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Updated: Dec 9, 2025
04:32
A Uniform Shear Assay for Human Platelet and Cell Surface Receptors via Cone-plate Viscometry
Published on: June 5, 2019
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Dynamic changes in platelets caused by shear stress in aortic valve stenosis
Hideaki Kanda1, Munekazu Yamakuchi2, Kazuhisa Matsumoto1
1Cardiovascular and Gastroenterological Surgery, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Clinical Hemorheology and Microcirculation
|September 14, 2020
Summary
Shear stress significantly impacts platelet count and function in patients with aortic valve stenosis. Aortic valve replacement surgery alters these effects, with improvements noted in higher pressure gradient groups.
Area of Science:
- Cardiovascular Medicine
- Hematology
- Biomedical Engineering
Background:
- Turbulent blood flow in aortic valve stenosis (AS) alters platelet morphology and coagulation factors.
- Understanding these changes is crucial for managing AS patients.
Purpose of the Study:
- To investigate the effects of shear stress on platelets and coagulation factors in AS patients.
- To analyze how aortic valve replacement (AVR) impacts these parameters.
Main Methods:
- Retrospective analysis of 78 patients undergoing AVR for AS.
- Evaluation of platelet count (PLT), platelet distribution width (PDW), mean platelet volume (MPV), platelet large cell ratio (P-LCR), and plateletcrit (PCT) before and after AVR.
- Comparison between high (HPPG > 100 mmHg) and low (LPPG < 100 mmHg) peak pressure gradient groups.
Main Results:
- PLT count decreased post-AVR but returned to preoperative levels by discharge.
- PDW, MPV, and P-LCR increased post-AVR then decreased below preoperative levels.
- Improvements in PLT count and related indices were more pronounced in the HPPG group.
- Plateletcrit (PCT) increased post-AVR due to reduced shear stress, associated with lower PLT count and higher PDW.
Conclusions:
- Shear stress is a key factor influencing platelet count, PDW, and fibrinogen in AS patients.
- AVR alters platelet dynamics, with significant changes observed in platelet indices.
- The degree of pre-operative pressure gradient influences post-operative platelet recovery.
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