Effect and influencing factors of cardioversion on atrial fibrillation or atrial flutter in patients after cardiac valve surgery

Abstract

Objective To analyze the effect and influencing factor of cardioversion on atrial fibrillation or atrial flutter and the factors affecting the success of cardioversion in patients after heart valve surgery. Methods Ninety-one patients with atrial fibrillation or atrial flutter treated with cardioversion after heart valve surgery in Nanjing Gulou Hospital from January 2011 to June 2014 were retrospectively analyzed. Under intensive care unit (ICU) ECG monitoring, patients received synchronous cardioversion with bi-directional wave energy of 100 J -150 J after general anesthesia. Successful patients received oral amiodarone for 3 months. The immediate success rate of cardioversion and the sinus rhythm stability rate of follow-up for 1 to 6 months were counted. The patients were divided into two groups according to whether the cardioversion was successful or not: the successful cardioversion group and the unsuccessful cardioversion group, and the influencing factors that might affect the immediate success of cardioversion were analyzed. Results Among 91 patients, 39 were males and 52 were females, ranging in age from 26 to 76 years, with an average age of (54.3+ 11.1) years. Seventy-five patients (82.4%) immediately converted to sinus rhythm, and 64 patients (85.3%) maintained sinus rhythm after 1 to 6 months of follow-up. Low NYHA class, low BNP level, small left atrial diameter, atrial flutter and short duration of atrial fibrillation before surgery had higher success rate of cardioversion, but the operation method and the time distance between surgery and cardioversion had no significant effect on the success of cardioversion. Univariate and multivariate logistic regression analyses showed that left atrial diameter is an independent predictor of successful cardioversion. Conclusion Cardioversion is an effective method for patients with atrial fibrillation or flutter after cardiac valve surgery. Left atrial diameter before cardioversion is an independent predictor of successful cardioversion. Key words: Heart valvular disease; Atrial fibrillation; Atrial flutter; Cardioversion