[Clinical study of the effectiveness of mexitil in the treatment of patients with extrasystole in old and advanced age]. / Klinische Untersuchung über die Effektivität von Mexitil bei der Behandlung von Patienten mit Extrasystolen höheren und hohen Lebensalters.

The antiarrhythmic efficacy and action of mexitil on minute volume, myocardial function and vegetative regulation of cardiac activity were studied in 25 patients aged 60-89 years, suffering from chronic IHD with stable ventricular extrasystoles. With mexitil dosage of 400-600 mg orally per day there was a marked antiarrhythmic effect in 68% of patients. A similar effect in 64% of patients was observed with a single dose of mexitil (300 mg orally per day) as early as 1-2 h after its administration and maintained for 8-10 h. The above dose of mexitil produced a statistically significant slowing down of cardiac rhythm without changing atrioventricular conductivity. No effect of mexitil on arterial blood pressure was found, nor did it exert cardiodepressive action or any purposeful effect on the vegetative regulation of the heart.

[Effectiveness and characteristics of the action of etmozin in treating extrasystole in middle-aged and elderly patients]. / Effektivnost' i osobennosti deistviia étmozina pri lechenii ékstrasistolii u bol'nykh pozhilogo i starcheskogo vozrasta.

Antiarrhythmic efficiency and specific effects of ethmozine, taken alone in increasing oral doses from 300 to 450 mg daily, were evaluated in 48 elderly and old coronary patients with stable supraventricular and ventricular extrasystoles (SVES, VES). It was demonstrated clinically and instrumentally (ECG, rhythmography, bicycle ergometry with standard exercise, cardiac rhythm monitoring and computer analysis, polycardiography, tetrapolar chest rheography) that ethmozine's antiarrhythmic effect was marked (a more than 75% post-treatment decline in the frequency of extrasystoles at rest and during exercise, provided that paired polytopic extrasystoles and paroxysms of tachycardia are suppressed completely) in 52.1% of SVES patients and 60% of VES patients. Antiarrhythmic action of a 300 mg ethmozine load dose was particularly apparent within 2-7 hours after administration. Ethmozine treatment, as described above, delayed atrioventricular conduction, causing however no significant decrease in heart rate, nor depressing cardiac output and myocardial function; arterial blood pressure and myocardial oxygen requirement remained basically unchanged either. Unlike propranolol effect on cardiac rhythm undulating pattern, there is evidence that ethmozine mechanism of action involves sympathetic activation. Ethmozine had to be discontinued in 10.4% of the 35.4% of patients with side effects.