Early detection of myocardial ischemia in resting ECG: analysis by HHT

• Published in: Biomedical engineering online Vol. 22; no. 1; pp. 23 - 14
• Main Authors: Wang, Chun-Lin, Wei, Chiu-Chi, Tsai, Cheng-Ting, Lee, Ying-Hsiang, Liu, Lawrence Yu-Min, Chen, Kang-Ying, Lin, Yu-Jen, Lin, Po-Lin
• Format: Journal Article
• Language: English
• Published: London BioMed Central 10.03.2023; BioMed Central Ltd; Springer Nature B.V; BMC
• Subjects: Accuracy; Algorithms; Analysis; Angina; Angina pectoris; Biomaterials; Biomedical Engineering and Bioengineering; Biomedical Engineering/Biotechnology; Biotechnology; Cardiac arrhythmia; Cardiovascular disease; Complications and side effects; Constriction, Pathologic; Coronary Artery Disease; Coronary Stenosis - diagnosis; Defects; Demographic aspects; Diagnosis; EKG; Electrocardiography; Energy; Engineering; Exercise electrocardiography; Exercise Test; Exercise tests; Heart failure; Hilbert–Huang transform; Humans; Ischemia; Muscle contraction; Myocardial energy; Myocardial ischemia; Myocardial Ischemia - diagnosis; Patients; Power spectral density; Risk factors; Taiwan; Power spectral density; Hilbert–Huang transform; Exercise electrocardiography; Myocardial energy
• ISSN: 1475-925X; 1475-925X
• DOI: 10.1186/s12938-023-01089-9

Background Exercise electrocardiography (ECG) is a noninvasive test aiming at producing ischemic changes. However, resting ECG cannot be adopted in diagnosing myocardial ischemia till ST-segment depressions. Therefore, this study aimed to detect myocardial energy defects in resting ECG using the Hilbert–Huang transformation (HHT) in patients with angina pectoris. Methods Electrocardiographic recordings of positive exercise ECG by performing coronary imaging test (n = 26) and negative exercise ECG (n = 47) were collected. Based on the coronary stenoses severity, patients were divided into three categories: normal, < 50%, and ≥ 50%. During the resting phase of the exercise ECG, all 10-s ECG signals are decomposed by HHT. The RT intensity index, composed of the power spectral density of the P, QRS, and T components, is used to estimate the myocardial energy defect. Results After analyzing the resting ECG using HHT, the RT intensity index was significantly higher in patients with positive exercise ECG (27.96%) than in those with negative exercise ECG (22.30%) (p < 0.001). In patients with positive exercise ECG, the RT intensity index was gradually increasing with the severity of coronary stenoses: 25.25% (normal, n = 4), 27.14% (stenoses < 50%, n = 14), and 30.75% (stenoses ≥ 50%, n = 8). The RT intensity index of different coronary stenoses was significantly higher in patients with negative exercise ECG, except for the normal coronary imaging test. Conclusions Patients with coronary stenoses had a higher RT index at the resting stage of exercise ECG. Resting ECG analyzed using HHT could be a method for the early detection of myocardial ischemia.