A Volumetric ECGI Approach for Regular Rhythms

Jorge Vicente Puig1, Judit Chamorro-Servent1, Ernesto Zacur2, Ines Llorente3, Marta Martínez Pérez4, Jorge Sanchez5, Jana Reventós Presmanes6, Ivo Roca Luque7, Lluis Mont7, Felipe Atienza8, Maria de la Salud Guillem Sánchez3, Andreu M. Climent3, Ismael Hernández-Romero9
1Universitat Autònoma de Barcelona, 2CorifyCare S.L., 3Universitat Politècnica de València, 4COR-Group, ITACA Institute, Universitat Politècnica de València, Valencia, Spain, 5Centro de Investigacion e Innovacion en Bioingenieria (Ci2B), Universidad Politecnica de Valencia, 6Arrhythmias Department, Hospital Clínic de Barcelona, 7Institut Clínic Cardiovascular, Hospital Clínic de Barcelona, Catalonia, Spain, 8Hospital General Universitario Gregorio Marañón (Cardiology Department), 9ITACA Institute, Universitat Politècnica de València


Abstract

Introduction: Standard ECGI methods estimate epicardial potentials, which limits their applicability in clinically relevant scenarios, particularly when arrhythmogenic substrates are located intramurally or endocardially. Methodology: We propose a novel ECGI methodology for estimating volumetric cardiac sources. Using Green's functions, the approach establishes a direct and physiologically consistent link between internal sources and body surface measurements. To assess its performance, the method is compared to classical epicardial ECGI in three simulations of premature ventricular ectopic beats, evaluating local activation time maps. Its clinical applicability is further explored through tests on three patients with distinct arrhythmic conditions. Results: The Euclidean distance between the estimated and simulated origins of activation is reduced with the volumetric method from 25.50mm ±3.96mm to 12.26mm ±0.79mm. Additionally, epicardial ECGI shows a high amplitude ratio (51 : 1) between epicardium and endocardium, indicating poor depth accuracy. Volumetric ECGI shows a lower ratio (1.64 : 1), suggesting a more physiologically reconstruction across the myocardial wall. Patient results show strong concordance with electroanatomical maps and 12-lead ECGs, supporting the method's potential for clinical use. Conclusions: These results indicate that the proposed approach enables the estimation of 3D cardiac sources in both simulated and clinical scenarios.