Background: The use of the CHA2DS2-VASc scoring system and red cell distribution width (RDW) as post-op Atrial Fibrillation (POAF) predictors may be promising for the identification of patients that are at a higher risk of POAF.
Methods: A total of 358 patients (57 patients with POAF, and 301 patients with non-POAF ) with sinus rhythm undergoing a coronary artery bypass graft (CABG) operation were included in the study retrospectively. Preoperative RDW levels and electrocardiograms with sinus rhythm were recorded. Patients with at least one 12-lead electrocardiogram with atrial fibrillation in the postoperative period, with or without medical or electrical cardioversion, were considered to have postoperative atrial fibrillation. A CHADS2 and CHA2DS2-VASc score was calculated for all of the patients.
Results: RDW levels were significantly higher in POAF group. RDW levels were significantly correlated with CHADS2 ( r = 0.15, P = .007) and CHA2DS2-VASc (r = 0.19 P = .0001) scores. CHA2DS2-VASc scores were significantly higher in patients with POAF, whereas CHADS2 scores did not differ between groups. In multivariate analysis, left atrial diameter (LAD) (OR:2.44 [95% CI 1.16 - 5.1], P = .018), age (OR:1.04 [95% CI 1.01 - 1.08], P = .01), and RDW (OR:1.16 [95% CI 1.0 - 1.36], P = .05) were found to be predictive for POAF. The area under the receiver-operating characteristic curve of RDW was 0.65 (0.57 - 0.72, P = .0001) with 68.4% sensitivity and 51.2 % specificity to predict POAF.
Conclusion: Our study showed that age, LAD, and the reduced probability of RDW are predictors of POAF, and that RDW is strongly associated with the thromboembolic risk as determined by CHADS2 and CHA2DS2-VASc scores.
Keywords: CABG, post-operative atrial fibrillation, red cell distribution width.