- 學位論文
結合紅外線脈波及心電圖於心血管參數之探討及臨床應用
The Investigation and Clinical Applications of Cardiovascular Parameters by Integration of Infrared Pulse Signal and Electrocardiogram
摘要
本研究之目的最主要為發展一套結合紅外線脈波以及心電圖之心血管與脈波參數量測分析系統，並利用此系統來比較高血壓患者與正常人之各心血管與脈波參數，藉此得知以紅外線配合心電訊號之量測方式是否可以在各特徵參數中觀察到其差異性而確切反映出受測者之心血管狀態，並對其做出探討。 在系統方面，利用紅外線之光體積變化描記圖原理以及心電圖之即時量測，可擷取到人體之脈波訊號與心電訊號，並經由電腦端之紀錄介面來做生理訊號之儲存。在訊號處理方面，藉由自行撰寫之圖形化使用者介面，可自動計算出各心血管與脈波參數，而本研究亦使用改良型式之Gamma Density Function數學模型對擷取到之脈波訊號做曲線擬合以分離脈波成分，並得出額外可供分析之脈波參數。在實驗方面，本研究共蒐集15名高血壓病患和15名健康成年人，以心血管與脈波參數量測儀測量其脈波與心電訊號，並利用Matlab軟體所撰寫的訊號分析與參數擷取介面，自動擷取出所需要之特徵參數，而後再透過t-test分析找出高血壓患者與正常人間之差異性。 結果顯示，在儀器之訊號擷取與訊號分析上，可有效擷取出各參數值，而以改良型式之Gamma Density Function對脈波訊號做擬合時，對於擬合參數之客觀性以及擬合時之邊界設定均有所幫助。在臨床測試方面，可觀察到高血壓患者在脈波參數之統計上與正常人相比有較高之主波峰角(∠P、∠P1、∠P2)、主波峰時間(TP)、主波峰時間與脈波週期比(TP/T)、主波峰寬度(W)、主波峰寬度與脈波週期比(W/T)，以及較低之始射角(∠U)、重搏波時間與脈波週期比(TD/T)；在心血管相關參數之統計上則有較高之血管反射指數(RI)、血管硬化指數(SI)、脈波傳導速度(PWV)、心律變異度之低高頻功率面積比(LF/HF)，以及較低之脈波傳導時間(PTT)；在Gamma Density Function擬合參數之統計上則有較低之擬合參數(β1)、重搏波時間位移(t)、重搏波時間位移與脈波週期比(t/T)。而針對上述各參數來討論，皆可推測得知受測者其心血管狀態之不同，證實結合紅外線脈波以及心電訊號量測，在心血管居家自我監測方面之應用是具有可行性的。
並列摘要
The purpose of this research was to develop a cardiovascular and pulse parameters measurement and analysis system. In this study, we not only developed the system, but also compared the parameters and investigated the difference between hypertension patients and normal people. In the development of the system, we measured the real-time pulse signal and ECG signal simultaneously by the infrared rays photoplethysmography and electrocardiogram. With the data recording interface and graphical user interface, we could also acquire the cardiovascular and pulse parameters. By using the fixed gamma density function model, the pulse signal components could be separated and let us obtain additional gamma density function parameters for analysis. In the clinical experiment, fifteen hypertension patients and fifteen healthy adults without cardiovascular disease were recruited. We measured subjects’ pulse signal and ECG signal by the cardiovascular and pulse parameters measuring instrument, and used the signal analysis interface by Matlab to get the characteristic parameters. The study used t-test analysis to find the difference between hypertension patients and healthy adults. The results showed that the physiological parameters could be obtained effectively from human bodies by the instrument and signal analysis, and the fixed gamma density function could provide help for boundary setting and objectivity on the pulse curve fitting. In clinical observation about pulse parameters, we found that the hypertension patients had higher values in main pulse angle(∠P, ∠P1, ∠P2), main pulse time(TP), main pulse time to pulse period ratio(TP/T), main pulse wide(W), main pulse wide to pulse period ratio(W/T), and had lower values in upstroke angle(∠U), dicrotic pulse time to pulse period ratio(TD/T). In clinical observation about cardiovascular parameters, we found that the hypertension patients had higher values in reflection index(RI), stiffness index(SI), pulse wave velocity(PWV), low frequency to high frequency bands ratio in HRV(LF/HF), and had lower values in pulse transit time(PTT). Also, in clinical observation about gamma density function parameters, we found that the hypertension patients had lower values in fitting parameter(β1), dicrotic pulse shift(t), dicrotic pulse shift to pulse period ratio(t/T). With the above parameters, we could speculate the cardiovascular status of the subjects. Therefore, it was feasible to apply the combination of infrared rays pulse and electrocardiogram measurement for self-monitoring of cardiovascular functions.