Progress in cardiac arrhythmia ablation: potential for broader application and shorter procedure time

Catheter ablation is a very effective form of therapy for cardiac arrhythmias. Using present techniques, however, its application is limited only to a select type of arrhythmia involving discrete areas of the heart. The more common arrhythmias, such as atrial fibrillation and ventricular tachycardia, remain difficult to treat. It seems likely that deeper and larger ablations would be necessary for abolishing reentry substrates of VT and that long linear ablations would be needed for preventing propagation of atrial fibrillation. Improvements in energy delivery techniques and the use of alternative energy modalities are promising developments that may yield a broader scope of lesion generation. Cooling mechanisms have allowed for more effective RF delivery and the generation of larger lesions. Laser, ultrasound, and microwave ablations have also been shown to produce deeper lesions. Linear lesions could be accomplished with RF ablation using multiple electrode configurations or with MW using long antennae. Future ablation procedures are likely to include complex arrhythmias and use one of these newer modalities. The more powerful and versatile modalities may become the most useful ones as they, coupled with parallel improvements in mapping technology, would facilitate the procedures by minimizing morbidity and improving patients' tolerance. At present, the more simple procedures do not require anesthesia or intensive cardiorespiratory monitoring, but because the procedures are being applied to include more complex arrhythmias, such monitoring may become necessary.