Current Density Mapping of the In Vivo Swine Heart using Multichannel Acoustoelectric Cardiac Imaging

Cardiac arrhythmias are caused by irregular activation in the heart. When pharmaceutical therapy fails, severe arrythmias are often treated with radiofrequency ablation. Existing methods to map electrical activation in the heart have poor spatial resolution or are invasive. We proposed Acoustoelectric Cardiac Imaging (ACI) to achieve non-invasive mapping of cardiac electrical activities with mm resolution. In this study, we used simulations to develop a reconstruction method for generating current density map from multi-channel ACI signals, and applied it to in-vivo ACI data from a swine heart with a resolution less than 5mm. With 5 leads at SNR from 55 to 80, the five differential signals could be combined in simulation to reconstruct the source current density map, with a correlation coefficient ≈ 0.74 for the x-component. For in-vivo data, we find that singular values decomposition provides a criterion for reconstruction.