[Comparison of the efficacy of aprindine and quinidine in chronic ventricular rhythm disorders].

The object of this study was to compare the efficacity and the side effects of Aprindine and Quinidine in patients with stable ventricular arrhythmias. A series of 33 patients with chronic stable ventricular arrhythmias were given successively Aprindine and Quinidine on the principle of extrasystoles (VES) determined by computer analysis of Holter recordings. The VES were counted every hour and the statistical study used analysis of variance followed by linear contrast and also the sign test. The stability of the arrhythmia was verified by several control Holter recordings without therapy (average : 3,3 per patient). Low dose regimes were used in 17 patients (an average of 50 to 60mg/day Aprindine, and 481 mg Quinidine base), and Quinidine was shown to be the more active (p less than 0.05 to 0.003 according to the test used), reducing the number of VES by 39% compared to an average of 21% for Aprindine. In the other 16 patients with a higher dosage regime, 109 mg Aprindine and 707 mg Quinidine base, there was no significant difference between Quinidine and Aprindine (p less than 0.08 to 0.12), Quinidine reducing the number of VES by an average of 54%, and Aprindine by 36%. Quinidine caused diarrhoea in I patient on the low dose and 4 patients in the high dose regime. Aprindine caused neurological side effects in 2 patients on the low dose, and 7 patients on the high dose regime. Aprindine at 100 mg/day may therefore be used in the same manner as Quinidine at usual dosages as regards the incidence of side effects of the two drugs. However, the ratio of effective dose/toxic dose is lower with Aprindine than with Quinidine.