A tissue engineered @entity340 implanted in a juvenile XXXX model.

@entity340 @entity742 @entity460
BACKGROUND: The tissue-engineered (TE) @entity340 was developed to improve the durability of tissue heart valves. The aim of this study was to evaluate morphological and histological changes in a TE @entity340 consisting of decellularized porcine matrices seeded with viable autologous vascular endothelial cells (AVEC). MATERIAL/METHODS: TE valves were implanted into the right ventricular outflow tract of eight juvenile @entity742 and explanted after 7 days, 3 and 6 months. The valves were evaluated visually, by invasive pressure measurements, X-ray, light microscopy, scanning, and transmission electron microscopy. The @entity460 content of the cusps was determined quantitatively by atomic absorption spectrometry. RESULTS: After valve implantation, all animals showed fast recovery with no complications during the observation period. Invasive pressure measurements presented a mean TE valve pressure gradient of 1.5+/-0.5 mm Hg at 3 and the same at 6 months. Light microscopy showed a monolayer of AVEC on all explanted heart valves, confirmed by scanning electron microscopy and immunohistochemical staining. X-ray examination of explanted TE heart valves showed no cusp calcification, confirmed by atomic absorption spectrometry. CONCLUSIONS: All explanted TE heart valves showed AVEC at the inner surface and ingrowth of fibroblast into the decellularized matrix, increasing during the observation period. The @entity460 contents were very low at explantation in these viable new heart valves.
