Physical Investigation of Hemo-Rheological Characteristics for Cardiac Surgery Patients
Yi-Fan Wu1,2*, Po-Shun Hsu3, Chien-Sung Tsai3, Yeng-Long Chen1,2
1Institute of Physics, Academia Sinica, Taipei, Taiwan
2Department of Chemical Engineering, National Tsing-Hua University, Hsinchu, Taiwan
3Division of Cardiovascular Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
* Presenter:Yi-Fan Wu
We have employed a high sensitivity physical measurements of blood viscosity and elasticity to examine the differences between healthy people and patients who have underwent cardiovascular surgery. Cardiovascular diseases (CVD) and heart-related complications mortality have remained the main cause of death worldwide at this time[1]. However, current indicators for rehabilitation are both expensive and time-consuming.
Coronary Artery Bypass Graft (CABG) and Mitral Valve Replacement (MVR) surgeries are widely accepted treatments for advanced atherosclerosis and coronary artery disease. There are high risk related to post-operative complications such as cerebral ischemia, systemic inflammation, deep vein thrombosis, and endothelial injury, etc. However, current indicators for rehabilitation are both expensive and time-consuming.
Hemorheology is an established tool for monitoring the blood perfusion efficacy and health care for surgical patients. We recruited twenty-seven CVD patients (N=27) who required a cardiopulmonary bypass (CPB). Each assessment involved a baseline recording before surgical procedure(M0), one day(M1), one week(M2) and one year(M3) following surgery. The viscosity and elastic modulus were measured by using a Physica Rheometer MCR 501(Anton-Paar, Graz, Austria)[2]. Moreover, the questionnaire recorded the quality of the patients habits in their life (smoking habit, diastolic blood pressure, and low-density lipoprotein cholesterol).
We found an increase in whole blood viscosity (WBV) correlated with an elevated C-reactive protein and plasma fibrinogen levels[3]. Blood viscosity was found to be higher for the patients than for the healthy control group. WBV were also elevated in the post-surgical group(M1, M2) than the pre-surgery group (M0), possibly due to acute-phase response for surgery intervention. However, WBV returned to baseline in one year after surgery (M3)

References
[1] GA Roth. et al, N Engl J Med, 372, 1333 (2015)
[2] G Tomaiuolo. et al, Rheol Acta, 55 ,485 (2015).
[3] A Matrai. et al, Clin Hemorheol, 7, 2 (1987).


Keywords: Hemorheology, RBC aggregation, Cardiopulmonary Bypass