PROPHYLACTIC TREATMENT OF SWINE WITH BRETYLIUM FOR EXPERIMENTAL CARDIAC-CATHETERIZATION

We evaluated a cryothermic ablation catheter for potential use in trea ting supraventricular tachycardia by cardiac catheterization in miniat ure swine. Cardiac catheterization was performed on anesthetized minia ture swine by using multiple catheters that were inserted bilaterally by either percutaneous or cutdown techniques into the femoral veins. W e performed electrophysiologic tests according to standard atrial and ventricular electrical stimulation protocols. Manipulation of catheter s in the tricuspid valve area and right ventricle was an essential par t of the study. During an initial study of five swine, catheter manipu lation produced sustained and nonsustained ventricular tachycardia and ventricular fibrillation. To prevent arrhythmias, bretylium (5 mg/kg) was administered intravenously 10 minutes before catheter manipulatio n and repeated every 30 minutes throughout the procedure. Since the us e of bretylium was instituted, there have been no cases of ventricular fibrillation in a series of 20 animals. We determined that bretylium is effective in the suppression of ventricular arrhythmias in swine un dergoing cardiac catheterization.