Amiodarone in the treatment of patients with refractory symptomatic ventricular and supraventricular arrhythmias. A long-term follow-up study.

Fifty-two patients with refractory symptomatic supraventricular and ventricular arrhythmias were treated with amiodarone (Cordarone-X; Reckitt & Colman) and followed up for a mean period of 36,4 months (range 3-54 months). Amiodarone was effective in controlling supraventricular arrhythmias in 18 of 22 patients (82%) and ventricular arrhythmias in 18 of 30 (60%), giving an overall success rate of 72%. The incidence of sudden death in the patients with ventricular arrhythmias was significantly higher (P less than 0,01) in patients whose symptoms were not controlled by amiodarone than in those in whom control was achieved. Although side-effects occurred in 50 of the 52 patients they seldom necessitated withdrawal of the drug. This is the first report in which a substantial number of patients have been closely followed up for a mean period exceeding 22 months. The results described here demonstrate that the potent antiarrhythmic properties of amiodarone, previously observed for shorter periods of time, are maintained for up to 4 1/2 years, and that there is neither an increased incidence nor progression of side-effects in patients exposed to the drug for these longer periods of time.