An Experiment Study on the Surgical Production of Atrioventricular Block by Direct Current Electrocautery / 日本心臓血管外科学会雑誌

ABSTRACT

Therapeutic AV block has been preferred in drug-resistant cases, although concurrent pacemaker implantation is mandatory. If it is technically possible to control surgically produced AV block to the first or second degree, this would certainly make conjoined use of a demand pacemaker quite unnecessary. This concept prompted us to undertake an experimental study, in which we succeeded in producing first to third degree AV block in 30 mongrel dogs through ablation of the AV node by applying direct current from the epicardial side. From immediately after starting ablation a stepwise progressive prolongation of the PQ interval was noted, with eventual development of third degree AV block. Histopathologically, the lesion consisted of coagulation necrosis which involved an average of 95% of the AV node in animals developing third degree AV block and an average of 66% in those with first degree AV block. These results suggest that our surgical procedure, if technically refined to permit ablation of the AV node to the desired extent, will provide an acceptable means of treating supraventricular tachyarrhythmia without requiring permanent pacemaker implantation.