Imaging and visualization of 3-D cardiac electric activity

Abstract

Abstract-Noninvasive imaging of cardiac electric activity is of importance for better understanding the underlying mechanisms and for aiding clinical diagnosis and intervention of cardiac abnormalities. We propose to image the three-dimensional (3-D) cardiac bioelectric source distribution from body-surface electrocardiograms. Cardiac electrical sources were modeled by a current dipole distribution throughout the entire myocardium, and estimated by using the Laplacian weighted minimum norm (LWMN) algorithm from body-surface potentials. The estimated inverse solution of the current distribution was further improved by using a recursive weighting strategy for localized sources, such as origins of cardiac arrhythmias. Computer simulations were conducted to test the feasibility of the proposed approach by using a 3-D ventricle model embedded in a realistically shaped torso model. The boundary element method was used to solve the forward problem from assumed cardiac sources to the body-surface potentials. Two testing dipoles were placed in the left and right ventricles, simulating the early activation associated with ventricular arrhythmias. The LWMN inverse solution showed an equivalent source distribution over the entity of both ventricles, with spread areas of activity overlying the positions of the testing dipoles. The sharpened inverse image provides well-localized focal sources near the testing dipole positions. In summary, the present computer simulation suggests that the proposed 3-D cardiac current source imaging and localization approach appears to be a promising candidate for localizing and imaging sites of origins of cardiac activation.

Noninvasive imaging of three-dimensional cardiac activation sequence during pacing and ventricular tachycardia

“…16,17,18 Recently, an alternative 3-D cardiac electrical imaging (3-DCEI) approach has been proposed to image ventricular activation sequence from the inversely reconstructed equivalent current densities (ECDs). 19,20 A feasibility study 21 in the rabbit heart showed the potential application of this 3-DCEI approach in localizing the origin of activation and imaging activation sequence under single-site pacing.…”

Electrocardiologic and related methods of non-invasive detection and risk stratification in myocardial ischemia: state of the art and perspectives

“…He and Wu developed novel electrocardiographic tomography techniques to image cardiac current density distributions within the myocardium [89]. A realistic geometry inhomogeneous heart-torso model based on tomographic imaging was used to localize the site of origin of cardiac activation, show the cardiac activation sequence and image the transmembrane potential distribution within the 3D anisotropic myocardium.…”

Noninvasive Imaging of High-Frequency Drivers and Reconstruction of Global Dominant Frequency Maps in Patients With Paroxysmal and Persistent Atrial Fibrillation

“…Due to the very thin nature of atria over most areas, such approximation is deemed appropriate and supported by our promising clinical results. In a more accurate source model, one would need to account for the volume nature of atria by expanding the 2D atrial surface current density source model to a 3D atrial current density source model (see [7]–[13], e.g. ).…”