Evaluation of Time Course and Predicting Factors of Progression of Paroxysmal or Persistent Atrial Fibrillation to Permanent Atrial Fibrillation

BACKGROUND: To evaluate time course and predictors of progression of paroxysmal or persistent atrial fibrillation (AF) to permanent AF. METHODS AND RESULTS: We included 460 patients referred for paroxysmal (n = 337) or persistent (n = 123) AF between 1994 and 2012. Mean follow-up was 13.2 ± 6.5 years. AF progression rate was 3.7% per year, 19.7% at 5 years, and 38.1% at 10 years. Lone AF was diagnosed in 217 patients (47%). Predictors of permanent AF were: age, persistent AF, left atrial (LA) size, left ventricular-fractional shortening (LV-FS), lack of antiarrhythmic (AA) drugs, VVI pacing (P < 0.001 for all), and valvular disease (P < 0.02). Independent predictors were age (P < 0.001), persistent AF (P < 0.001), LA diameter (P < 0.005), lack of AA drugs (P < 0.005), and VVI pacing (P < 0.01). When adjusted at means of covariates, persistent AF and age >75 years remained highly significant (P < 0.01). LA dimension >50 mm was highly significant at univariate model (P < 0.001) but to a lesser extent when adjusted (P < 0.05). In patients with paroxysmal AF-with age <75 years-on AA drugs, progression rate to permanent AF was 6.5% at 5 years and 23.7% at 10 years. Among four predictors (age, LA size, LV-FS, and VVI pacing), only age (P < 0.01) and LA size (P < 0.005) remained independently significant, but LA size was not significant when adjusted. CONCLUSIONS: Progression to permanent AF is a slow process. Aging, LA size, VVI pacing, lack of AA therapy, and a persistent form of AF independently increased the progression to permanent AF.