Prospective comparative study of intravenous cibenzoline and disopyramide therapy in the treatment of paroxysmal atrial fibrillation after cardiovascular surgery.

BACKGROUND It has been reported that approximately one-third of patients undergoing cardiovascular surgery experience paroxysmal atrial fibrillation (AF) during the postoperative period. There is, however, little information on the selection of anti-arrhythmic drugs for terminating postoperative paroxysmal AF. METHODS AND RESULTS Between April 2007 and March 2009, 118 patients (76 men, 42 women, mean age 68+/-10 years) who had postoperative paroxysmal AF lasting > or =30 min were randomly assigned to receive either iv cibenzoline (70 mg, n=60) or disopyramide (50 mg, n=58) for terminating postoperative paroxysmal AF. The success rate of iv cibenzoline therapy (47%) was significantly greater than that of iv disopyramide therapy (24%; P<0.05). To identify clinical factors to increase the termination efficacy of iv cibenzoline, multivariate logistic regression was used to adjust for several covariates and to generate adjusted odds ratios (OR). The significant variables for the termination of paroxysmal AF after iv cibenzoline therapy were pretreatment with oral beta-adrenergic blockers (OR =8.224, P=0.030) and smaller left atrial dimensions (OR =0.879, P=0.039). CONCLUSIONS The efficacy of iv cibenzoline for the termination of postoperative paroxysmal AF was significantly better than that of disopyramide, especially in patients with pre-administration of oral beta-adrenergic blockers and those with smaller left atrium.