Photoplethysmographic measurements of arterial and aortic pulse waveform characteristics
Keywords:arterial elasticity measurement, photoplethysmography (PPG), pulse wave decomposition, logarithmic transform
The photoplethysmographic (PPG) signal is a complex signal, composed of the peripheral pulse synchronized to each heartbeat (the fluctuating component), and modulated by a slow component that varies due to respiration, vasomotor activity and vasoconstrictor waves, ECG and pulse waves from healthy subjects. Decomposition of the PPG pulse waves produces five components: percussion, tidal, dicrotic, repercussion, and retidal waves. Pulse wave decomposition parameters PPG are compared to detect variables for information on person’s arterial elasticity. Nowadays, promising cardiovascular parameters registration method is PPG, which is relatively simple to be applied in eHealth, clinical applications, homecare, drives’ sleepiness, or even endothelial dysfunction. Results show that elasticity information in the form of pulse wave decomposition from PPG waves is easily obtainable and shows clear shortening between percussion wave and tidal wave peak time in PPG waveforms as a function of age. Decomposition analysis is valuable in assessment of the arterial elasticity. In addition, PPG measurement is absolutely non‐invasive and safe. In PPG measurement, the sensors are on the opposite sides of the fingertip to obtain accurate waveforms. A further challenge is the calibration of the PPG measurement systems in order to achieve comparative diagnostic relations, because PPG waveforms in different regions of the body and in different subjects do not allow us to find a universal calibration function for reliable estimations of the clinical data.