Spatial resolution of body surface potential and Laplacian pace mapping

The spatial resolution (SR) of the body surface Laplacian map (BSLM) was assessed using a three-dimensional, realistically shaped, heart-torso model. The BSLMs were estimated from the body surface potential maps (BSPMs) generated by pacing different sites of the ventricle of a three-dimensional computer heart model using a novel three-dimensional spline Laplacian algorithm. Pacing was performed at a total of 88 myocardial units in five regions of the AV ring (anterior, left wall, posterior, right wall, and septum) and three regions adjacent to the AV ring in the middle anterior and posterior of the ventricles. The SR of the BSPMs and BSLMs were investigated by means of the correlation coefficient (CC) of maps. When 5 μV and 10 μV Gaussian white noises were added into the simulated BSPMs, the SR, at 36 ms after the onset of pacing, was about 5.0 ± 1.2 mm and 5.4 ± 1.3 mm for the BSPMs, and 3.3 ± 0.8 mm and 4.0 ± 0.9 mm for the BSLMs, respectively. The results of the present simulation study suggest that the BSLM has higher SB and may provide a more accurate means than the BSPMs for differentiating between the accessory pathways or the sites of other ectopic cardiac beats along the AV ring and in its neighboring regions.