Inverse localization of ischemia in a 3D realistic geometry: A level set approach

Abstract

The reconstruction of cardiac ischemic regions from body surface potential measurements (BSPMs) is usually performed at a single time instant which corresponds to the plateau or resting phase of the cardiac action potential. Using a different approach, we previously proposed a level set formulation that incorporates the knowledge of the cardiac excitation process in the inverse procedure, thus exploiting the spatio-temporal correlations contained in the BSPMs. In this study, we extend our inverse levelset formulation for the reconstruction of ischemic regions to 3D realistic geometries, and analyze its performance in different noisy scenarios. Our method is benchmarked against zero-order Tikhonov regularization. The inverse reconstruction of the ischemic region is evaluated using the correlation coefficient (CC), the sensitive error ratio (SN), and the specificity error ratio (SP). Our algorithm outperforms zero-order Tikhonov regularization, specially in highly noisy scenarios.

Stability results for the parameter identification inverse problem in cardiac electrophysiology

“…The parameter t in in both studies plays an important role in estimating the velocity of the electrical wave. The monodomain equation combined with the Mitchell-Schaeffer ionic model has also been used for detecting the ischemia region using an adjoint approach combined with a level set method in two-dimensional and three-dimensional frameworks [1,14]. In these works a low value of the parameter t in has been identified to be one of the major characteristics of the ischemic region.…”