Does advanced age affect the immediate and long-term results of direct-current external cardioversion of atrial fibrillation?

OBJECTIVES: To determine whether advanced age affects the immediate and long-term results of direct-current external cardioversion (ECV) of atrial fibrillation (AF), the sustained arrhythmia most commonly encountered in older patients. DESIGN: Retrospective analysis of medical records. SETTING: Intensive care unit. PARTICIPANTS: Two hundred fifty consecutive patients (age 34-100) with AF who underwent ECV following a standardized protocol in an intensive care unit. MEASUREMENTS: Immediate efficacy of ECV, defined as recovery of sinus rhythm, and maintenance of sinus rhythm over the follow-up were study outcomes. The univariate and multivariate associations of immediate efficacy of ECV and long-term results with clinical variables were analyzed. RESULTS: At univariate analysis, immediate efficacy of ECV (overall, 91.2%) was lower in older patients and in those with chronic obstructive pulmonary disease, higher for a 3- to 90-day pre-ECV duration of AF than for a duration of 2 days or less or more than 90 days, and independent of underlying cardiac disease, hypertension, diabetes mellitus, previous AF, and left atrial dimension. However, pre-ECV duration of AF was the only multivariate predictor of ECV immediate success. Major complications occurred in only three patients. Of 220 patients discharged in sinus rhythm, 211 were followed up for a mean period ± standard deviation of 34 ± 25 months. AF relapsed in 45.5% of them. At multivariate analysis, underlying cardiac disease was the only predictor of the relapse rate, and relapse rate was lower in coronary heart disease than in valvular heart disease, congestive heart failure, or lone AF. CONCLUSION: Immediate and long-term results of ECV of AF, an effective and safe procedure, are unaffected by age, at least after adjusting for several covariates.