Shear stress investigation across mechanical heart valve.

School of Mechanical and Automation Engineering, Shanghai Institute of Technology, Shanghai, China.
ASAIO journal (American Society for Artificial Internal Organs: 1992) (Impact Factor: 1.39). 01/2007; 53(5):530-6. DOI: 10.1097/MAT.0b013e318157c093
Source: PubMed

ABSTRACT The particle image velocimetry technique was used to study the shear field across a transparent mechanical heart valve model in one cardiac cycle. Shear stress was continuously increased until peak systole and high turbulent stress was observed at the orifice of the central channel and also around the occluder trailing tips. The peak Reynolds shear stress was up to 500 N/m at peak systole, which was higher than the normal threshold for hemolysis.

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