Electrodynamic Heart Model Construction and ECG Simulation

L. Xia; M. Huo; Q. Wei; F. Liu; S. Crozier

doi:10.1055/s-0038-1634119

Methods of Information in Medicine, Table of Contents

Methods Inf Med 2006; 45(05): 564-573
DOI: 10.1055/s-0038-1634119

Original Article

Schattauer GmbH

Electrodynamic Heart Model Construction and ECG Simulation

Authors

L. Xia

¹Department of Biomedical Engineering, Zhejiang University, Hangzhou, China
M. Huo

²Department of Computer Science, Zhejiang University City College, Hangzhou, China
Q. Wei

³The School of Information Technology and Electrical Engineering, The University of Queensland, Queensland, Australia
F. Liu

¹Department of Biomedical Engineering, Zhejiang University, Hangzhou, China

³The School of Information Technology and Electrical Engineering, The University of Queensland, Queensland, Australia
S. Crozier

³The School of Information Technology and Electrical Engineering, The University of Queensland, Queensland, Australia

Abstract

Summary

Objectives: In this paper, we present a unified electrodynamic heart model that permits simulations of the body surface potentials generated by the heart in motion. The inclusion of motion in the heart model significantly improves the accuracy of the simulated body surface potentials and therefore also the 12-lead ECG.

Methods: The key step is to construct an electromechanical heart model. The cardiac excitation propagation is simulated by an electrical heart model, and the resulting cardiac active forces are used to calculate the ventricular wall motion based on a mechanical model. The source-field point relative position changes during heart systole and diastole. These can be obtained, and then used to calculate body surface ECG based on the electrical heart-torso model.

Results: An electromechanical biventricular heart model is constructed and a standard 12-lead ECG is simulated. Compared with a simulated ECG based on the static electrical heart model, the simulated ECG based on the dynamic heart model is more accordant with a clinically recorded ECG, especially for the ST segment and T wave of a V1-V6 lead ECG. For slight-degree myocardial ischemia ECG simulation, the ST segment and T wave changes can be observed from the simulated ECG based on a dynamic heart model, while the ST segment and T wave of simulated ECG based on a static heart model is almost unchanged when compared with a normal ECG.

Conclusions: This study confirms the importance of the mechanical factor in the ECG simulation. The dynamic heart model could provide more accurate ECG simulation, especially for myocardial ischemia or infarction simulation, since the main ECG changes occur at the ST segment and T wave, which correspond with cardiac systole and diastole phases.

Keywords

Electromechanical heart model - finite element method - electrocardiogram - myocardial ischemia

Full Text

References

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