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Journal of the American College of... Apr 2022
Topics: Aortic Valve; Aortic Valve Stenosis; Balloon Valvuloplasty; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Heart Valves; Humans; Prosthesis Design; Transcatheter Aortic Valve Replacement; Treatment Outcome
PubMed: 35393015
DOI: 10.1016/j.jacc.2022.02.029 -
Cardiovascular Engineering and... Jun 2018
Topics: Animals; Biomechanical Phenomena; Bioprosthesis; Cardiovascular Agents; Heart Valve Diseases; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Heart Valves; Hemodynamics; Humans; Mechanotransduction, Cellular; Prosthesis Design; Regeneration; Tissue Engineering
PubMed: 29761407
DOI: 10.1007/s13239-018-0360-3 -
Biomaterials Dec 2019The native human heart valve leaflet contains a layered microstructure comprising a hierarchical arrangement of collagen, elastin, proteoglycans and various cell types.... (Review)
Review
The native human heart valve leaflet contains a layered microstructure comprising a hierarchical arrangement of collagen, elastin, proteoglycans and various cell types. Here, we review the various experimental methods that have been employed to probe this intricate microstructure and which attempt to elucidate the mechanisms that govern the leaflet's mechanical properties. These methods include uniaxial, biaxial, and flexural tests, coupled with microstructural characterization techniques such as small angle X-ray scattering (SAXS), small angle light scattering (SALS), and polarized light microscopy. These experiments have revealed complex elastic and viscoelastic mechanisms that are highly directional and dependent upon loading conditions and biochemistry. Of all engineering materials, polymers and polymer-based composites are best able to mimic the tissue-level mechanical behavior of the native leaflet. This similarity to native tissue permits the fabrication of polymeric valves with physiological flow patterns, reducing the risk of thrombosis compared to mechanical valves and in some cases surpassing the in vivo durability of bioprosthetic valves. Earlier work on polymeric valves simply assumed the mechanical properties of the polymer material to be linear elastic, while more recent studies have considered the full hyperelastic stress-strain response. These material models have been incorporated into computational models for the optimization of valve geometry, with the goal of minimizing internal stresses and improving durability. The latter portion of this review recounts these developments in polymeric heart valves, with a focus on mechanical testing of polymers, valve geometry, and manufacturing methods.
Topics: Animals; Biomechanical Phenomena; Heart Valve Prosthesis; Heart Valves; Humans; Polymers; Prosthesis Design; Stress, Mechanical
PubMed: 31569017
DOI: 10.1016/j.biomaterials.2019.119493 -
Philosophical Transactions of the Royal... Aug 2007Each heart valve is composed of different structures of which each one has its own histological profile. Although the aortic and the pulmonary valves as well as the... (Review)
Review
Each heart valve is composed of different structures of which each one has its own histological profile. Although the aortic and the pulmonary valves as well as the mitral and the tricuspid valves show similarities in their architecture, they are individually designed to ensure optimal function with regard to their role in the cardiac cycle. In this article, we systematically describe the structural elements of the four heart valves by different anatomical, light- and electron-microscopic techniques that have been presented. Without the demand of completeness, we describe main structural features that are in our opinion of importance in understanding heart valve performance. These features will also have important implications in the treatment of heart valve disease. They will increase the knowledge in the design of valve substitutes or partial substitutes and may participate to improve reconstructive techniques. In addition, understanding heart valve macro- and microstructure may also be of benefit in heart valve engineering techniques.
Topics: Biomechanical Phenomena; Blood Circulation; Heart Valves; Humans
PubMed: 17581807
DOI: 10.1098/rstb.2007.2125 -
International Journal of Surgery... Oct 2021Valve disease carries a huge burden globally and the number of heart valve procedures are projected to increase from the current 300 000 to 800 000 annually by 2050.... (Review)
Review
Valve disease carries a huge burden globally and the number of heart valve procedures are projected to increase from the current 300 000 to 800 000 annually by 2050. Since its genesis 50 years ago, pericardial heart valve has moved leaps and bounds to ever more ingenious designs and manufacturing methods with parallel developments in cardiology and cardiovascular surgical treatments. This feat has only been possible through close collaboration of many scientific disciplines in the fields of engineering, material sciences, basic tissue biology, medicine and surgery. As the pace of change continues to accelerate, we ask the readers to go back with us in time to understand developments in design and function of pericardial heart valves. This descriptive review seeks to focus on the qualities of pericardial heart valves, the advantages, successes and failures encapsulating the evolution of surgically implanted pericardial heart valves over the past five decades. We present the data on comparison of the pericardial heart valves to porcine valves, discuss structural valve deterioration and the future of heart valve treatments.
Topics: Animals; Aortic Valve; Bioprosthesis; Forecasting; Heart Valve Diseases; Heart Valve Prosthesis; Heart Valve Prosthesis Implantation; Pericardium; Prosthesis Design; Swine
PubMed: 34543742
DOI: 10.1016/j.ijsu.2021.106121 -
Cardiovascular Engineering and... Feb 2021Heart valves function in one of the most mechanically demanding environments in the body to ensure unidirectional blood flow. The resident valve interstitial cells... (Review)
Review
Heart valves function in one of the most mechanically demanding environments in the body to ensure unidirectional blood flow. The resident valve interstitial cells respond to this mechanical environment and maintain the structure and integrity of the heart valve tissues to preserve homeostasis. While the mechanics of organ-tissue-cell heart valve function has progressed, the intracellular signaling network downstream of mechanical stimuli has not been fully elucidated. This has hindered efforts to both understand heart valve mechanobiology and rationally identify drug targets for treating valve disease. In the present work, we review the current literature on VIC mechanobiology and then propose mechanistic mathematical modeling of the mechanically-stimulated VIC signaling response to comprehend the coupling between VIC mechanobiology and valve mechanics.
Topics: Biophysics; Heart Valves; Signal Transduction
PubMed: 33527256
DOI: 10.1007/s13239-020-00509-4 -
Nature Reviews. Cardiology Dec 2014During every heartbeat, cardiac valves open and close coordinately to control the unidirectional flow of blood. In this dynamically challenging environment, resident... (Review)
Review
During every heartbeat, cardiac valves open and close coordinately to control the unidirectional flow of blood. In this dynamically challenging environment, resident valve cells actively maintain homeostasis, but the signalling between cells and their microenvironment is complex. When homeostasis is disrupted and the valve opening obstructed, haemodynamic profiles can be altered and lead to impaired cardiac function. Currently, late stages of cardiac valve diseases are treated surgically, because no drug therapies exist to reverse or halt disease progression. Consequently, investigators have sought to understand the molecular and cellular mechanisms of valvular diseases using in vitro cell culture systems and biomaterial scaffolds that can mimic the extracellular microenvironment. In this Review, we describe how signals in the extracellular matrix regulate valve cell function. We propose that the cellular context is a critical factor when studying the molecular basis of valvular diseases in vitro, and one should consider how the surrounding matrix might influence cell signalling and functional outcomes in the valve. Investigators need to build a systems-level understanding of the complex signalling network involved in valve regulation, to facilitate drug target identification and promote in situ or ex vivo heart valve regeneration.
Topics: Cellular Microenvironment; Extracellular Matrix; Heart Valve Diseases; Heart Valves; Homeostasis; Humans; In Vitro Techniques; Signal Transduction
PubMed: 25311230
DOI: 10.1038/nrcardio.2014.162 -
Archives of Disease in Childhood Dec 1985
Topics: Bioprosthesis; Child; Child, Preschool; Heart Valve Diseases; Heart Valve Prosthesis; Heart Valves; Humans; Infant
PubMed: 4091576
DOI: 10.1136/adc.60.12.1111 -
Circulation Research Aug 2009In recent years, significant advances have been made in the definition of regulatory pathways that control normal and abnormal cardiac valve development. Here, we review... (Review)
Review
In recent years, significant advances have been made in the definition of regulatory pathways that control normal and abnormal cardiac valve development. Here, we review the cellular and molecular mechanisms underlying the early development of valve progenitors and establishment of normal valve structure and function. Regulatory hierarchies consisting of a variety of signaling pathways, transcription factors, and downstream structural genes are conserved during vertebrate valvulogenesis. Complex intersecting regulatory pathways are required for endocardial cushion formation, valve progenitor cell proliferation, valve cell lineage development, and establishment of extracellular matrix compartments in the stratified valve leaflets. There is increasing evidence that the regulatory mechanisms governing normal valve development also contribute to human valve pathology. In addition, congenital valve malformations are predominant among diseased valves replaced late in life. The understanding of valve developmental mechanisms has important implications in the diagnosis and management of congenital and adult valve disease.
Topics: Animals; Cell Differentiation; Cell Lineage; Cell Proliferation; Endocardial Cushions; Extracellular Matrix; Gene Expression Regulation, Developmental; Heart Defects, Congenital; Heart Valve Diseases; Heart Valves; Humans; Signal Transduction
PubMed: 19713546
DOI: 10.1161/CIRCRESAHA.109.201566 -
Circulation Research Apr 2020
Topics: Animals; Cell Differentiation; Heart Valves; Organogenesis; Transcription Factors; Zebrafish
PubMed: 32271684
DOI: 10.1161/CIRCRESAHA.120.316846