title: Estimates of endocardial potentials from non-contact intracavitary probes.
abstract: The EnSitetrade intracavitary probe system developed by Endocardial Solutions, Inc (St. Jude Medical, St. Paul, MN) was used to simultaneously record geometric information, probe potentials, and selected endocardial potentials within the right atria for four patients. Tikhonov regularization was then used to estimate endocardial potentials from probe measurements for each patient at each endocardial site. The correlation coefficients and relative errors between the estimated potentials and the measured endocardial potentials were then calculated. This inverse problem was quite ill-conditioned, and first-order Tikhonov regularization performed better than zero-order or second-order Tikhonov regularization in producing stable and accurate results. In choosing the regularization parameter micro, a constant value of micro=0.3 performed as well as CRESO and maximum curvature, which pick a different micro for each time instant.
authors.affiliation: Dept. of Electr. Eng., Rose-Hulman Inst. of Technol., Terre Haute, IN 47803, USA. robert.throne@rose-hulman.edu
authors.forename: Robert
authors.initials: R
authors.lastname: Throne
authors.forename: Lorraine
authors.initials: L
authors.lastname: Olson
authors.forename: John
authors.initials: J
authors.lastname: Windle
authors.forename: Jeff
authors.initials: J
authors.lastname: Schweitzer
authors.forename: Eric
authors.initials: E
authors.lastname: Voth
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000465:Algorithms; D018780:Body Surface Potential Mapping / Q000295:instrumentation* / Q000379:methods; D003198:Computer Simulation; D003936:Diagnosis, Computer-Assisted / Q000295:instrumentation / Q000379:methods; D004562:Electrocardiography / Q000295:instrumentation* / Q000379:methods; D004574:Electromagnetic Fields; D004699:Endocardium / Q000502:physiology*; D006329:Heart Conduction System / Q000502:physiology*; D006801:Humans; D008955:Models, Cardiovascular; D011829:Radiation Dosage; D011874:Radiometry / Q000379:methods*