Non-contact mapping system accurately localizes right-sided accessory pathways in type B Wolff-Parkinson-White syndrome

Single accessory pathway with multiple insertions? First-in-human 3D visualization using dipole charge density mapping: a case report

Background

Accessory pathways (APs) with multiple atrial insertions are often unrecognized and associated with initial catheter ablation (CA) failure. Recently, a novel dipole charge density mapping (DCDM) system was developed that allows mapping of complex arrhythmias based on a single beat. We aim to present the first-in-human report of 3D visualization of a single AP with two atrial insertion sites using high-resolution DCDM.

Case summary

A 43-year-old man with recurrent symptomatic atrioventricular re-entrant tachycardia and previously failed CA attempts underwent repeated CA using DCDM. Dipole charge density mapping identified two quasi-simultaneous early atrial activation sites at the left lateral and left anterolateral atrial aspects of the mitral annulus, suggesting the presence of a single AP with dual atrial insertion sites. Successful radiofrequency CA was performed at the mid-body of the AP.

Discussion

The true prevalence of APs with multiple atrial insertion sites may be higher than currently reported. This is the first-in-human report of 3D visualization of a single AP with two atrial insertion sites using high-resolution DCDM. Dipole charge density mapping allows the accurate localization of APs with multiple insertion sites based on a single beat.

Catheter Ablation of Right-Sided Accessory Pathways in Adults Using the Three-Dimensional Mapping System: A Randomized Comparison to the Conventional Approach

Three-dimensional (3D) mapping and navigation systems have been widely used for the ablation of atrial fibrillation and ventricular tachycardia, but the applicability of these systems for the ablation of supraventricular tachycardia (SVT) due to right-sided accessory pathways (RAPs) remains unknown. The goal of this prospective randomized study was to compare the safety, efficiency, and efficacy of nonfluoroscopic and conventional fluoroscopic mapping techniques in guiding catheter ablation of SVT due to RAPs. Of the 393 consecutive patients with SVT who were randomized to receive either conventional fluoroscopic or Ensite NavX mapping-guided ablation, 64 patients with RAPs were included for analysis. Endpoints for ablation were no evidence of RAP conduction and no inducible atrioventricular reentrant tachycardia (AVRT). The 3D group showed fewer ablation pulses and a shorter total ablation time compared to the conventional group, although the acute procedural success did not differ significantly between the two groups. Total procedure time, electrophysiological study time, total fluoroscopy time, and cumulative radiation doses were also significantly reduced in the 3D group. Patients in the conventional group with a right atrium diameter (RAD) ≥ 47 mm required a longer fluoroscopy time. There was no significant difference in the recurrence rates between the two groups over a follow-up period of 3 to 29 months. There were no permanent complications. The 3D mapping system may be a preferred alternative for patients with AVRT due to RAPs, especially for patients with a large RAD (≥ 47 mm).