Jiuling bileaflet prosthetic heart valve is manufactured in compliance with the national standard of P.R.C. GB12279 90. This mechanical heart valve substitute is constructed entirely of solid low temperature pyrolytic carbon. There is no graphite substrate within the leaflets or orifice. This prosthesis presents with satisfactory histocompatibility and induces little hemocoagulation around it. Objective: This study aimed to assess the hydrodynamic function of the newly China made Jiuling bileaflet heart valve prostheses. Methods: Jiuling valve has been tested in a pulsatile flow simulator in the aortic position. The testing condition was set at the pulsatile frequency of 55, 75, and 100 beats/min and a constant cardiac output of 4 L/min. The mean pressure differences, leakage volumes and closing volumes across each valve, and the effective orifice areas have been analyzed. Results: The Jiuling heart valves prosthesis had the lowest pressure difference at any given tissue annulus diameter. The mean pressure difference of all the Jiuling valves decreases with increasing the tissue annulus diameter or pulse frequency, and is in the range of below 10 mmHg. CarboMedics (CarboMedics, Inc., Austin, Tex.) is similar to that of the 21 mm and 23 mm Jiuling heart valves at the given pulse rate under 4 L/min. C L tilting disc valve (Lanzhou CarboMedics Inc., China) is similar to that of the 23 mm Jiuling heart valve. The effective orifice area of the Jiuling mechanical valve increases with increasing the tissue annulus diameter or pulse frequency. CarboMedics and C L tilting disc valve is similar to that of the 21 mm and 23 mm Jiuling heart valves. The Closing volume of the Jiuling prosthetic cardiac valves increases with increasing the tissue annulus diameter, but decreases with increasing the pulse frequency, and is in the range of below 11% (normalized by stroke volume). CarboMedics is below 16.5% of stroke volume; and C L tilting disc valve is below 7.5%. The leakage volume of the Jiuling prosthetic cardiac valves increases with increasing the tissue annulus diameter, but decreases with increasing the pulse frequency, and are in the range of below 28.9% (normalized by stroke volume). The leakage volume of CarboMedics is higher than that of the same sized 25 mm Jiuling valve, and the C L tilting disc valve is also higher than that of Jiuling valve at 4 L/min. Conclusion: For a given tissue diameter, the Jiuling valve showed significantly better hemodynamic characteristics. The material used in the construction is biocompatible, durable, and thromboresistant. The design permits light weight, low profile, and high ratio of flow area to tissue annulus diameter.
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