Regurgitation of a mini azial pump with closed impeller used as a valvo-pump
The back-flow of an aortic valvo-pump will reduce the pumping flow rate but can wash out the gap between the rotor and the stator, and thus can improve the antithrombogenicity of the device. To investigate the regurgitation of a 23mm OD aortic valvo-pump, its closed impeller was replaced by a cylinder and hereby the valvo-pump had lost its pumping function. The pressure head crossing the aortic valvo-pump was maintained by a pulsatile centrifugal pump, beating rhythmically from 0 to 120mmHg. The back flow from outlet to inlet of valvo-pump via the above-mentioned gap was measured. Results demonstrated that this gap and the pressure head had remarkable effect on back-flow; a larger gap and/or a larger pressure head would lead to a larger back-flow. By 0,20mm gap and 100mmHg pressure head, the valvo-pump had ca. 0,8 l/min back-flow. Instantaneous measurement indicated that the back-flow had a pulsatile form with high rate during diastole while low rate during systole of the natural heart imitated by pulsatile centrifugal pump. The pump rotated at 12500rpm, 15000rpm and 17500rpm respectively, but it was found the rotating speed had no affection on back-flow. This investigation provides a basis for pump design seeking for both increase of the flow rate and improvement of the compatibility; the former is particularly important for a mini pump and the latter is extremely difficult for closed impeller.
aortic valvo-pump regurgitation measurement different air-gap and pressure head Anti-thrombogenicity
Qian KX Ji Ying
Institute of Biomedical Engineering Jiangsu University Zhenjiang, China, 212013 School of Finance and Economic Jiangsu University Zhenjiang, China, 212013
国际会议
上海
英文
1329-1331
2008-05-16（万方平台首次上网日期，不代表论文的发表时间）