Do only the vascular atherosclerosis-related risk factors affect the value of pulsed wave velocity? Blood density or viscosity effect on pulsed wave velocity

Abstract

Aortic stiffness expressed as aortic pulse wave velocity (PWV) is a strong predictor of future CV events and all-cause mortality. The predictive ability of arterial stiffness is higher in subjects with a higher baseline CV risk. There is a general agreement that arterial stiffness has an important predictive role. Most studies have focused on classic risk factors confined to vascular status. However, there might be some relation between blood flowand vascularwall. So, our hypothesis is that hemorheologic parameters such as blood viscosity, shear rate, and shear stress might affect to PWV as a fluid dynamic mechanism. We have measured and analyzed the PWV, hemorheologic parameters, and other clinical parameters in patients scheduled for coronary angiography. This study showed that an association between known clinical risk factors, such as, age, hypertension, dyslipidemia, smoking, and renal insufficiency were positively associated with the value of PWV. However, the hemorheological abnormalities were diversely associated with PWV. While initial hypothesis was that the viscosity might significantly affect the value of PWV with positive correlation, the results shows that the viscosity and the hematocrit were negatively, and critical shear ratewas positively correlated with PWV. These results suggest that PWV might be affected by shear rate than the viscosity itself. Additionally, flow increasing factors such as shear rate, central blood pressure, and pulse pressuremight affect PWV, hemodynamically. This resultmight provide the useful information on the characteristics of RBC aggregation and hemorheological effect on PWV.