Symptomatic Atrial Fibrillation Episodes Research Articles

Random and nonrandom behavior of symptomatic paroxysmal atrial fibrillation

Little is known about the behavior of symptomatic paroxysmal atrial fibrillation (AF). The nature of the process formed by the successive occurrences of this arrhythmia was studied in 8 patients with a history of symptomatic paroxysmal AF. Transtetephonic monitoring of the electrocardiogram was used to document the cardiac rhythm during symptoms. Patients were followed while successive attacks of paroxysmal AF were documented. A minimum of 12 and a maximum of 26 consecutive episodes of symptomatic paroxysmal AF were recorded from the 8 patients during 66 to 332 days. Methods developed in industrial reliability theory were used to show that, for the overall group of 8 patients, the interevent times between successive occurrences of symptomatic AF were not independent. However, for a subgroup including 6 of the patients, the interevent times were independent and governed by an exponential probability distribution. Differences in observed behavior of symptomatic AF may relate to differences in underlying mechanism within patients.

Long-term oral propafenone therapy for suppression of refractory symptomatic atrial fibrillation and atrial flutter

Sixty patients who had recurrent episodes of symptomatic atrial fibrillation or flutter, or both, and who had failed one to five prior drug trials were treated with open label oral propafenone hydrochloride. On a mean maximal tolerated dose of 795 ± 180 mg/day, actuarial estimates of the percent of individuals free of recurrences of symptomatic atrial fibrillation/flutter during propafenone treatment were: 1 month, 54%; 3 months, 44% and 6 months, 40%. No individual baseline characteristic achieved statistical significance as a correlate of poor response to propafenone. Drug-related adverse reactions were reported in 22% of patients but were severe enough to require termination of propafenone in only 5%.Thus, oral propafenone is a useful and well tolerated drug for long-term suppression of symptomatic recurrences of atrial fibrillation/flutter despite a history of unresponsiveness to prior antiarrhythmic drug treatment.

Electrophysiologic testing in the management of patients with the Wolff-Parkinson-White syndrome and atrial fibrillation

Twenty patients with the Wolff-Parkinson-White (WPW) syndrome and 1 or more episodes of symptomatic atrial fibrillation (AF) due to rapid anterograde bypass tract conduction underwent electrophysiologic testing. The mean ventricular rate during spontaneous AF was 242 ± 56 beats/min (± standard deviation) and the shortest preexcited R-R interval was 194 ± 40 ms. Six patients underwent surgical bypass tract ablation and 14 were treated medically, based on the results of electropharmacologic testing. Over a mean follow-up period of 35 ± 19 months (± standard deviation), only 1 patient treated medically had a recurrence of minimally symptomatic AF. The successful chemoprophylaxis of symptomatic AF was associated with the inability to induce AF and atrioventricular reciprocating tachycardia during drug testing (7 patients) or with the induction of AF with a ventricular rate < 200 beats/min and a shortest preexcited R-R interval of > 250 ms (7 patients). Electrophysiologic testing can identify a subgroup of patients with WPW and AF in whom medical therapy is a suitable alternative to bypass tract ablation.