A Pilot Study on Parameter Setting of VisiTag™ Module during Pulmonary Vein Isolation

Area of Science:

• Electrophysiology
• Cardiac Ablation Technology

Background:

• Pulmonary vein isolation (PVI) is a key treatment for atrial fibrillation (AF).
• The CARTO 3 system with its VisiTag™ module aids in real-time ablation lesion assessment.
• Optimizing predefined criteria (OPC) for the VisiTag™ module is crucial for successful PVI.

Purpose of the Study:

• To determine the optimal predefined criteria (OPC) for the VisiTag™ module filters.
• To minimize conduction gaps (CG) and maximize contiguous encircling ablation lines (CEAL) during PVI.

Main Methods:

• Thirty AF patients undergoing PVI using a Thermocool SmartTouch catheter were enrolled.
• Ablation lesions were automatically tagged based on VisiTag™ module criteria.
• Different parameter settings, including catheter movement limits and force-over-time (FOT), were evaluated.

Main Results:

• Initial settings (3mm distance limit, 20s, FOT off) yielded 60 CEAL but 26 CGs.
• Adjusting FOT to 5g/50% stability resulted in 22 tag gaps (TG), 20 with CGs.
• Reablation at TG sites eliminated most CGs, but aggressive FOT settings (10g/50%) eliminated CEAL.

Conclusions:

• A 3mm distance limit for at least 20s combined with FOT set to a minimal force of 5g and 50% stability time are proposed as OPC.
• These settings appear to balance lesion completeness and minimize gaps during PVI.