Mapping and ablation of typical and atypical accessory pathways

Accessory pathways (APs) are one of the longest standing targets for mapping and ablation, previously surgical but now almost exclusively catheter based. This chapter reviews the electrocardiographic and catheter-based principles of mapping related to APs. While catheter ablation, especially radiofrequency, began with elimination of APs, much greater focus currently exists on treatment of atrial fibrillation or ventricular tachycardia. While invasive electrophysiological study will provide definitive localization of an AP in Wolff-Parkinson-White syndrome, the 12-lead electrocardiogram offers important clues to an AP’s anatomical position. Simple, non-invasive, and cost-effective, a 12-lead can assist with both preprocedural planning and risk assessment prior to ablation. The non-coronary cusp has become a more frequent location for catheter ablation, especially for anteroseptal atrial tachycardias (parahisian or perinodal) having earliest atrial activation near the His A. Similarly, some anteroseptal APs have been ablated without injury to the normal conduction system from the non-coronary cusp or right coronary cusp.

Duke Scholars

Author James Patrick Daubert Medicine, Cardiology