CLINICAL-EVALUATION AND MEDIUM-TERM PROGN OSIS OF IDIOPATHIC ATRIAL-FIBRILLATION

Forty-six patients with idiopathic or lone atrial fibrillation (AF) un derwent clinical evaluation in the cardiology outpatient department. T he follow-up period was 4.6 +/- 2.5 years. The prevalence of idiopathi c AF was 19 % (89 % paroxysmal and 11 % permanent) in a population of 244 patients with atrial fibrillation. The global prevalence was 1.15 % out of 4 000 patients examined over the same period. A history of pa roxysmal atrial fibrillation over a 6 +/- 4 year period was obtained i n 61 % of the patients with idiopathic AF before the study. At inclusi on, 24 % of patients were asymptomatic. During follow-up, 12 patients (26 %) developed cardiovascular disease and/or hypertension. The size of the left atrium was measured by echocardiography in 45 patients and reevaluated in 30 of them during follow-up without any statistically significant difference being observed between the two values. There we re no thromboembolic complications or deaths during follow-up. These r esults show that idiopathic AF is not uncommon in cardiology clinics. The evolution of the paroxysmal forms is variable-but the medium-term prognosis is excellent. In some cases, idiopathic AF may be a manifest ation of asymptomatic coronary artery disease but the relationship bet ween the two pathologies has not been definitely established.