Better Understanding of Blood Rheology by Cardiologists Is Changing the Practice of Care
The progression of cardiovascular disease can be decreased or arrested altogether through monitoring and controlling whole blood viscosity (WBV), alleviating acute symptoms without the need for surgical intervention. As a by-product of surgical therapies such as coronary artery bypass graft, blood loss during these invasive procedures significantly reduces WBV due to reduced hematocrit. However WBV and blood flow measurements provide much more information than available with hematocrit or blood pressure alone, information that is also not available in diagnostic measures of metabolism, lipids, inflammation, EKG or imaging.
In the field of cardiology, measures of blood rheology, such as WBV, blood perfusion rate, shear stress, and thrombotic rate must be utilized more.
- A critical stenosis over 80% significantly reduces distal blood flow due to the large pressure drop across the lesion.
- Blood flow distal to stenoses creates a recirculation region, which is characterized by increased variability in wall shear stresses and vulnerability of atherosclerotic plaque to shear stress induced rupture.
- Increased whole blood viscosity (WBV) increases the residence time of erythrocytes, white cells, platelets, and lipids near the recirculation region, accelerating the process of inflammation. Over time, the recirculation of blood becomes more intense, rending the stenosis to become more severe.