A Novel Wave-speed Mapping Method for Visualizing Accessory Pathways in Wolff-Parkinson-White Syndrome

Introduction: Catheter ablation (CA) is the first-line treatment with a high success rate for patients with symptomatic Wolff-Parkinson-White syndrome, while three-dimensional (3D) mapping systems enable the identification of accessory pathways (APs). We aimed to develop a novel mapping method using wave-speed mapping (WSM) to determine AP locations and CA outcomes.

Methods and results: This study included 19 patients diagnosed with atrioventricular (AV) reciprocating tachycardia. We compared local activation time (LAT) mapping and WSM, and analyzed the relationship between the "high-speed islets" in WSM and successful ablation sites. Sixteen APs were located on the left, three on the septum, and one on the right side. The median number of mapping points and mapping time were 1451 points and 14.6 min, respectively. All 20 APs in the 19 patients were eliminated using "high-speed islets" in WSM. Eleven APs (55%) were eliminated after the first ablation application. One patient with an anteroseptal AP close to the AV node underwent cryoablation to avoid an AV block. The AP width in the 3D mapping system was significantly narrower in WSM than in LAT mapping (5.8 ± 4.0 mm vs. 10.4 ± 3.2 mm, p < .001). One patient experienced an AP recurrence, successfully eliminated using WSM-guided CA in a repeat procedure. During 13.1 ± 8.3 months of follow-up, all patients remained free of any supraventricular tachycardias.

Conclusion: WSM is a novel mapping method for visualizing APs as "high-speed islets" and guides a more precise ablation site than LAT mapping.