Predictors of atrial fibrillation recurrence in patients with long-lasting atrial fibrillation

Background Limited data are available on the predictors of atrial fibrillation (AF) recurrence in patients with chronic AF. Objectives To evaluate potential clinical, echocardiographic and electrophysiological predictors of AF recurrence after internal cardioversion for long-lasting AF. Methods A total of 99 consecutive patients (63 men and 36 women, mean age 63.33 ± 9.27 years) with long-standing AF (52.42±72.02 months) underwent internal cardioversion with a catheter that consisted of two defibrillating coils. Shocks were delivered according to a step-up protocol. Clinical follow-up and electrocardiographic recordings were performed on a monthly basis for a 12-month period or whenever patients experienced symptoms suggestive of recurrent AF. Results Ninety-three patients (93.94%) underwent a successful uncomplicated cardioversion, with a mean atrial defibrillation threshold of 10.69±6.76 J. Immediate reinitiation of AF was observed in 15 patients (15.78%) of whom a repeated cardioversion restored sinus rhythm in 13 cases. Early recurrence of AF (within one week) was observed in 12 of 93 patients (12.90%). At the end of the 12-month follow-up period, during which seven patients were lost, 42 of the 86 remaining patients (48.84%) were still in sinus rhythm. Multivariate regression analysis showed that left atrial diameter (OR 1.126, 95% CI 1.015 to 1.249; P = 0.025) and mitral A wave velocity (OR 0.972, 95% CI 0.945 to 0.999; P = 0.044) were significant and independent predictors of AF recurrence, whereas age, left ventricular ejection fraction and AF cycle length were not predictive of arrhythmia recurrence. Conclusion The present study showed that the left atrial diameter and mitral A wave velocity are the only variables associated with AF recurrence after successful cardioversion.