Prediction of postoperative atrial fibrillation after coronary artery bypass grafting surgery: is CHA 2 DS 2 -VASc score useful?

AIMS AND OBJECTIVES: Postoperative atrial fibrillation (POAF) is the most common arrhythmia after coronary artery bypass grafting (CABG) surgery. The identification of patients at risk for POAF would be helpful to guide prophylactic therapy. Presently, there is no simple preoperative scoring system available to predict patients at higher risk of POAF. In a retrospective observational study, we evaluated the usefulness of CHA 2 DS 2 -VASc score to predict POAF after CABG.

MATERIALS AND METHODS: After obtaining approval from Institutional Review Board, 729 patients undergoing CABG on cardiopulmonary bypass (CPB) were enrolled. Patients were followed in the postoperative period for POAF. A multiple regression analysis was run to predict POAF from various variables. The area under the receiver operating characteristic (ROC) curve was calculated to test discriminatory power of CHA 2 DS 2 -VASc score to predict POAF.

RESULTS: POAF occurred in 95 (13%) patients. The patients with POAF had higher CHA 2 DS 2 -VASc scores than those without POAF (4.09 ± 0.90 vs. 2.31 ± 1.21; P < 0.001). The POAF rates after cardiac surgery increased with increasing CHA 2 DS 2 -VASc scores. The odds ratio for predicting POAF was highest with higher CHA 2 DS 2 -VASc scores (3.68). When ROC curve was calculated for the CHA 2 DS 2 -VASc scores, area of 0.87 was obtained, which was statistically significant (P < 0.0001).

CONCLUSIONS: The CHA 2 DS 2 -VASc score was found useful in predicting POAF after CABG. This scoring system is simple and convenient to use in the preoperative period to alert the clinician about higher probability of POAF after CABG surgery.