The Influence of the Most Powerful Signals on the Pacing Site Localization by Single Dipole

In real experiments with body surface potential mapping, it is usual that the measuring electrodes cannot be placed regularly because of other patches of sensors used on the torso during the procedure. The influence of accidentally missing the most powerful ECG signals on the inverse localization of the pacing site using a single dipole was studied. Body surface potential maps from three tank experiments on the pig or dog heart and one measurement from the patient's torso were used for inverse computation of the known pacing site position using the full electrodes setup and setups omitting 10% and 20% of the signals with the largest power. The sensitivity of the inverse method was evaluated by localization error between the true and computed pacing site. The localization error did not change (13mm or 7mm) or changed from 13 to 24 mm for tank data, but it increased rapidly from 19 to 41/68 mm for human data. The largest effect of electrodes' omission using human data can be explained by the largest complexity of the human torso what is not fully included in the computational torso model.