Accessory pathways

Over a century has passed since Stanley Kent reported in 1893 on the pathohistologic finding of myocardial fibers crossing the lateral aspect of the sulcus atrioventricularis which he thought were part of the normal ?nodal? connection between the atrium and ventricle [23j. Although the interpretation of his findings was wrong, he was the first to describe an accessory connection between atrial and ventricular myocardium and these pathways are still referred to as ?Kent fibers?. In 1930, Wolff, Parkinson und White described a ?syndrome? that consisted of a short PQ interval with bundle branch block on the surface ECG together with the clinical picture of paroxysmal tachycardia [46j. The authors did not recognize the anatomic and electrophysiological correlate of their findings but their report led to more investigation. Holzmann and Scherf [21j are thought to be the first to describe our current understanding of the pathogenesis of WPW syndrome in terms of a reentrant circuit involving the AV node and an extranodal accessory pathway.