[Idiopathic atrial fibrillation: the course in paroxysmal and chronic forms]

Among 85 patients (including 16 women) with lone or idiopathic atrial fibrillation, 38 had a purely paroxysmal form while 47 showed chronic fibrillation, usually after a paroxysmal onset. Serious complications (congestive heart failure, syncope and embolic events) occurred in only two paroxysmal cases but in 11 chronic cases (rate of complications per year was 1.3% and 3.8% respectively). Thromboembolism was only observed after chronic fibrillation lasting longer than one year. Paroxysmal patients may be characterized by typical anamnestic features, namely short episodes of arrhythmia (usually less than 24 hours) and constant causative circumstances (mainly vagal stimulation). In these cases antiarrhythmic drugs are not usually recommended.