[The efficacy of propafenone in preventing recurrent auricular fibrillation and flutter]

In order to investigate the efficacy of propafenone in the prevention of paroxysmal flutter or fibrillation, we treated 21 patients without left ventricular disfunction. Age was 60 +/- 14 (mean +/- sd) years, left atrial diameter by echocardiography 37 +/- 7 mm, cardiothoracic index 0.48 +/- 0.05 (0.41-0.57) and P wave duration 100 +/- 17 ms. The frequency of recurrences before treatment was: daily in five (23%), weekly or more in eight (38%), monthly-weekly in seven (33%) and quarterly-monthly in one (5%). Propafenone (671 +/- 187 mg/24 h) was given after recurrences were demonstrated under treatment with 1-3 antiarrhythmic drugs per patient. During 8.9 +/- 3.5 months of follow-up (range 6-19) 5 patients (23%) were completely free of recurrences; in seven (33%) the incidence decreased by greater than 50% with a marked decrease in duration. Side effects appeared in 12 cases (57%), leading to its discontinuation in four (19%). Arrhythmogenic effects were observed in 2 cases (9%). Propafenone is effective in greater than 50% of patients with paroxysmal atrial flutter or fibrillation, resistant to other antiarrhythmic agents. The incidence of side effects is high, but they are usually not severe and reversible.