Reduction of myocardial infarction and dysrhythmic activity by nafazatrom in the conscious rat.

The effects of nafazatrom (30 and 100 mg/kg b.i.d.) on myocardial lesions caused by coronary artery ligation were determined in rats. The treatment lasted ten days preceding and twenty days following the cardiac insult, and its effects were compared with the effects of oral 1% Tylose suspension as drug vehicle. Nafazatrom reduced the number of extrasystoles and the duration of ventricular tachycardia and fibrillation occurring in the early (0-10 min) and late phases (2-4 h) of cardiac arrhythmias observed in the controls. Pretreatment with nafazatrom reduced the size of the ultimate infarct by 36 and 48 percent (P less than 0.05), and by 28 and 39% (P less than 0.05) with post-ligature nafazatrom treatment.