Transvenous ablation of the atrioventricular conduction system by laser irradiation under endoscopic control

We report ten successful experiments of transvenous destruction of the His bundle by laser radiation. An endoscope coupled with a special laser catheter was introduced through the jugular vein into the right atrium of dogs. The tip of the laser catheter was positioned in front of A-V conduction system under visual control using anatomic landmarks. Injection of saline solution coaxial with the laser power-transmitting fiber was performed before and during laser coagulation. Twenty watts constant wave Nd-YAG laser operating at 1.06 micron was enough to produce complete A-V block in approximately 15 sec. The safety of the proposed technique is especially discussed.