A rapid in vivo technique for preliminary screening of antiarrhythmic agents in mice

The search for new and better antiarrhythmic agents is complicated by the fact that currently there is no generally accepted, rapid, highly reproducible, in vivo screening technique which allows the use of large numbers of small animals for the purpose of statistical evaluation. Most of the methods available for use with small animals employ visual observation of the animal to assess electrophysiological events occurring in the heart. A rapid, inexpensive, in vivo screening technique is discribed, using aconitine as the arrhythmogenic agent. Arrhythmias induced by aconitine were measured by electrocardiogram (lead II). The times to onset of initial cardiac arrhythmias and ventricular tachycardia were determined and compared for significance in animals pretreated with physiological saline (control group), standard antiarrhythmic agents, and two drugs lacking antiarrhythmic activity. The results indicate that the method is a sensitive, rapid technique for preliminary in vivo screening of antiarrhythmic drugs.