PROPAFENONE VERSUS PROPRANOLOL IN PREVENTION OF RECURRENCES OF PAROXYSMAL ATRIAL-FIBRILLATION

The aim of the present study was to compare the efficacy of propranolo l and propafenone in prevention of recurrences of paroxysmal atrial fi brillation (PAF). The study group consisted of 58 patients with sympto matic attacks of PAF who were randomly assigned to propranolol (Propra nolol, Polfa) (target dose -120 mg/day) or propafenone (Rytmonorm, Kne ll) (450 mg/day, if ineffective -600 mg/day). Patients who had a recur rence of PAF while taking one drug, received the other drug tested in the study. Patients had been followed in the outpatient clinic for 6 m onths. The endpoints of the study were symptomatic recurrence of PAF o r intolerable side effects which caused discontinuation of treatment. As the first therapy, propranolol was effective in 13 (45%) of 29 pati ents whereas propafenone -in 16 (55%) of 29 patients (NS). Of 11 patie nts who had recurrence of PAF while on propafenone, propranolol was ef fective in one patient (9%) compared to 7 (47%) of 15 patients who rec eived propafenone as a second drug because of ineffectiveness of propr anolol (p = 0.04). In total, there were 84 antiarrhythmic drug trials in 58 patients: 40 propranolol trials and 44 propafenone trials. Propr anolol was effective in 14 (35%) patients whereas propafenone -in 23 ( 53%) patients (NS). Serious adverse events caused discontinuation of t herapy in 3 patients treated with propranolol and in 6 patients treate d with propafenone (NS). Serious proarrhythmic effects (conversion of well tolerated PAF into haemodynamically unstable paroxysmal atrial fl utter) were noted only in 3 patients who received propafenone. In summ ary: (1) propafenone tends to be superior to propranolol in prevention of recurrences of PAF; (2) propafenone is effective in a significant proportion of patients with PAF who failed to respond to propranolol, and (3) serious adverse events are more frequent during propafenone th an propranolol treatment.