Please use this identifier to cite or link to this item:
https://ptsldigital.ukm.my/jspui/handle/123456789/487275
Title: | Predictive model for the assessment of high-risk atherosclerosis using photoplethysmography |
Authors: | Yousef Kamel Qawqzeh (P46820) |
Supervisor: | Md. Mamun Ibne Reaz, Associate Professor Dr. |
Keywords: | Predictive model Assessment of high-risk atherosclerosis High-risk atherosclerosis Photoplethysmography Atherosclerosis |
Issue Date: | 17-Oct-2011 |
Description: | Cardiovascular diseases (CVD) are the principal causes of death world-wide. Stiffening of the arterial wall is normally associated with the beginning, or the progression of atherosclerosis. As changes can be detected before the appearance of clinically apparent vascular disease, arterial stiffness may act either as a marker for the development of future atherosclerotic disease, or may be more directly involved in the process of atherosclerosis. Atherosclerosis plays an important role in the loss of the elastic properties of arteries walls, thereby, raises the chance of developing a vascular disease. Atherosclerosis can be measured by carotid intima-media thickness (CIMT) technique. CIMT test uses ultrasound technology to measure the thickness of the first two layers of the carotid artery located in the neck, where blood-flow-blocking plaque first develops. Thickness of the artery wall is an early indicator of vascular disease. The main disadvantages of CIMT technique are that it is costly, operator dependent and it causes discomfort to the patient (15-20 minutes procedure). The main objective of this work is to evaluate the potential use of Photoplethysmogram (PPG), a noninvasive optoelectronic method for measuring and recording changes of blood volume, routinely utilize in a clinical setup, to assist CIMT in the prediction of highrisk atherosclerosis. PPG signals and CIMT were in-parallel recorded from a sample of erectile dysfunction subjects (80 subjects). The carotid intima-media thicknesses were screened from both left and right neck side. PPG signals were acquired from index fingers of the right arm and left arm at a rate of 5500 Hz. Standard signal processing techniques, detrending, band pass filtering, resampling, and normalization and a customized algorithm for peaks detection were applied off-line. CIMT data were recorded into a new index called high-risk atherosclerosis (HRART), which represents the presence or the absence of high-risk atherosclerosis. A statistical model by means of logistic regression was developed to predict the atherosclerosis by means of b/a index from PPG signal, pulse pressure (PP) and subject's height. From statistical analysis, the findings of the research as follows: (i)The model showed a sensitivity of 76.5% in the prediction of true-positive cases (TP), (ii) The model showed a specificity of 64.7 in the prediction of true-negative cases (TN), (iii) Backward logistic regression showed better results compared to forward logistic regression, since Nagelkerke R-square were 0.288 and 0.372 respectively, and (iv) PPG (b/a) index, PP and subject's height were the main factors of the developed model. The results show that the proposed model is a potentially promising tool for the assessment of arterial stiffness, applicable to noninvasive and rapid assessment of atherosclerosis as a low cost, operator independent and ease of use measure compared to CIMT. In addition, the proposed technique can be used as alternative rapid measure of high-risk atherosclerosis which is a sign of developing CVD and erectile dysfunction.,PhD |
Pages: | 125 |
Call Number: | RC692 .Q339 2011 3 |
Publisher: | UKM, Bangi |
Appears in Collections: | Faculty of Engineering and Built Environment / Fakulti Kejuruteraan dan Alam Bina |
Files in This Item:
File | Description | Size | Format | |
---|---|---|---|---|
ukmvital_74887+Source01+Source010.PDF Restricted Access | 3.54 MB | Adobe PDF | View/Open |
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.