Preliminary study on the new self-closing mechanical mitral valve

Kiyoshi Naemura, Mitsuo Umezu, T. Dohi

    Research output: Contribution to journalArticle

    8 Citations (Scopus)

    Abstract

    A natural mitral valve starts closing before systole. Conventional mechanical mitral valves start their closing motion after systole. In order to let the mechanical mitral valves start closing before systole, we propose a new self-closing valve by adjusting the center of gravity of the leaflet. As a first step, we adjusted the center of gravity by attaching a block of lead to the leaflet of a CarboMedics bileaflet valve and evaluated it using a pulse duplicator and an x-ray high-speed video camera. Comparative study was conducted under 60 bpm and 4 L/min as the mean flow rate. It was clarified that the self-closing valve started closing before systole, no influence on inflow volume was found, the final closing speed of the self-closing valve just before complete closure was slower than the conventional valve (1.9-0.34 m/s), a design strategy of a self-closing vane (sewing ring diameter 29 mm) was obtained from the experiment that momentum of inertia of the leaflet should be less than 14.9 x 10-9 kg·m2 and the torque caused by gravity should be more than 4.2 x 10-6 N·m, and only one leaflet should be designed as self-closing, and surgeons need to pay attention to the positioning of the two leaflets. In conclusion, the preliminary study showed the ability of starting to close before systole and the design strategy for future prototyping.

    Original languageEnglish
    Pages (from-to)869-875
    Number of pages7
    JournalArtificial Organs
    Volume23
    Issue number9
    DOIs
    Publication statusPublished - 1999

    Fingerprint

    Systole
    Mitral Valve
    Gravitation
    High speed cameras
    Video cameras
    Momentum
    Torque
    Flow rate
    X rays
    X-Rays
    Experiments

    Keywords

    • Center of gravity of the leaflet
    • Design
    • Final closing speed
    • Mechanical mitral valve
    • Motion measurement

    ASJC Scopus subject areas

    • Biophysics

    Cite this

    Preliminary study on the new self-closing mechanical mitral valve. / Naemura, Kiyoshi; Umezu, Mitsuo; Dohi, T.

    In: Artificial Organs, Vol. 23, No. 9, 1999, p. 869-875.

    Research output: Contribution to journalArticle

    Naemura, Kiyoshi ; Umezu, Mitsuo ; Dohi, T. / Preliminary study on the new self-closing mechanical mitral valve. In: Artificial Organs. 1999 ; Vol. 23, No. 9. pp. 869-875.
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