Effects of Angiotensin-Converting Enzyme Inhibitor Therapy on Clinical Outcome in Patients Undergoing Coronary Artery Bypass Grafting

Objectives: This study evaluates the effect of pre-operative angiotensin-converting enzyme inhibitor (ACEI) therapy on early clinical outcomes after coronary artery bypass grafting (CABG). Background: Therapy with ACEIs has been shown to reduce the rate of mortality and prevent cardiovascular events in patients with coronary artery disease. However, their pre-operative use in patients undergoing CABG is still controversial. Methods: A retrospective, observational, cohort study was undertaken of prospectively collected data on 10,023 consecutive patients undergoing isolated CABG between April 1996 and May 2008. Of these, 3052 patients receiving pre-operative ACEI were matched to a control group by propensity score analysis. Results: Overall rate of mortality was 1 %. Preoperative ACEI therapy was associated with a doubling in the risk of death (1.3 % vs. 0.7 %; odds ratio [OR]: 2.00, 95 % confidence interval [CI]: 1.17-3.42; p = 0.013). There was also a significant difference between the ACEI and control group in the risk of post-operative renal dysfunction (PRD) (7.1 % vs. 5.4 %; OR: 1.36, 95 % CI: 1.1-1.67; p = 0.006), atrial fibrillation (AF) (25 % vs. 20 %; OR: 1.34, 95 % CI: 1.18-1.51; p < 0.0001), and increased use of inotropic support (45.9 % vs. 41.1 %; OR: 1.22, 95 % CI: 1.1-1.36; p < 0.0001). In a multivariate analysis, pre-operative ACEI treatment was an independent predictor of mortality (p = 0.04), PRD (p = 0.0002), use of inotropic drugs (p < 0.0001), and AF (p < 0.0001). Conclusions: Pre-operative therapy with ACEI is associated with an increased risk of mortality, use of inotropic support, PRD, and new onset of post-operative AF.