Improvement of fabrication process of vacuum formed valves for ventricular assist device

Mitsuo Umezu, M. Ranawake, T. Nakayama, K. Kobayashi, T. Kido, C. Nojiri, T. Kijima, T. Fujimoto, T. Akutsu

    Research output: Contribution to journalArticle


    In order to provide an inexpensive ventricular assist device (VAD), we developed a 20mL-VAD which was followed by Prof. Kolff's design, but two problems were found; 1) Big amount of regurgitation through inlet bileaflet valve. 2) High resistance of outlet trileaflet valve. Following trials were carried out to settle them; 1) In the manufacturing process of the bileaflet valve, elastic material was used instead of hard plastic plate. Then, regurgitation could be reduced to 1/6. Moreover, total manufacturing process could be dramatically simplified. 2) In the manufacturing process of the trileaflet valve, leaflet thickness was well controlled around 0.2 mm with the aid of a special ring which was located around the valve mold. Then, lower resistance could be achieved by a thin (0.19mm) leaflet valve. Moreover, all valves could be passed the durability testing for 14 days. These data is helpful towards a pre-production stage of the VAD development.

    Original languageEnglish
    Pages (from-to)43-47
    Number of pages5
    JournalJapanese Journal of Artificial Organs
    Issue number1
    Publication statusPublished - 1996



    • Bileaflet valve
    • Regurgitation
    • Trileaflet valve
    • Vacuum forming
    • VAD

    ASJC Scopus subject areas

    • Biophysics

    Cite this

    Umezu, M., Ranawake, M., Nakayama, T., Kobayashi, K., Kido, T., Nojiri, C., Kijima, T., Fujimoto, T., & Akutsu, T. (1996). Improvement of fabrication process of vacuum formed valves for ventricular assist device. Japanese Journal of Artificial Organs, 25(1), 43-47.