Utility of the CHADS-VASc Score in Prediction of Postoperative Atrial Fibrillation After Coronary Artery Bypass Graft Surgery.

OBJECTIVE

The authors aimed to investigate the role of CHADS-VASc score and its components in prediction of postoperative atrial fibrillation (POAF) after isolated coronary artery bypass graft (CABG) surgery.

DESIGN

Retrospective cohort.

SETTING

Single-center university-affiliated tertiary cardiac center.

PARTICIPANTS

A total of 2,981 consecutive patients who underwent isolated CABG between 2010 and 2012 were included.

INTERVENTIONS

All patients underwent isolated CABG and were followed until discharge or in-hospital death. The primary outcome was the development of new-onset POAF during the hospital course.

MEASUREMENTS AND MAIN RESULTS

During hospitalization, continuous electrocardiogram monitoring was used to detect POAF episodes. New-onset POAF developed in 15.8% of patients following isolated CABG. Patients with POAF had significantly higher CHADS-VASc scores than those without POAF (2.66 ± 1.51 v 2.12 ± 1.36, p < 0.001). After adjustment for potential confounders, CHADS-VASc score was significantly associated with POAF (odds ratio [OR]: 1.295, 95% CI: 1.205-1.391). However, further analyses showed that this effect was restricted to patients with a CHADS-VASc score of ≥2 (OR: 1.813, 95% CI: 1.220-2.694). In multivariate analysis of the CHADS-VASc components, age ≥75 (OR: 3.737, 95% CI: 2.702-5.168), age 65 to 74 (OR: 2.126, 1.701-2.658), hypertension (OR: 1.310, 95% CI: 1.051-1.633), and cerebrovascular accident (OR: 1.807, 95% CI: 1.197-2.726) were independent predictors of POAF. However, the association between POAF and female sex, diabetes mellitus, congestive heart failure, and vascular disease was not statistically significant.

CONCLUSIONS

CHADS-VASc score is a useful tool for the prediction of POAF after isolated CABG. However, the risk should be interpreted cautiously, since the risk score's promising effect relies on only several of its components.