title: Microwave catheter design.
abstract: A microwave antenna system for transcatheter ablation of cardiac tissue is investigated. A numerical model based on the finite-difference time-domain method incorporating a Gaussian pulse excitation has been constructed and frequency domain electric and magnetic fields are obtained through Fourier transformation. Results are presented for a coaxial line fed monopole catheter which is modified by the successive inclusion of a Teflon sheath outer coating, a terminating disk at the tip of the antenna, a sleeve choke, and a high dielectric constant cylinder surrounding the monopole antenna. The effects of these design features are characterized in terms of specific absorption rate (SAR) and return loss (RL). Numerical calculations are confirmed by comparing with the RL measurement of a Teflon-coated monopole containing a disk and choke.
authors.affiliation: Department of Electrical Engineering, Texas A&M University, College Station 77843, USA. nevels@ee.tamu.edu
authors.forename: R D
authors.initials: RD
authors.lastname: Nevels
authors.forename: G D
authors.initials: GD
authors.lastname: Arndt
authors.forename: G W
authors.initials: GW
authors.lastname: Raffoul
authors.forename: J R
authors.initials: JR
authors.lastname: Carl
authors.forename: A
authors.initials: A
authors.lastname: Pacifico
mesh_terms: D000818:Animals; D001145:Arrhythmias, Cardiac / Q000601:surgery; D001672:Biocompatible Materials; D017115:Catheter Ablation / Q000295:instrumentation*; D017097:Electric Impedance; D004566:Electrodes; D004867:Equipment Design; D005583:Fourier Analysis; D006801:Humans; D008422:Materials Testing; D008872:Microwaves / Q000627:therapeutic use*; D008954:Models, Biological; D011138:Polytetrafluoroethylene; D013696:Temperature
chemical_list: D001672:Biocompatible Materials; D011138:Polytetrafluoroethylene