Nonsurgical electric ablation (fulguration) of tachycardias

Drugs and antiachycardia devices provide useful palliative therapy for many arrhythmias. Definitive treatment of tachycardias has previously required surgery, ranging from cervical sympathectomy for patients with long QT interval syndromes to open heart surgery for most other arrhythmias. Interest in the possibility of the use of intracardiac catheter electrodes for delivery of destructive electrical energy to the tachycardia site is not new, but a series of recent animal studies has laid the groundwork for clinical application of the technique. The possibility of a 'nonsurgical cure' is very appealing. Although the final role of this experimental form of therapy remains undetermined, there are sufficient data to justify continuing investigation, and to anticipate an increase in clinical applications. Several types of ablation are under investigation, including electric shock (fulguration), laser, radiofrequency, and others. Fulguration has thus far received the most attention. In this article, 'ablation' will mean 'fulguration' unless otherwise indicated. Catheter ablation may be directed either at the tachycardia focus or circuit, or at an atrioventricular conduction pathway. The technique requires detailed electrophysiologic investigation by experienced physicians, not only because of immediate potential dangers, but because irreversible changes may be produced that could affect the rest of the patient's life. For example, ablation of the atrioventricular conduction system commits the patient to a lifetime of cardiac pacing.