Abstract 16064: Direct Visualization of Epicardial Structures and Ablation Utilizing a Visually-Guided Laser Balloon Catheter
Background: Intrapericardial mapping and ablation can be utilized to target epicardial arrhythmic circuits. Current epicardial ablation strategies are associated with risk of damage to adjacent structures, including the coronary vasculature and phrenic nerves.
Objectives: The purpose of this study was to evaluate the feasibility of an investigational, visually-guided laser balloon catheter for manipulation within the pericardial space, visualization of epicardial structures, and delivery of laser ablation lesions to the ventricular myocardium.
Methods: Pericardial access was obtained in 4 anesthetized swine by sub-xyphoid puncture. The laser balloon catheter was introduced into the pericardial space via a deflectable sheath, and was manipulated to pre-defined regions in all animals, including the right and left ventricular free walls, ventricular apex, the left atrial appendage and the left and right A-V grooves. Visually-guided laser ablation was performed on the ventricular myocardium, with post-mortem examination of lesion size and depth.
Results: The laser ablation catheter could be manipulated to all targeted regions in all animals (see figure). Associated structures, including epicardial coronary arteries and veins as well as an endocardial catheter in the left atrial appendage, were easily visualized. A total of 9 laser energy applications at varying power/time settings were performed. Ablation utilizing moderate (7–8.5W) power produced relatively uniform lesions (diameter 5–12 mm, depth 6–9 mm), while high (14W) power produced a visible “steam pop” with a large, hemmorhagic lesion (22x11x11mm).
Conclusions: The investigational laser balloon catheter can be manipulated within the epicardial space, and allows for direct visualization of surrounding structures during the creation of epicardial ablation lesions. Titration of laser power can be utilized to create moderate-sized ablation lesions while avoiding steam pops.
- © 2010 by American Heart Association, Inc.