The antiarrhythmic effects of Bidisomide, a new class I antiarrhythmic drug is investigated in early-phase ventricular arrhythmias induced by coronary artery occlusion and reperfusion in anesthetized rats. Bidisomide (5 mg/kg) reduces the number of premature ventricular complexes and the incidence of ventricular tachycardia and ventricular fibrillation similarly to Mexiletine (MXT) and Disopyramide (DSP) in rats with ventricular arrhythmias induced by coronary artery occlusion. In rats with ventricular arrhythmias induced by coronary artery reperfusion following a 5 min coronary occlusion, the antiarrhythmic effects of 5 mg/kg of Bidisomide are similar to those of the same doses of MXT and DSP. All three drugs significantly slow the heart rate.