Preoperative angiotensin-blocking drug therapy is not associated with atrial fibrillation after cardiac surgery

Abstract

Background: Preoperative use of angiotensin-blocking drug therapy (ABDT) with angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers and its link to occurrence of postoperative atrial fibrillation (POAF), a common marker of poor outcomes after cardiac surgery, remain controversial.

Methods: From 1997 to 2003, 10,552 patients underwent coronary artery bypass grafting with or without valve surgery. To adjust for differences of clinical characteristics between patients who received ABDT within 24 hours before surgery compared with those who did not, propensity score analyses were conducted.

Results: Angiotensin-blocking drug therapy was prescribed in 4,795 (45%) before surgery, of which 1,725 (36%) developed POAF before discharge versus 1,908 (33%) of 5,757 patients who did not receive ABDT (unadjusted odds ratio 1.13, 95% CI 1.05-1.25, P < .01). In 6,744 propensity score-matched patients with well-balanced comorbidity profiles, ABDT was not associated with POAF (odds ratio 1.05, CI 0.95-1.16, P = .38). Stratified analysis within quintiles of propensity score and propensity-adjusted logistic multivariable regression confirmed these findings.

Conclusions: In this large observational study, we found no evidence of an association between preoperative angiotensin blockade and the occurrence of POAF. Adequately powered randomized studies are needed to clarify the best strategy of perioperative ABDT in patients with and without guideline-based indications.

Figure 1

Patient flow diagram AF indicates atrial fibrillation; CABG, coronary artery bypass grafting; ECG, electrocardiogram.

Figure 2

Density plot of propensity scores of patients with (dotted line) and without (solid line) Angiotensin blocking drug therapy. The overlapping area represents patients with similar propensity scores available for close matches.

Figure 3

Occurrence of postoperative atrial fibrillation by surgery type AVR indicates aortic valve replacement; CABG, coronary artery bypass grafting; Combined surgery, CABG with any combined valve surgery; MV, mitral valve; MVR, mitral valve replacement.

Figure 4

Standardized difference plot: Standardized differences in percent of patient characteristics between patients with and without preoperative Angiotensin blocking drug therapy before matching (dots) and after matching (squares). AV indicates Aortic Valve; BUN, blood urea nitrogen; ECG, electrocardiogram; LV, Left Ventricular; MI, myocardial infarction; MV, Mitral Valve; NYHA, New York Heart Association.

E-Figure 1