Objective: Cardiovascular tissue engineering is a novel concept to develop ideal heart valve substitutes. The objective of this study was to use decellularized porcine pulmonary valves, ovine cells and dynamic tissue culture to obtain viable and biomechanically stable constructs, resembling native aortic heart valves.
Methods: Endothelial cells and myofibroblasts were obtained from ovine carotid arteries. Porcine pulmonary valves were decellularized enzymatically, reseeded and cultured using a hydrodynamic bioreactor system over a time period of 9 or 16 days. Controls were grown over an equivalent time period under static conditions. Specimens of each valve were examined biochemically (cell proliferation, DNA, collagen, 4-hydroxyproline, elastin and glycosaminoglycans), histologically (hematoxylin-eosin, Movat-pentachrome and immunostains) and mechanically (radial and circumferential strength).
Results: Histology and biochemical assays demonstrated the removal of almost all cells after decellularization with preservation of the extracellular matrix. Recellularization under pulsatile conditions was significantly improved after 9 and 16 days compared to static conditions. Biochemical and mechanical analysis revealed a continuous increase of cell mass, collagen and elastin contents and strength under pulsatile culture conditions compared to significantly lower values in the static controls.
Conclusion: This study demonstrated the superiority of the hydrodynamic approach of cellular reseeding to replace decellularized porcine heart valves with ovine cells with almost complete preservation of extracellular matrix integrity.
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http://dx.doi.org/10.1016/j.cardiores.2003.09.002 | DOI Listing |
N Z Med J
January 2025
Department of Medicine, HeartOtago, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand; Department of Cardiology, Dunedin Hospital, Southern District Health Board, Dunedin, New Zealand.
Aim: There are limited data on the prevalence of calcific aortic valve disease (CAVD) in Māori and known inequities in outcomes after aortic valve intervention. Our study aimed to investigate the prevalence of CAVD in Māori.
Methods: Data from initial clinically indicated echocardiograms performed between 2010 to 2018 in patients aged ≥18 years were linked to nationally collected outcome data.
Sci Rep
January 2025
Deutsches Herzzentrum der Charité, Department of Congenital and Pediatric Heart Surgery, Augustenburger Platz 1, 13353, Berlin, Germany.
Limited magnetic resonance imaging (MRI) data on autograft dilatation following the Ross procedure in congenital cohorts presents challenges in understanding its evolution and impact on clinical outcomes. This study, spanning from February 2003 to December 2022, included patients under 40 years at the time of the Ross procedure, with MRI follow-ups assessing dimensions at key aortic sites. Among 307 patients, 132 MRIs were analyzed from 76 individuals, revealing that autograft z-scores increase primarily with time post-procedure (Coef.
View Article and Find Full Text PDFOpen Heart
January 2025
Department of Cardiothoracic and Vascular Surgery, and Department of Health, Medicine and Caring Sciences, Linköping University, Linköping, Sweden.
Aims: Exercise testing remains underused in patients with aortic stenosis (AS), partly due to concerns about an exercise-induced drop in systolic blood pressure (SBP). We aimed to study the SBP response to exercise in patients with severe symptomatic AS prior to surgery and 1 year postoperatively.
Methods: Patients scheduled for aortic valve replacement due to severe symptomatic AS were enrolled at a single centre in a prospective observational cohort study.
Open Heart
January 2025
Massachusetts General Hospital, Boston, Massachusetts, USA.
Background: Accurate mortality prediction following transcatheter aortic valve implantation (TAVI) is essential for mitigating risk, shared decision-making and periprocedural planning. Surgical risk models have demonstrated modest discriminative value for patients undergoing TAVI and are typically poorly calibrated, with incremental improvements seen in TAVI-specific models. Machine learning (ML) models offer an alternative risk stratification that may offer improved predictive accuracy.
View Article and Find Full Text PDFJ Investig Med High Impact Case Rep
January 2025
The University of the West Indies, St. Augustine, Trinidad and Tobago.
We describe a 30-year-old Caribbean-Black woman with a clinical presentation suggestive of a transient ischemic attack (TIA) with no conventional cerebrovascular risk factors, albeit with a newly diagnosed quadricuspid aortic valve (QAV) with moderate aortic regurgitation (AR). Although QAV is a recognized congenital cardiac defect, its association with TIA remains elusive. This case highlights the importance of considering potential atypical etiologies, such as QAV, in the evaluation and management of young patients presenting with cerebrovascular events.
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