Control of antiarrhythmic drug therapy by electrophysiologic testing

Pioneering electrophysiological studies in the 1970s by Wellens and Josephson showed that in the majority of patients who have survived an episode of sustained ventricular tachycardia, the arrhythmia can be initiated and terminated by programmed electrical stimulation in the catheterization laboratory. Later work demonstrated that this method can also be applied to patients who have survived an episode of cardiac arrest due to ventricular fibrillation, not associated with acute myocardial infarction. As a consequence, serial electrophysiologic testing can be recommended to assess the efficacy of antiarrhythmic agents for the guidance of long-term treatment of these patients. This report focuses on some aspects of this method such as the recommended indications at present, differences in the electrophysiologic protocols among various authors, the results to be obtained by serial electrophysiologic testing, and finally discusses the question--not yet resolved--whether an improvement of outcome can thereby be achieved.