SOLVING THE INVERSE PROBLEM OF ELECTROCARDIOGRAPHY FOR SPONTANEOUS PVC LOCALIZATION: ANALYSIS OF CLINICAL ELECTROCARDIOGRAPHIC DATA

2023-1-27
Rasoolzadeh, Nika
The inverse problem of electrocardiography refers to the determination of the electrical activity of the heart from the body surface potential measurements (BSPM). Knowledge of the electrical activity state of the heart can provide valuable insights for the diagnosis of cardiac disorders and aid in the facilitation of the development of appropriate treatments. Consequently, efficient resolution of this problem has the potential to be of significant benefit to clinical practices, making it imperative to continue the research in this field. This problem is considered ill-posed due to the presence of attenuation and spatial averaging effects within the thorax between the cardiac sources and the body surface. This characteristic can result in highly inaccurate or oscillatory solutions, particularly in the presence of measurement noise or an imprecise mathematical model. Despite significant efforts to address the challenges and limitations, an optimal method for the analysis of clinical data in this problem has yet to be developed. A relatively limited number of studies have been conducted on the application of inverse problem of electrocardiography for the localization of spontaneous Premature Ventricular Contraction (PVC). PVCs refer to abnormal cardiac contractions that originate from one of the ventricles. This study focuses on using Tikhonov regularization method for reconstruction of unknown heart potentials with respect to various torso volume and cardiac source models derived from BSPMs of patients who have been indicated for ablation. By estimating Activation Time (AT) sequences, the PVC origin locations are explored for a number of patients. The findings indicate that the implementation of the proposed methods could provide physicians with a more accurate localization of spontaneous PVCs.

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Citation Formats
N. Rasoolzadeh, “SOLVING THE INVERSE PROBLEM OF ELECTROCARDIOGRAPHY FOR SPONTANEOUS PVC LOCALIZATION: ANALYSIS OF CLINICAL ELECTROCARDIOGRAPHIC DATA,” M.S. - Master of Science, Middle East Technical University, 2023.