Prevalence of atrial fibrillation in patients with history of paroxysmal supraventricular tachycardia.

OBJECTIVES: This study was performed to evaluate the prevalence of atrial fibrillation (AF) in patients seen for paroxysmal supraventricular tachycardia (PSVT) and to identify factors favoring AF. AF incidence is increased in patients with PSVT, but AF risk factors are unknown. POPULATION: 1187 patients, mean age 50 ± 19 years, were consecutively studied for spontaneous PSVT confirmed by electrophysiological study (EPS). Patients with anterograde conduction through an accessory pathway were excluded.
METHODS: Clinical factors, age, gender, heart disease (HD) and electrophysiological data were noted. Patients with and without AF were compared. Mean follow-up was 4.48 ± 4.9 years.
RESULTS: 61 patients developed documented paroxysmal or permanent AF or atrial flutter (5%). They were older than patients without AF (59 vs 49 years, p<0.0005), were more frequently men (59% vs 37%) (p<0.002), had more frequently prior AF (24.5% vs 0.5%) (p<0.0001) and associated HD (18% vs 5%) (p<0.004). There were no differences at EPS concerning the mechanism of re-entry. AF induction or occurrence during EPS was more frequent in patients with AF (31%) than in patients without AF (9%) (p<0.001). Multivariate analysis showed age, male gender, prior AF, HD and atrial vulnerability during EPS were independent predictors of AF. Univariate comparison between both groups suggests no effect of PSVT ablation on the incidence of AF.
CONCLUSIONS: The prevalence of AF in our population was only 5%. The risk of AF was correlated with the classical risk factors of AF and atrial vulnerability during electrophysiological study. Patients with these risk factors should be followed.