Co-Author(s):
Megan Schmidt, PhD
Jean-pierre Lalonde, BS
David Ramirez, BS
Michael Getman, BS, MS
Southlake Regional Health Centre
596 Davis Dr. Newmarket, Ontario L3Y 2P9
Introduction | Objectives:Background: Contact force has proven to be influential for lesion formation in power-controlled radiofrequency (RF) ablation.  However, this technology provides a surrogate for lesion formation.  A diamond tip catheter ablation system was specifically designed to facilitate accurate temperature control and low irrigation for higher power and shorter duration radiofrequency delivery.   Objectives: Lesion formation and morphology from a temperature-controlled diamond tip RF ablation catheter is not well described.  We hypothesize that lesion formation from a temperature-controlled RF system is independent of applied force over short application duration.
Methods:Methods: This study examined lesion depth, lesion width, temperature, and ablation parameters of the DiamondTemp Ablation (DTA, Medtronic, Inc.) system for ablation applications delivered with a 5 second application duration and applied force (5, 10, and 30 g).  Lesions from perpendicular RF applications were analyzed in a stepwise fashion from a computational model, thermochromic gel data (n=12), and porcine thigh preparation (n=76) experiments.
Results:Results: Varying applied force (5, 10, and 30g) across an application duration of 5 seconds consistently generated comparable lesion dimensions for each model.  In the computational model, lesion depths from a 5 sec application with 5, 10, and 30 g of applied force were similar (3.7, 3.9, and 3.7 mm, respectively). Also, the 5 sec lesion depths in the gel model were consistent across applied force (5 g = 3.2±0.12 mm, 10 g = 3.5±0.13 mm, 30 g = 3.5±0.20 mm).  In the thigh model, the 5, 10, and 30 g applied forces for 5 sec created lesion depths of 3.1±0.46 mm, 3.2±0.97 mm, and 3.2±1.05 mm, respectively.
Conclusions:Conclusion: Lesion dimensions with the DTA temperature-controlled RF ablation system showed no marked change with increased applied force.  Short 5 second application duration generated consistent lesion dimensions across computational, thermochromic gel, and thigh models.