title: In vitro hydrodynamic evaluation of a biovalve with stent (tubular leaflet type) for transcatheter pulmonary valve implantation.
abstract: We have been developing an autologous heart valve-shaped tissue with a stent (stent-biovalve) for transcatheter pulmonary valve implantation (TPVI) using "in-body tissue architecture" technology. In this study, the hydrodynamic performance of a stent-biovalve with tubular leaflets was evaluated by changing its leaflet height in an in vitro test in order to determine the appropriate stent-biovalve form for the pulmonary valve. A specially designed, self-expandable, stent-mounted, cylindrical acrylic mold was placed in a dorsal subcutaneous pouch of goat, and the implant was extracted 2 months later. Only the cylindrical acrylic mold was removed from the implant, and a tubular hollow structure of membranous connective tissue impregnated with the stent strut was obtained. Half of tubular tissue was completely folded in half inwards, and 3 commissure parts were connected to form 3 leaflets, resulting in the preparation of a stent-biovalve with tubular leaflets (25-mm ID). The stent-biovalve with adjusting leaflet height (13, 14, 15, 17, 20, and 25 mm) was fixed to a specially designed pulsatile mock circulation circuit under pulmonary valve conditions using 37 °C saline. The mean pressure difference and effective orifice area were better than those of the biological valve. The lowest and highest leaflet heights had a high regurgitation rate due to lack of coaptation or prevention of leaflet movement, respectively. The lowest regurgitation (ca. 11%) was observed at a height of 15 mm. The leaflet height was found to significantly affect the hydrodynamics of stent-biovalves, and the existence of an appropriate leaflet height became clear.
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan. sumikura@ri.ncvc.go.jp.
authors.forename: Hirohito
authors.initials: H
authors.lastname: Sumikura
authors.affiliation: Division of Medical Engineering and Materials, National Cerebral and Cardiovascular Center Research Institute, Osaka, Japan.
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Nakayama
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Ohnuma
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Satoru
authors.initials: S
authors.lastname: Kishimoto
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Takewa
authors.affiliation: Department of Artificial Organs, National Cerebral and Cardiovascular Center Research Institute, 5-7-1 Fujishiro-dai, Suita, Osaka, 565-8565, Japan.
authors.forename: Eisuke
authors.initials: E
authors.lastname: Tatsumi
mesh_terms: D000818:Animals; D001705:Bioprosthesis; D006041:Goats; D006350:Heart Valve Prosthesis; D019918:Heart Valve Prosthesis Implantation; D057446:Hydrodynamics; D008422:Materials Testing; D008955:Models, Cardiovascular; D011474:Prosthesis Design; D011664:Pulmonary Valve; D015607:Stents
keywords: Autologous tissue; Biovalve; Hydrodynamic evaluation; Pulmonary valve; Pulsatile circulation circuit