Juan J Pérez1, Ana González-Suárez2,3, Timothy Maher4, Hiroshi Nakagawa5, Andre d'Avila4, Enrique Berjano1. 1. Department of Electronic Engineering, BioMIT, Universitat Politècnica de València, Valencia, Spain. 2. Electrical and Electronic Engineering Department, National University of Ireland Galway, Galway, Ireland. 3. Translational Medical Device Lab, National University of Ireland Galway, Galway, Ireland. 4. Division of Cardiovascular Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA. 5. Department of Cardiovascular Medicine, Cleveland Clinic, Cleveland, Ohio, USA.
Abstract
OBJECTIVE: To model the evolution of peak temperature and volume of damaged esophagus during and after radiofrequency (RF) ablation using low power-moderate duration (LPMD) versus high power-short duration (HPSD) or very high power-very short duration (VHPVSD) settings. METHODS: An in silico simulation model of RF ablation accounting for left atrial wall thickness, nearby organs and tissues, as well as catheter contact force. The model used the Arrhenius equation to derive a thermal damage model and estimate the volume of esophageal damage over time during and after RF application under conditions of LPMD (30 W, 20 s), HPSD (50 W, 6 s), and VHPVSD (90 W, 4 s). RESULTS: There was a close correlation between maximum peak temperature after RF application and volume of esophageal damage, with highest correlation (R2 = 0.97) and highest volume of esophageal injury in the LPMD group. A greater increase in peak temperature and greater relative increase in esophageal injury volume in the HPSD (240%) and VHPSD (270%) simulations occurred after RF termination. Increased endocardial to esophageal thickness was associated with a longer time to maximum peak temperature (R2 > 0.92), especially in the HPSD/VHPVSD simulations, and no esophageal injury was seen when the distances were >4.5 mm for LPMD or >3.5 mm for HPSD. CONCLUSION: LPMD is associated with a larger total volume of esophageal damage due to the greater total RF energy delivery. HPSD and VHPVSD shows significant thermal latency (resulting from conductive tissue heating after RF termination), suggesting a requirement for fewer esophageal temperature cutoffs during ablation.
OBJECTIVE: To model the evolution of peak temperature and volume of damaged esophagus during and after radiofrequency (RF) ablation using low power-moderate duration (LPMD) versus high power-short duration (HPSD) or very high power-very short duration (VHPVSD) settings. METHODS: An in silico simulation model of RF ablation accounting for left atrial wall thickness, nearby organs and tissues, as well as catheter contact force. The model used the Arrhenius equation to derive a thermal damage model and estimate the volume of esophageal damage over time during and after RF application under conditions of LPMD (30 W, 20 s), HPSD (50 W, 6 s), and VHPVSD (90 W, 4 s). RESULTS: There was a close correlation between maximum peak temperature after RF application and volume of esophageal damage, with highest correlation (R2 = 0.97) and highest volume of esophageal injury in the LPMD group. A greater increase in peak temperature and greater relative increase in esophageal injury volume in the HPSD (240%) and VHPSD (270%) simulations occurred after RF termination. Increased endocardial to esophageal thickness was associated with a longer time to maximum peak temperature (R2 > 0.92), especially in the HPSD/VHPVSD simulations, and no esophageal injury was seen when the distances were >4.5 mm for LPMD or >3.5 mm for HPSD. CONCLUSION: LPMD is associated with a larger total volume of esophageal damage due to the greater total RF energy delivery. HPSD and VHPVSD shows significant thermal latency (resulting from conductive tissue heating after RF termination), suggesting a requirement for fewer esophageal temperature cutoffs during ablation.