Comparative antidysrhythmic profiles of bepridil, amiodarone and disopyramide in the guinea-pig and dog.

The antiarrhythmic effects of a novel antianginal agent, bepridil, were compared with four reference products. Bepridil increased the effective refractory period in isolated guinea-pig atria slightly more than hydroquinidine, and much more than disopyramide and lidocaine. Amiodarone was without effect. The doses of bepridil necessary for correcting atrial fibrillation induced by local application of aconitine, were similar for hydroquinidine, higher than for lidocaine and disopyramide but lower than for amiodarone. Bepridil depressed the tachycardia and ventricular fibrillation induced by perfusing aconitine in anesthetized guinea-pigs at doses of the same order of magnitude as for disopyramide and hydroquinidine. Lidocaine only exerted weak activity in this system, while amiodarone was without effect. Bepridil was less active than the four reference products, particularly disopyramide, on rhythm disorders induced by coronary artery ligation.