Dangerous Ventricular Arrhythmias -- Can We Predict Drug Efficacy?

Only two decades ago, the treatment of patients with recurrent ventricular tachycardia and fibrillation was entirely empirical and relied exclusively on drug therapy. The proarrhythmic effects of drug treatment and the possibility that such treatment could be deleterious were virtually unknown. The clinical techniques of cardiac electrophysiology and electrocardiographic (Holter) monitoring, just beginning to be used in the 1960s, were to change that approach beyond all recognition. With prolonged electrocardiographic monitoring,1 important data could be obtained about cardiac arrhythmias in a variety of conditions. Most important, such noninvasive monitoring became a method of assessing the effects of antiarrhythmic drugs on . . .