of Programmed Electrical Stimulation of the Heart in the Study and Treatment of Tachycardias

SUMMARY A review is given on the use of programmed electrical stimulation of the heart in patients suffering from tachycardia. The application of this technique makes it possible to evaluate mechanisms of tachycardia directly in the human heart. By repeating the same stimulation program following drug administration the effect of drugs on arrhythmia mechanisms can be studied. There are IN 1967 Durrer et al.1 and Coumel et al. ' independently reported on the use of programmed electrical stimulation of the heart in the study of patients suffering from tachy-cardia. This was rapidly followed by articles on initiation and termination of different types of tachycardia from both sides of the Atlantic Ocean.3 In this article value and limitations of programmed elec-trical stimulation in patients with tachycardia will be analyzed. An attempt will be made to answer the following questions: 1) How useful is the technique for determining mechanism, site of origin and pathway of tachycardia; 2) Can the technique help in selecting appropriate treatment; and 3) Did information derived from application of this technique improve the diagnostic ability of the 12-lead elec-trocardiogram. The Method As shown in table 1 programmed electrical stimulation of the heart requires intracardiac electrode catheters at different locations, extracardiac recordings and a stimulator. Table 2 summarizes the specifications of the stimulator