METHOD AND DEVICE FOR MEASURING THE PULSE WAVE PROPAGATION VELOCITY WHEN MEASURING BLOOD PRESSURE BY OSCILLOMETRIC METHOD Russian patent published in 2021 - IPC A61B5/22 A61B5/285 A61B5/295 

FIELD: medicine.

SUBSTANCE: group of inventions relates to medicine, namely, to a method and device for simultaneous non-invasive measurement of blood pressure (BP) and pulse wave propagation velocity (WPV) in blood vessels. In this case, the PV of air pressure in the compression cuff (5) of the tonometer (4) on the patient's shoulder is recorded during pumping or releasing pressure in the cuff at the interval between systolic and diastolic pressures. At the same time, at the same interval between the systolic and diastolic pressures, the PV of pressure in the area of the big toe is recorded by photoplethysmography (PPG). The waveform signals from the tonometer cuff and the PPG signals are processed. The time delay of the propagation of the PV pressure ∆T_i between the shoulder and the toe is determined as the time difference between the i-th local maxima of the second derivatives of the PPG signals and the waveform, respectively. The integral value of the WPV using the formula is calculated: PWVe = (D₂-D₁)/∆T_av, where D₁ is the distance between the heart and the middle of the shoulder, D₂ is the distance between the heart and the area of the big toe, ∆T_av the average time delays ∆T_i for all the pressure pulses of the PV in the waveform and PPG signals. The device contains an automatic blood pressure monitor (4) for measuring blood pressure with a cuff (5) and an optical PPG sensor (6). The electronic unit (8) of the tonometer contains a digital filtration unit (83) with an adjustable group delay of τ1 to obtain from the pressure signal an oscillogram of its pulsating part and a constant component of the pressure in the cuff. The PPG sensor contains a digital filtering unit (63) with an adjustable group delay of τ2 to receive the PPG signal.

EFFECT: simultaneous measurement of blood pressure and WPV by the "two-point" method allows for measurements in one stage. Measurement errors and errors associated with different signal delays in different electronic components of the device are minimized. Fast, accurate and reliable determination of the integral WPV in vessels of different hierarchies along the entire body is achieved, with the possibility of making measurements at home.

9 cl, 6 dwg