His bundle interruption for control of inappropriate ventricular responses to atrial arrhythmias.

Forty-two patients with life-threatening or disabling atrial arrhythmias are discussed. Fifteen had Kent bundles as the basis for the reentry tachycardia, while 27 had arrhythmias that originated in or above the atrioventricular (AV) node. Nineteen of the latter had an AV node that conducted atrial impulses rapidly to the ventricle. These patients were classified as having enhanced conduction through the AV node, a diagnosis based on clinical and electrophysiological studies. Initially, the technique employed for His bundle interruption was, either separate or in combination, blind suture, electrocauterization, and incision of the septal portion of the right atrium. The technique later adopted was sharp division of the atrial septum at its attachment to the right fibrous trigone. Cryothermia was used in 31 patients. There were four failures. In the group in whom sharp division was used. there were two failures among 11 patients. Two patients, however, had to have a second operation. Following AV node-His bundle interruption, a junctional rhythm resulted and a pacemaker was always installed. Our studies indicate that interruption of atrial to ventricular conduction is a satisfactory operation for atrial arrhythmias that are disabling or life threatening and that are refractory to vigorous medical therapy. Cryothermic ablation is the preferable technique. However, if this is not successful, then division is required of the AV nod-His bundle junction by interruption of the insertion of the atrial septum into the right fibrous trigone.