Title: 1967–1997: Thirty years of cardiac arrhythmias
Abstract: I had the good fortune of doing my cardiology training in the 1960s in the Wilhelmina Gasthuis, the University of Amsterdam. Headed by professor Dirk Durrer (Fig. 1), the department of cardiology was a hive of activity, unravelling the electrical activity of the heart. Durrer, who was an original thinker, an inspiring leader, and an outstanding teacher, had assembled a group of physicians including Drs Hans Buller, Bart Dekker, Gerrit Freud, Michiel Janse, Frits Meijler and Rudolf van Dam, who were all actively involved in seeking insight into basic processes governing cardiac excitation and the genesis of cardiac arrhythmias. The cooperation between cardiology and medical physics was of enormous significance in Amsterdam. Professor Henk van der Tweel in his Department of Medical Physics played a key role in the development of instruments for stimulating the heart and recording its electrical activity. In 1967 Durrer and Roos revealed that the earliest ventricular epicardial activation during sinus rhythm occurred close to the atrioventricular ring. This was demonstrated in a patient with the WolffParkinson-White syndrome (WPW), who was operated upon in Leiden by Professor Brom because of an atrial septal defect. The question then arose, how could the arrhythmias be reproduced? In 1933, Wolferth and Wood suggested that there may be two atrioventricular (AV) connections in the WPW syndrome. This would make it possible for arrhythmias to occur by using a circuit with anterograde AV conduction over one connection and retrograde (ventriculo-atrial) conduction over the other. Durrer and Roos’ epicardial activation map of the patient with WPW proved the existence of a second AV connection. This prompted the development of a versatile stimulator by the Department of Medical Physics (Professor Van der Tweel, Dr Jan Strackee and Leo Schoo), which would allow programmed electrical stimulation of the heart with such accuracy that the hypothesis of a circus movement tachycardia could be tested.