Predictors of arrhythmia recurrence in patients with lone atrial fibrillation.

AIMS: The need for antiarrhythmic drugs (AAD) after a first episode of atrial fibrillation (AF) is determined by the probability of recurrence. The aim of this study was to asses the probability of relapse and the predictors of recurrence in patients with idiopathic AF. METHODS AND
RESULTS: A cohort of 98 consecutive patients younger than 65 years admitted at the emergency room because of an episode of symptomatic idiopathic (lone) AF was included in this study. On admission, a complete medical history was taken, and an echocardiogram and 24-h Holter monitoring were performed. Patients were seen at 3 and 6 months after the index episode. There were 35 (35.7%) patients with a new-onset AF episode and 63 (64.3%) with a recurrent AF episode. A majority of them were male (71%), with a mean age of 48+/-11 years. Patients with new-onset AF episodes did not receive AAD. At 6 month follow-up, 57% of all patients suffered at least one symptomatic AF relapse. Patients with AF relapses belong more often to the recurrent group vs. new-onset group of AF (65.1 vs. 34.9%, respectively, P = 0.03); they had larger LA diameter indexed for body surface area (BSA) (22.6+/-3.7 vs. 19.8+/-3.2 mm/m(2), P = 0.001), larger left ventricular end-systolic diameter (18.4+/-3.1 vs. 17.2+/-2.5 mm/m(2), P = 0.05) and a tendency towards a higher proportion of atrial tachycardia runs on Holter (66.7 vs. 50%, P = 0.09). Logistic regression analysis showed that the presence of previous episodes of AF (OR: 3.2; 95% CI; 1.0-8.0, P = 0.04) and a larger anteroposterior LA diameter (OR: 1.3; 95% CI; 1.1-1.6, P = 0.001) were independent predictors of AF recurrences at 6 months.
CONCLUSIONS: The recurrence rate in lone AF patients is high. The presence of previous episodes and a mildly enlarged anteroposterior LA diameter increase the probability of relapse of lone AF.