Local impedance drop-guided versus lesion size index-guided pulmonary vein isolation

Area of Science:

• Electrophysiology
• Cardiology
• Medical Devices

Background:

• Local tissue impedance drop (LID) and lesion size index (LSI) are key technologies for predicting effective lesion formation during pulmonary vein isolation (PVI).
• Atrial fibrillation (AF) treatment efficacy relies on durable PVI, making guidance technologies crucial.

Purpose of the Study:

• To compare the acute and long-term efficacy of LID-guided versus LSI-guided radiofrequency PVI for treating atrial fibrillation.
• To evaluate differences in ablation time, lesion gaps, and arrhythmia recurrence between the two guidance methods.

Main Methods:

• Retrospective analysis of two patient groups (LID-guided, n=35; LSI-guided, n=31) undergoing radiofrequency PVI.
• LID-guided ablation stopped at LID plateau; LSI-guided ablation used contact force with target LSI values.
• Standardized power settings and inter-lesion distance were used, with gap mapping and touch-up ablation as needed.

Main Results:

• LSI-guided PVI achieved significantly shorter ablation times (25 min vs 30 min, p=0.035).
• The LID-guided group had more frequent PV gaps (74% vs 42%, p=0.016) and higher arrhythmia recurrence at 11.5 months (34.3% vs 16.1%, p=0.037).
• Redo procedures revealed similar rates of chronic PV reconnections (70% vs 67%).

Conclusions:

• LSI-guided PVI is associated with shorter ablation times and fewer acute PV gaps compared to LID-guided PVI.
• LSI-guided ablation demonstrates superior long-term efficacy in preventing arrhythmia recurrence and PV reconnections.
• Contact force-guided LSI technology represents an advancement over LID for achieving durable PVI in AF treatment.