Effect of Propafenone on Chronic Ventricular Arrhythmias

We examined the efficacy of oral propafenone in patients with chronic ventricular arrhythmia by 24- hour Holter monitoring. Nine of the subjects were male and 10 female, with a mean age of 51 (ranging from 30 to 70). 13 of the cases had nonsustained ventricular tachycardia (VT), 6 had only ventricular premature beats (VPB). Propafenone therapy was started 450 mg/day. In nonresponders, the dosage was increased stepwise up to 900 mg/day, after ECG evaluation. Holter monitoring was repeated on the 15th day of treatment. The percentage of cases who responded to therapy well was 74, 7S, 92 and 79 in simple VPB, couplet, VT and total VPB groups, respectively. As a result, the mean reduction in simple VPBs, couplets, VTs and total VPBs were 73 %, S2 %, 99.9 %and 7S %, respectively (p<0.01). There were significant prolongations in P-R and QRS intervals during therapy (p<0.01) Cardiac complications (ventricular fibrillation, severe sinus arrest and nonsustained VT) were detected in 3 (16 %) and noncardiac complication (dizziness) in 2 (11 %) patients. We concluded that propafenone at a dose of 4S0-900 mg/day is an effective and tolerated antiarrhythmic drug in chronic ventricular arrhythmia cases. However, due to its potential risk of serious cardiac side effects, until results of more comprehensive investigations are available should be reserved for use in lifethreatening arrhythmias.