[The pharmacology of the new combined anti-arrhythmia preparation metatsizin].

: The combined antiarrhythmic effect of ethmosin and ethacisin in various dose ratios was studied in conscious dogs with two-stage ligation of the coronary artery (after Harris). A 6:1 ratio was found to be optimal for manifestation of the antiarrhythmic effect. In such a ratio of the doses the antiarrhythmic effect of a combination of ethmosin and ethacisin is essentially higher than the activity of each component. On the grounds of these data a combined antiarrhythmic drug methacisin was developed. It possesses a broad spectrum of antiarrhythmic activity. The drug is effective on models of arrhythmias specific of class I, III, and IV antiarrhythmics. Metacisin does not change hemodynamics and activity of the heart. Study of metacisin pharmacokinetics showed that it possesses bioavailability twice that of ethmosin tablets taken separately and four times that of ethasicin.