Surgical treatment of left free wall accessory pathways of atrioventricular conduction of the Kent type

This report relates the surgical experience with 79 patients with arrhythmias who had 82 left free wall accessory pathways of atrioventricular conduction of the Kent type. The current operation for the interruption of the pathway consists of two steps. First, the localization of the pathway is done by mapping the epicardial excitation sequence of the atria and the ventricles. This is followed by a set group of maneuvers needed to divide the pathway, which is not visible or palpable. First, an endocardial atrial incision is made just above the anulus fibrosus extending 1.5 to 2.0 cm on each side of the pathway's crossing point. Then, a wide separation of the coronary sulcus fat from the atria and ventricles is done. Finally, superficial fibers of the ventricular myocardium are separated from the anulus fibrosus. The surgical problems such as the possible coronary sinus origin of a pathway and the proximity of pathways to the left fibrous trigone are discussed, both from the electrophysiological and the surgical standpoints. The overall success rate for interruption of left free wall pathways has been 90% with no failure in the last 34 patients.