The relationship between different pulse wave velocity and systolic/diastolic pressure

Blood pressure is an important indication of whether the cardiovascular system is in healthy state. In order to continuously measure the non-invasive blood pressure using pulse wave velocity, different pulse wave velocities respective to systolic pressure and diastolic pressure must be studied. In this paper, instead of using ECG together with one pulse wave, two independent pulse waves (one from ear and the other from toe) are acquired using optical sensors. Their time-relationships are studied by pulse contour analysis in order to deeply understand the pulse wave propagation and reflection in arterial system. Then we propose the ways to determine the PWVs relative to systolic/diastolic blood pressure (SBP/DBP) respectively. Real PWVs data relative to DBP/SBP in normal and hypertension conditions are obtained experimentally. By studying these data we can find out the causes of hypertension and some relationship between BP and PWV. We also point out that there is uniform variation law exists between PWV and DBP/ SBP. This implies the possibility of calculating SBP and DBP based on only one mathematical model.