本研究的目的是設計出一個理想的人工心瓣。雖然人工心瓣發展已經超過半個世紀，但目前臨床上所使用的機械心瓣還是存在血栓與溶血等缺點，而生物心瓣卻有不耐用的問題。本文利用分析各種三葉片機械心瓣的專利和相關文獻，進而提出全新的改良設計。新設計的葉片與環座是完全以自由曲面所建構而成，外形平順完整而沒有突出的支架，具有圓滑的轉軸，使葉片能夠靈活地轉動。 然後以鈦合金製作實驗原型，提供實驗團隊進行體外流場實驗分析，以驗證新設計的流場性能表現與發展可行性。然後根據新設計的概念，提出美國專利申請，作為後續發展三葉片機械心瓣的基礎。 根據實驗原型的設計經驗，以全面的觀點來探討三葉片心瓣設計所可能遇到的問題與解決策略，歸納成初步的設計準則，提供後續研究人員作進一步的深入分析與討論。 The main objective of the thesis is trying to design the optimal heart valve prosthesis. Since 1952, when the first artificial heart valve was implanted in a human, cardiac surgeons have been looking for a perfect heart valve prosthesis. Currently, there are two major types of valve prostheses used clinically. Patients with mechanical valves require consistent anti-coagulation therapy to prevent complications like thrombosis and hemolysis. Biological valves have much less durability than mechanical valves. This thesis presents the completely redesigned mechanical heart valve from patent analysis. The novel trileaflet mechanical heart valve may have a capability to provide excellent valve durability and hemodynamics. The leaflets and ring are totally created by freeform surface modeling. The streamline shape design provides advantage of fluid dynamic and improves washing of the hinge regions that minimize blood clotting tendencies. Leaflets can rotate freely without much friction, but does not wobble. According to the experience in prototype design, we provide the design critera of the trileafet mechanical heart valve. Furthermore, we have applied for a patent on the new trileaflet heart valve. The design concept was therefore adopted as the basis for the further study and development.
