Estimation of heart-surface potentials using regularized multipole sources.
Direct inference of heart-surface potentials from body-surface potentials has been the goal of most recent work on electrocardiographic inverse solutions. We developed and tested indirect methods for inferring heart-surface potentials based on estimation of regularized multipole sources. Regularization was done using Tikhonov, constrained-least-squares, and multipole-truncation techniques. These multipole-equivalent methods (MEMs) were compared to the conventional mixed boundary-value method (BVM) in a realistic torso model with up to 20% noise added to body-surface potentials and +/-1 cm error in heart position and size. Optimal regularization was used for all inverse solutions. The relative error of inferred heart-surface potentials of the MEM was significantly less (p < 0.05) than that of the BVM using zeroth-order Tikhonov regularization in 10 of the 12 cases tested. These improvements occurred with a fourth-degree (24 coefficients) or smaller multipole moment. From these multipole coefficients, heart-surface potentials can be found at an unlimited number of heart-surface locations. Our indirect methods for estimating heart-surface potentials based on multipole inference appear to offer significant improvement over the conventional direct approach.
Beetner
Daryl G
DG
Department of Electrical and Computer Engineering, University of Missouri-Rolla, Rolla, MO 65401, USA. daryl@ece.umr.edu
Arthur
R Martin
RM
D000328:Adult; D000465:Algorithms; D018780:Body Surface Potential Mapping / Q000379:methods*; D003198:Computer Simulation; D004562:Electrocardiography / Q000379:methods; D006329:Heart Conduction System / Q000502:physiology*; D006801:Humans; D008297:Male; D008955:Models, Cardiovascular; D012680:Sensitivity and Specificity