Use of the Inverse Solution Guidance Algorithm method for RF ablation
catheter guidance
Abstract
We previously introduced the Inverse Solution Guidance Algorithm (ISGA)
methodology using a Single Equivalent Moving Dipole model of cardiac
electrical activity to localize both the exit site of a re-entrant
circuit and the tip of a radiofrequency (RF) ablation catheter. The
purpose of this study was to investigate the use of ISGA for ablation
catheter guidance in an animal model. Ventricular tachycardia (VT) was
simulated by rapid ventricular pacing at a target site in eleven
Yorkshire swine. The ablation target was established using three
different techniques: a pacing lead placed into the ventricular wall at
the mid-myocardial level (Type-1), an intracardiac mapping catheter
(Type-2), and an RF ablation catheter placed at a random position on the
endocardial surface (Type-3). In each experiment, one operator placed
the catheter/pacing lead at the target location, while another used the
ISGA system to manipulate the RF ablation catheter starting from a
random ventricular location to locate the target. The average
localization error of the RF ablation catheter tip was 0.31 ± 0.08 cm.
After analyzing ~35 cardiac cycles of simulated VT, the
ISGA system’s accuracy in locating the target was 0.4 cm after 4
catheter movements in the Type-1 experiment, 0.48 cm after 6 movements
in the Type-2 experiment, and 0.67 cm after 7 movements in the Type-3
experiment. We demonstrated the feasibility of using the ISGA method to
guide an ablation catheter to the origin of a VT focus by analyzing a
few beats of body surface potentials without electro-anatomic mapping.