High-energy catheter ablation of cardiac arrhythmias: an outmoded technique in the 1990s.

Catheter ablation has become an accepted technique for creating complete heart block in patients with drug refractory supraventricular tachycardias. However, it remains experimental for other indications, such as ablation of accessory pathway or ventricular tachycardia. The use of high energy defibrillator discharges is associated with adverse effects which greatly contribute to the limitations of the technique. Advances in technology have led to newer methods, such as radiofrequency and low energy capacitive discharge, which hold significant advantages over the conventional high energy technique, to the extent that the use of defibrillator discharges should now be considered outmoded and potentially damaging. Radiofrequency is the technique of choice for accessory pathway ablation and modification of AV conduction, and low energy capacitive discharge is the preferred method for creation of complete heart block. There are currently no acceptably safe and efficacious catheter techniques for treating ventricular tachycardia, and more research needs to be done in this area. The potential for the success of these techniques depends to an extent on the creation of new standards of practice for catheter ablation. There has been no unbiased comparative assessment of the different techniques, and consequently no consensus exists on the preferred technique and technologies which should be used. Only within the framework of these standards can the technique achieve significant clinical utility.