Validation and Opportunities of Electrocardiographic Imaging: From Technical Achievements to Clinical Applications

Abstract

Electrocardiographic imaging (ECGI) reconstructs the electrical activity of the heart from a dense array of body-surface electrocardiograms and a patient-specific heart-torso geometry. Depending on how it is formulated, ECGI allows the reconstruction of the activation and recovery sequence of the heart, the origin of premature beats or tachycardia, the anchors/hotspots of re-entrant arrhythmias and other electrophysiological quantities of interest. Importantly, these quantities are directly and non-invasively reconstructed in a digitized model of the patient’s three-dimensional heart, which has led to clinical interest in ECGI’s ability to personalize diagnosis and guide therapy. Despite considerable development over the last decades, validation of ECGI is challenging. Firstly, results depend considerably on implementation choices, which are necessary to deal with ECGI’s ill-posed character. Secondly, it is challenging to obtain (invasive) ground truth data of high quality. In this review, we discuss the current status of ECGI validation as well as the major challenges remaining for complete adoption of ECGI in clinical practice. Specifically, showing clinical benefit is essential for the adoption of ECGI. Such benefit may lie in patient outcome improvement, workflow improvement, or cost reduction. Future studies should focus on these aspects to achieve broad adoption of ECGI, but only after the technical challenges have been solved for that specific application/pathology. We propose ‘best’ practices for technical validation and highlight collaborative efforts recently organized in this field. Continued interaction between engineers, basic scientists, and physicians remains essential to find a hybrid between technical achievements, pathological mechanisms insights, and clinical benefit, to evolve this powerful technique toward a useful role in clinical practice.

Impact of Decreased Transmural Conduction Velocity on the Function of the Human Left Ventricle: A Simulation Study

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Multiobjective Optimization Approach to Localization of Ectopic Beats by Single Dipole: Case Study

“…Body surface potentials mapping lasting several minutes was performed on the male patient (age 57) with cardiostimulator and suffering by premature ventricular contractions (PVC). ECG signals were recorded in three modes of the cardiostimulator function: (1) cardiostimulator worked in the usual setting of patient's everyday life, (2) no cardiostimulator intervention and (3) an electrode implanted in the right ventricle near apex was paced with the frequency of 100 beats per minute. The measurements were carried out in cooperation with The National Institute for Cardiovascular Diseases in Bratislava on the ProCardio8 system developed in our laboratory [5] using 128 electrodes in 16 strips placed regularly on the patient's torso.…”

“…In general, ECGI aims to reconstruct the heart electrical activity on the whole surface of ventricles during the heartbeat. The attempts of several research groups were summarized recently in [2]. Because the inverse problem is ill-posed its solution requires some form of regularization, selection of which is one of the specific tasks of the problem [3].…”

Mechanisms of Arrhythmogenicity in Hypertrophic Cardiomyopathy: Insight From Non-invasive Electrocardiographic Imaging

“…In this study, we used the Forward/Inverse problem toolkit from the SCIRun problem-solving environment, which is used by many investigators in the field (Burton et al, 2011;Coll-Font et al, 2014;Cluitmans et al, 2018;Wang et al, 2018). However, knowing the limitations of the ECGi method (Duchateau et al, 2019), we intentionally limited our analysis by averaged "per segment" data.…”