TY - JOUR
T1 - In vitro hydrodynamics of four bileaflet valves in mitral position
AU - Feng, Z. G.
AU - Umezu, M.
AU - Fujimoto, T.
AU - Tsukahara, T.
AU - Nurishi, M.
AU - Kawaguchi, D.
N1 - Funding Information:
The authors would like to thank: Century Medical, Inc., Tokyo, Japan, for providing the ATS valves; Japan Lifeline, Inc., Tokyo, for providing the CM valves; Paramedic, Inc., Tokyo, for providing the On-X valves; and Getz Bros. Co. Ltd., Tokyo, for providing the SJM valves. They also express their hearty thanks to Mr. T. Tanaka of Yasuhisa Biomechanics, Inc., Tokyo, for his sound support in developing the pulsatile system. This investigation was supported by the following research funds: the Project Fund (99P13) of Advanced Research Institute for Science and Engineering, Waseda University; the program for promotion of fundamental studies in health science of the organization for drug ADR relief, R&D Promotion and Product Review of Japan (No. 96-12); and Grant-in-aid for scientific research of Japan (No. 09557112, No. 09470288).
PY - 2000
Y1 - 2000
N2 - Hydrodynamics of St. Jude Medical, Carbomedics, Advancing The Standard, and On-X bileaflet valves with an annular diameter of 25 mm were obtained using an in-vitro test system. Steady flow studies demonstrated different pressure drops due to differences in valve design, particularly the geometric orifice diameter and the opening angle. The On-X valve produced the least pressure drop, whereas the Carbomedics valve had the greatest pressure drop. In pulsatile flow experiments, the On-X and St. Jude Medical valves consistently produced the lowest mean positive pressure gradients, while the Carbomedics valve had the highest gradients. In spite of its parallel leaflets design, the On-X valve showed a closing volume as small as that of Carbomedics valve. The results indicate that a larger orifice diameter and greater opening angle can significantly reduce transvalvular pressure loss. This study also demonstrated that attempts to improve the hydrodynamic efficacy of the On-X valve were successful in reducing the pressure gradient as well as maintaining a low closing volume.
AB - Hydrodynamics of St. Jude Medical, Carbomedics, Advancing The Standard, and On-X bileaflet valves with an annular diameter of 25 mm were obtained using an in-vitro test system. Steady flow studies demonstrated different pressure drops due to differences in valve design, particularly the geometric orifice diameter and the opening angle. The On-X valve produced the least pressure drop, whereas the Carbomedics valve had the greatest pressure drop. In pulsatile flow experiments, the On-X and St. Jude Medical valves consistently produced the lowest mean positive pressure gradients, while the Carbomedics valve had the highest gradients. In spite of its parallel leaflets design, the On-X valve showed a closing volume as small as that of Carbomedics valve. The results indicate that a larger orifice diameter and greater opening angle can significantly reduce transvalvular pressure loss. This study also demonstrated that attempts to improve the hydrodynamic efficacy of the On-X valve were successful in reducing the pressure gradient as well as maintaining a low closing volume.
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U2 - 10.1177/021849230000800102
DO - 10.1177/021849230000800102
M3 - Article
AN - SCOPUS:0034054699
SN - 0218-4923
VL - 8
SP - 3
EP - 10
JO - Asian Cardiovascular and Thoracic Annals
JF - Asian Cardiovascular and Thoracic Annals
IS - 1
ER -