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

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.

Preliminary study a non-invasion method on early cardiac energy defect based on Hilbert Huang Transform.

Statistics released by the World Health Organization in 2018 show that the total death of people is 56.9 million worldwide in 2016. The first one is cardiovascular diseases, including ischemic heart disease and stroke, which accounted for 17.65 million people (31%) [1]. Treadmill Exercise Test is suitable for measuring the changes in Electrocardiography (ECG) initial, middle, and after exercise [2]. They are using it to distinguish chest pain without apparent causes, judging the severity of coronary artery disease, and screening personnel with coronary artery disease risk factors. The most important contribution of this study is to use the Hilbert Huang Transform (HHT) [3], a non-invasive method, to decompose the original ECG signals of inspectors through the Empirical Mode Decomposition (EMD) [4-7], not the commonly used of 12-lead ECG detection method. There is a total of 49 participants in 24 pseudo-positive persons; 4 were re-judged into positive, reducing 83.3% pseudo-positive persons who need to do the follow-up testing, significantly reducing the consumption of medical and time.

[Investigation of surgical - orthodontic treatment of dentigerous cysts in 19 children and adolescents].

PURPOSE: To evaluate the therapeutic effect of dentigerous cysts in children and adolescents with surgical windowing and orthodontic traction. METHODS: A total of 19 cases were collected from the First People 's Hospital of Yongkang between 2014 to 2016. All cases were treated with surgical windowing and orthodontic traction. During the operation, fenestration was made to remove part of the cyst wall; full expose the tooth surface for adhesion, attach orthodontic traction attachments, reposition the mucosal flap and suture, and then start orthodontic treatment to guide teeth eruption for 1-2 months. RESULTS: After treatment, the cysts were gradually decreased until disappeared. The teeth successfully reached the normal occlusal position; all erupted teeth have health periodontal tissues, normal pulp vitality, and good root morphology. CONCLUSIONS: Use of surgical windowing and orthodontic traction to treat dentigerous cysts in children and adolescents can achieve good clinical effect, which provides a new treatment method.