title: Flow effect on lesion formation in RF cardiac catheter ablation.
abstract: This study investigated the flow effect on the lesion formation during radio-frequency cardiac catheter ablation in temperature-controlled mode. The blood flow in heart chambers carries heat away from the endocardium by convection. This cooling effect requires more power from the ablation generator and causes a larger lesion. We set up a flow system to simulate the flow inside the heart chamber. We performed in vitro ablation on bovine myocardium with three different flow rates (0 L/min, 1 L/min and 3 L/min) and two target temperatures (60 degrees C and 80 degrees C). During ablation, we also recorded the temperatures inside the myocardium with a three-thermocouple temperature probe. The results show that lesion dimensions (maximum depth, maximum width and lesion volume) are larger in high flow rates (p<0.01). Also, the temperature recordings show that the tissue temperature rises faster and reaches a higher temperature under higher flow rate.
authors.affiliation: Department of Electrical and Computer Engineering, University of Wisconsin-Madison, 53706, USA.
authors.forename: H
authors.initials: H
authors.lastname: Cao
authors.forename: V R
authors.initials: VR
authors.lastname: Vorperian
authors.forename: S
authors.initials: S
authors.lastname: Tungjitkusolmun
authors.forename: J Z
authors.initials: JZ
authors.lastname: Tsai
authors.forename: D
authors.initials: D
authors.lastname: Haemmerich
authors.forename: Y B
authors.initials: YB
authors.lastname: Choy
authors.forename: J G
authors.initials: JG
authors.lastname: Webster
mesh_terms: D000818:Animals; D006348:Cardiac Surgical Procedures / Q000379:methods; D017115:Catheter Ablation / Q000379:methods*; D002417:Cattle; D006439:Hemodynamics / Q000502:physiology*; D008955:Models, Cardiovascular; D009206:Myocardium / Q000473:pathology