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Background: Aortic valve neocuspidization (AVNeo) for trileaflet aortic valve reconstruction using autologous pericardium (Ozaki procedure) offers an alternative treatment modality to overcome drawbacks of conventional prosthetic aortic valve replacement., Methods: Between October 2016 and April 2019, 103 patients underwent surgery. Mean follow-up was 426 ± 270 days. Aortic stenosis was the leading diagnosis in 80 patients (77.7%) and aortic regurgitation in 23 (22.3%), respectively. Mean age was 54.0 ± 16.4 years (range, 13.8-78.5). A bicuspid valve was found in 81 patients (78.6%). Transthoracic echocardiography was performed at discharge and at 6 to 12 months after surgery. During AVNeo surgery valve sizing for an Abbott/St Jude Trifecta bioprosthesis (virtually implanted Trifecta bioprosthesis; St Jude Medical, St Paul, MN) was performed to compare pressure gradients and effective orifice area with published data., Results: Trileaflet aortic valve reconstruction was achieved in all patients. In 38 patients neocommissures were created (36.9%). Mean cross-clamp time was 135 ± 20 minutes. Four patients underwent reoperation; the overall freedom from reoperation was 96.1%. Echocardiographic 6- to 12-months follow-up after surgery was available in 93.8% of patients and did not show any change in hemodynamic parameters compared with discharge. Comparison between AVNeo and virtually implanted Trifecta Bioprosthesis revealed a significantly lower mean pressure gradient (8.5 ± 3.7 mm Hg vs 10.2 ± 2.0 mm Hg, P < .001) and higher mean effective orifice area (2.2 ± 0.7 cm 2 vs 2.1 ± 0.4 cm 2 , P = .037) for AVNeo., Conclusions: AVNeo shows low reoperation rates after surgery within the first 2 years. The hemodynamic performance is excellent, and the effective orifice area and mean pressure gradient remain stable within the first year., (Copyright © 2021 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Tissue engineering of autologous heart valves with the potential to grow and to remodel represents a promising concept. Here we describe the use of cryopreserved umbilical cord blood-derived CD133(+) cells as a single cell source for the tissue engineering of heart valves., Methods: After expansion and differentiation of CD133(+) cells, phenotypes were analyzed by immunohistochemistry and cryopreserved. Heart valve scaffolds fabricated from a biodegradable polymer (n = 8) were seeded with blood-derived myofibroblasts and subsequently coated with blood-derived endothelial cells. Afterward, the heart valve constructs were grown in a pulse duplicator system. Analysis of all heart valves, including histology, immunohistochemistry, electron microscopy, fluorescence imaging, and biochemical and biomechanical examination, was performed., Results: The tissue-engineered heart valves showed endothelialized layered tissue formation including connective tissue between the inside and the outside of the scaffold. The notion of an intact endothelial phenotype was substantiated by fluorescence imaging studies of cellular nitric oxide production and Ca(2+) signaling. Electron microscopy showed that the cells had grown into the pores and formed a confluent tissue layer. Biochemical examination showed extracellular matrix formation (77% +/- 9% collagen of human pulmonary leaflet tissue [HPLT], 85% +/- 61% glycosaminoglycans of HPLT and 67% +/- 17% elastin of HPLT)., Conclusions: Importantly, this study demonstrates in vitro generation of viable human heart valves based on CD133(+) cells derived from umbilical cord blood. These findings constitute a significant step forward in the development of new clinical strategies for the treatment of congenital defects., (2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)