[The immediate and long-term efficacy of electrical cardioversion in atrial fibrillation].

With the aim to identify short- and long-term features predictive of successful electric cardioversion in stable atrial fibrillation, 186 consecutive patients submitted to electric cardioversion were reviewed. The following parameters were considered: age, atrial fibrillation duration, previous atrial fibrillation episodes, echocardiographic left atrial diameter, pre-treatment and prophylaxis with amiodarone. The patients were divided in 3 groups: Group I included 97 patients with mitral valve disease or mitral prosthesis, Group II included 27 patients with lone atrial fibrillation and Group III included 62 patients with different heart and extracardiac diseases. The electric cardioversion restored sinus rhythm in 155 patients (83%). The failure of the electric cardioversion was related only to a longer atrial fibrillation duration and to pre-treatment with amiodarone. Moreover, the failure of the electric cardioversion was more frequent in Group II patients (with lone atrial fibrillation) than in Group I patients (mitral disease or prosthesis; p < 0.005). Only for Group I patients failure of the cardioversion was related to a larger left atrium diameter (p < 0.05). Eighty-nine (57%) of the 155 patients converted to sinus rhythm were followed for at least 1 year. At 1 year sinus rhythm persisted in 57 patients (64%), and prophylaxis with amiodarone was the only predictor of sinus rhythm persistence (p < 0.05). Out of 68 patients with a 3 year follow-up, 29% still showed sinus rhythm after a single cardioversion and 37% after 2 or more cardioversions; after 5 years, out of 58 patients, those showing sinus rhythm were 6 (10.3%) and 9 (16%) respectively.(ABSTRACT TRUNCATED AT 250 WORDS)