Catheter Ablation -> Atrial Fibrillation & Atrial Flutter: -> Ablation Techniques D-AB09 - Advances in Radiofrequency Ablation Lesion Science: Optimizing Settings and Outcomes (ID 46) Abstract

D-AB09-06 - Comprehensive Investigation To Determine The Optimal Conditions For High Power Short Duration Rf Ablation Using A Novel, Flexible Tipped, Force Sensing Catheter (ID 1424)


Background: High power short duration (HPSD) RF ablation with irrigated catheters may reduce procedure time and improve safety, however comprehensive data, including thresholds for safety with HPSD ablation, are limited.
Objective: To determine optimal HPSD ablation conditions for safety and efficacy with a novel flexible tipped, contact force sensing, RF ablation catheter.
Methods: RF ablation lesions were created in a thigh muscle model (16 swine) to determine adverse event occurrence and lesion size over a wide range of conditions (51-82 W, 2-40 g, 8-40 ml/min irrigation). An intracardiac study was performed (12 swine) to characterize thresholds for steam pop occurrence. Focal and PVI lesion sets were created in a 2ndintracardiac study (14 swine) with combinations of RF power, duration, and contact force. PV isolation was tested post ablation, animals were sacrificed and lesions were measured.
Results: A logistic regression model was applied to determine steam pop likelihood under various conditions. The figure illustrates the range of RF power, duration, and contact force where safe and effective lesions could be created in the 2ndintracardiacstudy (n=14 swine, n=290 PVI lesions). Under these conditions, atrial focal lesions ranged in width from 4.2-12.5 mm and were transmural 80.8% of the time. Acute PVI was achieved in 13/14 veins.
Conclusion: Safe and effective HPSD lesions can be created using this novel, flexible tipped, force sensing RF ablation catheter. Optimal lesions for safety and efficacy were created at 60-70 W for <8 s with < 20 g contact force. Chronic studies are ongoing to assess RF parameter refinements and long term lesion durability using these conditions.