抄録
We have studied the relationship between surface roughness and hemolysis to develop a blood compatible artificial heart. Hemolysis tests with bovine blood were performed by using rotating shear stressors, which have different surface roughness on inner cylinders. The roughness of the standard stressor was 0.3μmRa. The roughness on the 10% area of the inner cylinder circumferential area was changed to 0.8,6.2,and 9.2μmRa in the tested stressors. The stressors were rotated for 30 minutes with a rotating speed to 1000 and 400rpm. Flow visualization studies were also performed to investigate the flow condition in the blood gap of the stressor. Laminar flow was observed in the stressor gap with a rotating speed of 1000rpm and turbulent flow was obtained with a rotating speed of 4000rpm. It was revealed that threshold roughness for hemolysis is between 0.3 and 0.8μmRa roughness in the laminar flow condition, and between 0.8 and 6.2μmRa roughness in the turbulent flow condition. It is recommended that the surface roughness of artificial hearts should be less than 0.3μmRa.
