ABSTRACT
Nine patients aged 47 to 74 years underwent endocavitary destruction of the bundle of His because of paroxysmal arrhythmias resistant to medical therapy. Four patients had paroxysmal atrial fibrillation, 2 had paroxysmal atrial flutter, 1 had reentrant atrial tachycardia, 1 had paroxysmal atrial tachycardia and 1 had an intranodal reentrant tachycardia. One patient had already undergone "surgical ablation" of the His bundle without success. A tripolar or bipolar catheter was introduced via the femoral vein and the His potential localised by bipolar and then unipolar recordings. The lead with the greatest His potential was connected to an external defibrillator and the other pole connected to a metal plaque positioned under the patient's left shoulder. An electrical shock of 200 to 400 joules was administered, in some cases repeatedly. Eight of the 9 patients developed complete atrioventricular block after the shock. This was only temporary in 3 cases, necessitating another shock in 2 cases; the procedure was not repeated in the 3rd case. After 30 minutes of persistent AV block a pacemaker was implanted; 7 of these 8 patients had VVI and I patient (intranodal reentry) DDD pacing. The follow-up period ranges from 1 to 18 months. None of the patients have had symptoms of paroxysmal arrhythmia; in the long-term, there was one initial failure. Of the other 8 cases, 4 remain in complete AV block, 2 have 2nd degree and 21st degree AV block. Three patients have associated antiarrhythmic therapy with quinidine or verapamil. No side effects were observed.(ABSTRACT TRUNCATED AT 250 WORDS)
