction and stroke (15.6% vs. 15.0%, P= 0.694 and 3.4% vs. 3.5%, P= 0.963, respectively). Conclusion: The use of preoperative ACE inhibitors was associated with increased need for inotropic support and higher incidence of acute renal failure and postoperative atrial fibrillation, not associated with increased rates of myocardial infarction, stroke or death.