Background: This study investigated the progression of paroxysmal atrial fibrillation (AF) to the persistent form in Japanese asymptomatic AF patients.
Methods and results: Data were derived from a single hospital-based cohort in the Shinken Database 2004-2012 (n=19,994), in which 1,176 patients were diagnosed as having paroxysmal AF. AF progression occurred in 115 patients (6.0%/year) during the mean follow-up period (1,213±905 days). Although patients who were asymptomatic at the initial visit (n=468) had a low-risk profile compared with symptomatic patients, they had greater AF progression at follow-up (unadjusted hazard ratio, 1.611; 95% CI: 1.087-2.389; P=0.018). Absence of symptoms, male sex, and cardiomyopathy were independent predictors for AF progression in the multivariate model. It was noted that asymptomatic patients were less likely to undergo pulmonary vein isolation (PVI). In addition, the interaction term between asymptomatic AF and absence of PVI could be another independent predictor for AF progression. Prognosis was similar between asymptomatic and symptomatic patients with AF.
Conclusions: Irrespective of low-risk profile, patients with asymptomatic paroxysmal AF had greater progression of AF compared with symptomatic patients. This paradoxical result appeared to be the result of less intensive clinical management, including invasive rhythm control.