On the estimation of the Laplacian electrocardiogram during ventricular activation

Body surface Laplacian electrocardiogram (ECG) mapping using a set of disk electrodes is explored by both computer simulation and human experiments in 12 healthy subjects. The Laplacian ECG was estimated from body surface pot entials using finite difference estimation algorithms. The performance of t he finite difference Laplacian estimators was evaluated by both computer si mulation and human experiments. The present experimental results show that the two types of finite difference Laplacian estimates are highly correlate d and have a consistent spatial distribution over the anterolateral chest d uring normal ventricular activation. The present computer simulation and hu man experiment results suggest the feasibility of estimating the body surfa ce Laplacian maps (BSLMs) from potentials using the finite difference algor ithm over the anterior chest in male subjects. The noise levels of the BSLM s over the anterolateral chest were quantitatively compared to the noise le vels in corresponding body surface potential maps (BSPMs) in 12 healthy sub jects. The simulation and experiment results indicate that the noise to sig nal ratios in the BSLMs over the anterolateral chest during ventricular act ivation is about 5 times that of the BSPMs, when no signal processing is pe rformed. (C) 1999 Biomedical Engineering Society. [S0090-6964(99)00206-4].