title: Echocardiographic imaging of a basket catheter for mapping and ablation of ventricular tachycardia in pigs.
abstract: Our objective was to assess the feasibility and efficacy of the recently described left ventricular simultaneous deployment of a new multi-electrode mapping catheter and a standard radio-frequency ablation catheter in pigs, with echocardiography monitoring and fluoroscopy guidance. Introduction and deployment of both catheters in five healthy anesthetized pigs were guided on-line by fluoroscopy and monitored with transthoracic echocardiography. Heart rate and femoral blood pressure were also continuously monitored. Both catheters were deployed for up to 5 hours. Three animals underwent three to five radio-frequency energy applications. Left ventricular dimensions obtained from long axis two-dimensional echocardiography imaging before and after basket-catheter deployment in the left ventricular cavity, were 3.9 +/- 0.3 versus 3.7 +/- 0.6 cm at end-diastole and 2.8 +/- 1.1 versus 2.6 +/- 0.8 cm at end-systole, respectively (mean +/- standard error of the mean, p > 0.05). Shortening fraction measured from long axis two-dimensional echocardiography images before and after catheter deployment was 28% +/- 10% versus 25% +/- 5%, respectively (mean +/- standard error of the mean, p > 0.05). Additional findings included the following: (1) good conformation of the multi-electrode mapping catheter to the left ventricular dimensions during diastole; (2) absence of catheter-induced aortic and/or mitral insufficiency, as well as left ventricular outflow tract obstruction; (3) absence of damage to mitral and aortic valves or to the left ventricular wall. Postmortem examination and hemodynamic measurements confirmed these findings and showed only minor subendocardial hemorrhages; (4) radio-frequency energy application produced intracavitary bubbles, which were demonstrable echocardiographically, enabling identification of the gross anatomic location of ablation sites. Echocardiography during simultaneous deployment of multi-electrode mapping catheter and radio-frequency ablation catheters enables estimation of mechanical interaction with the left ventricle and detects interaction with myocardial/valvular function. During radio-frequency energy application, bubble production may identify gross anatomic location of ablation.
authors.affiliation: The Neufeld Cardiac Research Institute, Sackler School of Medicine, Tel-Aviv University, Israel.
authors.forename: D G
authors.initials: DG
authors.lastname: Ohad
authors.forename: Z
authors.initials: Z
authors.lastname: Vered
authors.forename: R
authors.initials: R
authors.lastname: Caminker
authors.forename: M
authors.initials: M
authors.lastname: Eldar
mesh_terms: D000818:Animals; D006328:Cardiac Catheterization / Q000295:instrumentation; D017115:Catheter Ablation; D004452:Echocardiography; D005260:Female; D005471:Fluoroscopy; D006352:Heart Ventricles / Q000000981:diagnostic imaging; D006439:Hemodynamics; D015641:Radiography, Interventional; D013552:Swine; D017180:Tachycardia, Ventricular / Q000000981:diagnostic imaging* / Q000503:physiopathology / Q000601:surgery*; D016277:Ventricular Function, Left