Progression From Paroxysmal to Sustained Atrial Fibrillation Is Associated With Increased Adverse Events

Background and Purpose- Atrial fibrillation (AF) is a common arrhythmic disorder among the elderly and sometimes progresses from paroxysmal to sustained (persistent or permanent) types. Clinical outcomes of patients with progression of AF were unknown. This study assessed the characteristics of patients with AF progression and the impact of AF progression on various clinical events. Methods- The Fushimi AF Registry is a community-based prospective survey of the patients with AF in Fushimi-ku, Kyoto. Analyses were performed on 4045 patients, which included 1974 paroxysmal AF (PAF; 48.8%) and 2071 sustained (persistent or permanent) AF (SAF; 51.2%) at baseline. Results- During the median follow-up period of 1105 days, progression of AF occurred in 252 patients with PAF (4.22 per 100 person-years). Multivariate Cox regression analysis demonstrated that progression of AF was significantly associated with an increased risk of ischemic stroke or systemic embolism (adjusted hazard ratio [HR], 4.10; 95% CI, 1.95-8.24; P<0.001 [versus PAF without progression]; adjusted HR, 2.20; 95% CI, 1.11-4.00; P=0.025 [versus SAF]) during progression period from paroxysmal to sustained forms. The risk after the progression was equivalent to SAF (adjusted HR, 1.54; 95% CI, 0.78-2.75; P=0.201 [versus SAF]). AF progression was significantly associated with a higher risk of hospitalization for heart failure (adjusted HR, 2.70; 95% CI, 1.55-4.52; P<0.001 [versus PAF without progression]; adjusted HR, 1.81; 95% CI, 1.08-2.88; P=0.026 [versus SAF]). Conclusions- Progression of AF was associated with increased risk of clinical adverse events during arrhythmia progression period from PAF to SAF among Japanese patients with AF. The risk of adverse events was transiently elevated during progression period from PAF to SAF and declined to the level equivalent to SAF after the progression. Clinical Trial Registration- URL: http://www.umin.ac.jp/ctr/ . Unique identifier: UMIN5834.