Automated Framework for the Inclusion of a His–Purkinje System in Cardiac Digital Twins of Ventricular Electrophysiology

Abstract

Personalized models of cardiac electrophysiology (EP) that match clinical observation with high fidelity, referred to as cardiac digital twins (CDTs), show promise as a tool for tailoring cardiac precision therapies. Building CDTs of cardiac EP relies on the ability of models to replicate the ventricular activation sequence under a broad range of conditions. Of pivotal importance is the His–Purkinje system (HPS) within the ventricles. Workflows for the generation and incorporation of HPS models are needed for use in cardiac digital twinning pipelines that aim to minimize the misfit between model predictions and clinical data such as the 12 lead electrocardiogram (ECG). We thus develop an automated two stage approach for HPS personalization. A fascicular-based model is first introduced that modulates the endocardial Purkinje network. Only emergent features of sites of earliest activation within the ventricular myocardium and a fast-conducting sub-endocardial layer are accounted for. It is then replaced by a topologically realistic Purkinje-based representation of the HPS. Feasibility of the approach is demonstrated. Equivalence between both HPS model representations is investigated by comparing activation patterns and 12 lead ECGs under both sinus rhythm and right-ventricular apical pacing. Predominant ECG morphology is preserved by both HPS models under sinus conditions, but elucidates differences during pacing.

A personalized real-time virtual model of whole heart electrophysiology

“…Body surface potential maps and electro-anatomical maps, as well as cardiac sources, needed in various clinical applications, could be computed using reaction-Eikonal in pseudo-bidomain mode in approximately 35 min on a normal desktop machine with 8 cores. Validation of the underlying simulation in previous work reported in Gillette et al, 2021(Gillette et al, 2021a showed that ECGs acquired using the reaction-Eikonal method paired with lead fields gave comparable ECG morphologies to a traditional high-resolution, full bidomain simulation at a fraction of the costs. Such finedetailed full bidomain simulations on even a simpler biventricular setup without a physiologically-detailed His-Purkinje system lasting only 150 ms, required 30 min min on a HPC with 240 computing cores to compute both cardiac sources and potentials used to generate the same 12 lead ECG (Gillette et al, 2021a).…”

Comparison between conduction system pacing and cardiac resynchronization therapy in right bundle branch block patients

“…Table 1 presents the patient cohort demographics, the LV, RV volume, and LV diameter derived from the mesh as described in ( Strocchi et al, 2020a ). A His-Purkinje network accounting for three LV fascicles (anterior and posterior, which further branches into two septal fascicles) and two RV fascicles (one septal fascicle and the moderator band) was generated for each mesh as described previously ( Gillette et al, 2021 ; Gillette et al, 2022 ). In the Supplement, we provide additional details about the construction of the His-Purkinje networks.…”

How synergy between mechanistic and statistical models is impacting research in atrial fibrillation

“…Developing a personalized digital twin of the heart, which integrates coherently and dynamically the patient’s clinical data over time, will likely be essential to overcome current challenges ( Corral-Acero et al, 2020 ; Lindemans, 2020 ; Gerach et al, 2021 ). Over the last decades, the digital twin heart has emerged as a modality to diagnose, understand and therapy complex arrhythmias ( Gillette et al, 2021a ; Gillette et al, 2021b ). This mini-review is structured as follows: Section 2 briefly summarizes the AF pathophysiology and current therapeutic modalities.…”