Progressive Nature of Paroxysmal Atrial Fibrillation-Observations From a 14-Year Follow-up Study-

Abstract

Atrial fibrillation (AF) is believed to occur first as paroxysmal, to be gradually perpetuated, and finally to develop into chronic as the end result. However, this presumed clinical course has not been well confirmed in a long-term perspective. The clinical courses of recurrent paroxysmal AF from its onset were examined in 171 patients (mean follow-up period 14.1±8.1 years). This study population consisted of patients with no structural heart disease (n=88), ischemic heart disease (n=28), dilated or hypertrophic cardiomyopathy (n=17), valvular heart disease (n=35) and others. The mean age at the onset of AF was 58.3±11.8 years old. During the mean follow-up period of 14.1 years, paroxysmal AF eventually developed into its chronic form in 132 patients under conventional antiarrhythmic therapy (77.2%, 5.5% of patients per year). The independent factors for early development into chronic AF were aging (hazard ratio [HR] 1.27 per 10 years, 95% confidence interval [CI] 1.06 to 1.47)), dilated left atrium (HR 1.39 per 10 mm, 95% CI 1.11 to 1.69), myocardial infarction (HR 2.33, 95% CI 1.13 to 4.81), and valvular diseases (HR 2.29, 95% CI 1.22 to 4.30). The present long-term observations definitely and quantitatively revealed the progressive nature of paroxysmal AF.