The inverse problem of electrocardiology: the performance of inversion techniques as a function of patient anatomy.

Sixteen anatomically correct bodies have been studied to determine the performance of the inversion techniques of zero-order Tikhonov regularization and singular value decomposition. The bodies have varying heart height and diameter, thickness of subcutaneous fat layer, and distance of the heart from the left wall of the chest. Comparisons are made in terms of trade-off curves for noise amplification factor and spread of epicardial potentials. It was found that regularization performs better than singular value decomposition on all bodies; the larger the heart size, the more reliable the results; and for a given heart size, the thinner the subcutaneous fat layer, the more reliable the results. The distance of the heart from left wall of the chest was found to be a less significant factor for a given heart size.