利用光電容積脈搏波信號分析及診斷心臟血管疾病

The Analysis and Diagnosis of Cardiovascular System by Photoplethysmography

陳啟彬(Chi-Bian Chen)

指導教授 ： 范憶華

中原大學/工學院/機械工程研究所/碩士(2008年)

https://doi.org/10.6840/cycu200800272

摘要

本論文以一創新的方式利用雙通道同步量測手指與腳趾的容積波，進行受測者脈波傳導速度(Pulse Wave Velocity，PWV)的非侵入式量測。主要採用雙通道技術同步收集手指與腳趾的數位容積波
(Digital Volume Pulse, DVP)，並利用PC 端之軟體即時計算出脈波傳導速率(Pulse wave Velocity, PWV)和其他相關脈波特徵值的分析及研究，藉此提供醫師判斷動脈硬化之程度。目前市面上量測系統採單點分時之擷取方式存在諸多缺點，因而嘗試開發以雙通道同步擷取技術為基礎的即時處理系統，以期獲得較高之準確度和降低操作複雜度。另外，在脈波轉折點(Foot of the wave)定位方面，本系統不需藉由外部心電圖(Electrocardiogram, ECG)進行輔助定位，而是改採以自行開發之軟體演算法進行處理。本論文研製之完整系統主要組成包括自行研發紅外線感測器電路、類比訊號處理電路以及PC 端之即時分析軟體，證實本系統為一準確度高且操作方便之人體動脈硬化程度量測儀器。
研究中，系統同時測量三通道生理訊號，其中心電訊號可獲得每位受測者之心律跳動(HR)，及心臟活動狀況、同步收集手指與腳趾的數位容積波(Digital Volume Pulse, DVP)，並利用PC端之軟體即時計算出脈波傳導速率(Pulse wave Velocity, PWV)和光電容積脈搏波結合心電訊號獲得脈波傳導速度(PWV)做比較，印證其可行性，光電容積脈搏波可獲得血管硬化指數(SI)、血管阻塞指數(RI)等資料，其中之HR、
PWV、SI、RI可進行心血管功能定量評估，光電容積脈搏波信號中亦包含了許多有價值的醫學訊息，試圖將光電容積脈搏波信號使用傅立葉轉換、小波轉換等不同的分析方法，找出和HR、PWV、SI、RI等資料的相關性，去獲得有用資訊並找出其所代表的醫學意涵，以利日後臨床診斷。
目前可用來非侵入性診斷心血管功能的方法各有利弊，存在有費用昂貴、操作複雜、理論依據不充分等諸多缺點。光電容積脈搏波描記法具有操作簡便、成本低等優點，有巨大的發展潛力。因此，本論文提出了應用同步量測手指與腳趾的容積波訊號評估心血管功能的方法。
本論文以整合光量測與電學分析的一體解決方案(Total Solution)，達到心血管功能居家自我監測的應用，並且量測機制簡便，所以於居家儀器中極具發展潛力。

關鍵字

光電容積脈搏波 ； 血管硬化指數 ； 心血管疾病 ； 心電圖 ； 脈波傳導速度 ； 血管阻塞指數

並列摘要

The purpose of this thesis is to implement a non-invasivemeasurement system that can be used to collect the digital volume pulse(DVP) from a finger and a toe simultaneously with penetration infraredsensors. From the DVP data, the pulse wave velocity (PWV) can becalculated in real-time by using a personal computer (PC) for doctors todetermine the level of arterial stiffness of the patients. Although there are
some drawbacks to using a dual channel system (versus the commonly used single channel), the system proposed in this paper uses real-time processing with better accuracy and reduced complexity. Our software algorithm locates the characteristic point (foot of the pulse wave) without assistance from an electrocardiogram (ECG).The complete system includes: the circuits of the infrared sensor, analog signal processing
circuits and real-time analysis software based on a PC. The clinical results have shown that the proposed system can be operated easily to determine arterial stiffness with high accuracy.
This system could measure real-time PPG signal and ECG signal simultaneously. When combine with PPG signal and ECG signal, we can go deep to analyze cardiovascular parameters. In this study, we use three channel signal-- finger PPG, toe PPG and ECG signals to obtain every subject’s Heart Rate (HR),,Pulse Wave velocity (PWV), vascular stiffness index (SI), vascular reflection index (RI). Through HR, PWV, SI and RI parameter, we can estimate cardiovascular conditions. With PPG parameter, we can estimate
cardiopulmonary function. The study also discussed the relationships between age and cardiovascular physiology functions based on statistics. Now the non-invasive ways have both advantages and disadvantages, and they are expensive, complex and lack of theory. The
photoplethysmography is simple and cheap, it has great potential. So we use digital volume pulse (DVP) to assess large arterial stiffness .It
measures arterial stiffness by analyzing contour of DVP .The aim of the article is testing its feasibility. This paper brings up the total solution of integrating optical measurements with electrical analysis to achieve the goal of home cardiovascular function monitoring. The development of this system has great potential in home care.

並列關鍵字

Cardiovascular ； ECG ； SI ； PWV ； PPG ； RI

參考文獻

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