Clinical predictors of atrial fibrillation recurrence in the Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto Miocardico-Atrial Fibrillation (GISSI-AF) trial

Background - Atrial fibrillation (AF) is a common arrhythmia that frequently recurs after restoration of sinus rhythm (SR). Identifying risk factors for recurrence may help define the best strategy for secondary prevention. Methods - The GISSI-AF trial enrolled 1,442 patients in SR with at least 2 documented AF episodes in the previous 6 months or after cardioversion in the last 2 weeks. Patients were randomized to valsartan or placebo; all other treatments for AF or underlying heart diseases were allowed. Primary end points were time to first recurrence of AF and proportion of patients with >1 AF episode during 1-year follow-up. We evaluated clinical and electrocardiographic baseline characteristics of all patients to identify independent predictors for AF recurrence using a Cox multivariable model. Results - Risk factors for AF recurrence were a history of 2 or more AF episodes in the previous 6 months, independent of the modality of SR restoration, spontaneous (HR 1.42, 95% CI 1.14-1.77, P = .002), or by cardioversion (HR 1.19, 95% CI 1.01-1.40, P = .038), and a lower heart rate during SR (HR 0.99, 95% CI 0.99-1.00, P = .052). The risk factors were the same for > 1 AF recurrence. Patients treated with amiodarone had a lower risk for both end points (P < .0001 and P = .017), whereas those on diuretics had a greater risk (P = .009 and P = .003). Conclusions - In the GISSI-AF study population, AF history had significant prognostic value independent of the modality of SR restoration. Amiodarone and diuretic treatment affected the rate of AF recurrence.