Effect of angiotensin-converting enzyme inhibitors and angiotensin receptor blockers on risk of atrial fibrillation before coronary artery bypass grafting.

OBJECTIVE: To review the primary literature evaluating the effect preoperative use of angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) has on the risk of postoperative atrial fibrillation following coronary artery bypass grafting (CABG).

DATA SOURCES: PubMed was searched from January 1, 2000, to May 17, 2012, using the MeSH terms coronary artery bypass, angiotensin-converting enzyme inhibitors, angiotensin receptor antagonists, and atrial fibrillation. Additional articles were identified from the reference lists of the articles identified in the PubMed search.

STUDY SELECTION AND DATA EXTRACTION: Abstracts from the PubMed search were screened for relevance to the topic. Articles including information on the effect of ACE inhibitors or ARBs on postoperative atrial fibrillation following CABG were indentified for further review. Data extracted from these studies included patient baseline characteristics, outcome definitions, incidence of atrial fibrillation after CABG, and preoperative use of ACE inhibitors or ARBs.

DATA SYNTHESIS: The PubMed search resulted in 6 articles, 4 of which were applicable to the clinical question. Four other articles were identified from the reference lists of the applicable studies, resulting in a literature review of 8 studies. These studies included patients undergoing CABG with or without valve procedures. Four studies included patients undergoing isolated CABG procedures; the remaining 4 included patients undergoing CABG with a valve procedure. Information on preoperative ACE inhibitor or ARB use was included in all studies. Two studies suggested a decreased risk of postoperative atrial fibrillation following CABG with preoperative ACE inhibitor or ARB therapy, 3 suggested an increased risk, and 3 found no effect on risk.

CONCLUSIONS: The studies reviewed here had conflicting results. Randomized placebo-controlled trials are necessary to determine the risk for atrial fibrillation after CABG associated with preoperative use of ACE inhibitors and ARBs. The decision to continue or withhold the drugs is not evidence-based and should be based on a patient's other clinical characteristics.