Abstract 8910: In Vitro and i n vivo Performance of a Completely Autologous Aortic Valved Conduit (BIOVALVE Type VII) Prepared by in Body Tissue Architecture Technology Using a Novel Separable Mold

Purpose: In body tissue architecture technology, attempted as novel and practical regeneration medicine by us, can prepare a completely autologous valved conduit (BIOVALVE) consisting of only recipient’s own tissue. In this study, the latest type of BIOVALVE was successfully implanted as an aortic valve in a goat model after in vitro evaluation with a pulsatile circulation circuit. Methods and Results: BIOVALVEs with 3 leaflets in the inner side of the conduit with the sinus of Valsalva were prepared by 2-month embedding of the specially designed separable molds, assembled using 5 plastic parts, in the dorsal subcutaneous spaces of goats. The valve tissue formation in the body was observed non-invasively by wireless capsule endoscope, impregnated into the molds. The obtained BIOVALVE had adequate mechanical properties including highly pressure resistance close to native valves. In vitro evaluation using a pulsatile circulation circuit (LaboHeart NCVC, IWAKI) showed that good valvular function (regurgitation: less than 15%) at mean flow rate of 4.8 L/min, AoP of 129-49 (82.2) mmHg, and beating rate of 70 and high durability (over 1 month). BIOVALVEs (n=3) were implanted in the specially designed apico-aortic bypass of goats to evaluate the possibility as an aortic valve for 1 month. Postoperative echocardiography showed smooth movement of the leaflets with little regurgitation under systemic circulation (2.6 ±1.1 L/min). The luminal surface after implantation was very smooth and covered with thin pseudointima without thrombus formation. Conclusion: Completely autologous BIOVALVE type VII developed satisfied the higher requirements of systemic circulation in vitro and in vivo and has potentiality for clinical application.