Investigating properties of the cardiovascular system using innovative analysis algorithms based on ensemble empirical mode decomposition.
Cardiovascular system is known to be nonlinear and nonstationary. Traditional linear assessments algorithms of arterial stiffness and systemic resistance of cardiac system accompany the problem of nonstationary or inconvenience in practical applications. In this pilot study, two new assessment methods were developed: the first is ensemble empirical mode decomposition based reflection index (EEMD-RI) while the second is based on the phase shift between ECG and BP on cardiac oscillation. Both methods utilise the EEMD algorithm which is suitable for nonlinear and nonstationary systems. These methods were used to investigate the properties of arterial stiffness and systemic resistance for a pig's cardiovascular system via ECG and blood pressure (BP). This experiment simulated a sequence of continuous changes of blood pressure arising from steady condition to high blood pressure by clamping the artery and an inverse by relaxing the artery. As a hypothesis, the arterial stiffness and systemic resistance should vary with the blood pressure due to clamping and relaxing the artery. The results show statistically significant correlations between BP, EEMD-based RI, and the phase shift between ECG and BP on cardiac oscillation. The two assessments results demonstrate the merits of the EEMD for signal analysis.
Research Center for Adaptive Data Analysis & Center for Dynamical Biomarkers and Translational Medicine, National Central University, Jhongli 3200, Taiwan.
Jia-Rong
JR
Yeh
Tzu-Yu
TY
Lin
Yun
Y
Chen
Wei-Zen
WZ
Sun
Maysam F
MF
Abbod
Jiann-Shing
JS
Shieh
D000465:Algorithms; D000818:Animals; D062186:Arterial Pressure; D001794:Blood Pressure; D002319:Cardiovascular System; D003198:Computer Simulation; D004562:Electrocardiography / Q000379:methods*; D006801:Humans; D008297:Male; D015233:Models, Statistical; D009010:Monte Carlo Method; D009991:Oscillometry / Q000379:methods; D010865:Pilot Projects; D012815:Signal Processing, Computer-Assisted; D013552:Swine