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Forty Years of Invasive Clinical Electrophysiology: 1967–2007

In 2007, we marked the 40th anniversary of the birth of invasive clinical electrophysiology. Of course, before 1967, cardiac arrhythmias were documented electrocardiographically, and their possible mechanisms were analyzed ingeniously and explained beautifully by giants such as Katz and Pick,1 Scherf and Schott,2 and Bellet.3

In the 1940s and 1950s, Hecht,4 Latour and Puech,5 and Giraud et al6 used catheters to measure intracardiac electric activity and to record the sequence of cardiac activation. In 1958, Furman and Robinson7 showed that in patients with atrioventricular block, the heart could be stimulated by connecting an intraventricular catheter to a stimulator.

In 1967, the analysis of the site of origin and mechanism of cardiac arrhythmias became possible in the intact human heart through the use of programmed electric stimulation combined with intracardiac activation mapping. Independently, Durrer et al7 in Amsterdam (in patients with the Wolff-Parkinson-White syndrome) and Coumel and coworkers8 in Paris (in a patient with an atrioventricular junctional tachycardia) showed that by connecting intracardiac catheters to a versatile stimulator, it was possible to reproducibly initiate and terminate clinically occurring tachycardias and to identify the site of origin of the tachycardia and, in the case of a reentrant mechanism, the pathway of the arrhythmia by placing catheters at different sites in the heart.8,9 Soon after, on both sides of the Atlantic, this technique was used to unravel the place of origin of different types of supraventricular tachycardias.10–14 The first book on the use of programmed stimulation of the heart in the analysis of supraventricular tachycardias was published in 1971.15

In the late 1960s, Scherlag et al16 made another important breakthrough in the analysis of cardiac arrhythmias with the reproducible registration of the His bundle electrogram. Not only did this advance …