Abstract
A new accelerated fatigue tester for artificial heart valves was developed. The test apparatus consists of a water supply duct rotor, two heart valve housings, a centrifugal pump, a reservoir tank and a drive motor. The test were performed at duct cyclic rates of 250-1500 rpm under flow rate into the valve housing of 13.3-27.0l/min. The pressure across the valve and the valve motion operating the tester were monitored to evaluate character-istics of the tester. The water hammer (WH) pressures were observed as the valves closed. The NH differential pressures were at maximum loads to fracture the valves in the tester. In this system the NH dif-ferential pressures increased in proportion to the flow rates. The NH pressures decreased in proportion to the duct cyclic rates. The valve motions were checked by using an image process-ing system at 1000, 1300, 1500 rpm of the duct rotations. The valves opened best at 1000 rpm and operated well at 1300, 1500rpm.
