Special Issue "Mitral Valve Development and Disease"

A special issue of Journal of Cardiovascular Development and Disease (ISSN 2308-3425).

Deadline for manuscript submissions: closed (31 July 2021).

Special Issue Editors

Dr. Nina Ajmone Marsan
E-Mail Website
Guest Editor
Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherland
Interests: mitral valve prolapse; mitral regurgitation; aortic stenosis; cardiovascular imaging
Special Issues and Collections in MDPI journals
Prof. Dr. Russell Norris
E-Mail Website
Guest Editor
Department of Regenerative Medicine and Cell Biology, Cardiovascular Developmental Biology Center, Children's Research Institute, Medical University of South Carolina, 173 Ashley Avenue, Charleston, SC 29425, USA
Interests: cardiac development; valve development; cardiovascular genetics; valve diseases; mitral valve prolapse; calcific aortic stenosis; ischemic MR; HOCM; myxomatous valves; fibroblast- myocyte interactions; fibrosis; primary cilia; cytoskeleton; membrane receptors; transcription factors
Special Issues and Collections in MDPI journals

Special Issue Information

Mitral valve disease, the focus of this Special Issue, is one of the most common forms of cardiac valve disease and affects ~2%–3% of the human population. As such, mitral valve defects carry a significant burden of morbidity and mortality and can lead to secondary complications such as arrhythmias, heart failure, and sudden cardiac death. Mitral valve surgery is currently the only therapeutic option for these patients, and is the fastest-growing cardiovascular intervention in the Western world. There are no effective nonsurgical treatments for this group of diseases, and therapeutic efforts have been hindered by an incomplete understanding of their fundamental causes. In recent years, our understanding of the genetic and molecular basis of heart valve diseases has significantly improved. New genetic discoveries have informed true causes of mitral valve disease in the human population. For the most part, cell lineages that contribute to the development of the mitral valve leaflets have been uncovered. However, the way in which these different cell lineages integrate to establish stratified valve tissues is less well understood. More importantly, research on how cellular, molecular, genetic, and epigenetic interactions interface with biomechanical cues to drive normal valve development remains in its infancy. Uncovering how defects in these various intrinsic and extrinsic factors can lead to valvular heart diseases is critical in understanding the pathophysiology of disease. Part and parcel with understanding the etiology of mitral valve disease is an appreciation of whether this understanding can impact clinical management and eventually lead to the development of new medical treatments. New research has suggested that a prolapsing mitral valve can have profound effects on extra-valvular cardiac tissues such as the annulus and left ventricular wall. Establishing mechanisms underlying secondary defects related to mitral valve disease may help inform new clinical management for this disease, with the opportunity of modifying current surgical and imaging guidelines. Similarly, how valve adaptations occur either in the context of new surgical approaches or in other cardiac conditions such as hypertrophic obstructive cardiomyopathies, endocarditis, and rheumatic and ischemic mitral regurgitation will fit logically within the framework of this Special Issue. A goal of this Issue is to stimulate new investigations into primary and secondary mitral valve defects and their relationship to pathological and clinical implications. We invite you to consider contributing a research paper or review article on any aspect related to the topic of this Special Issue. This may be also an opportunity for surgeons, cardiologists, cardiac imagers, clinical fellows, and doctoral and post-doctoral trainees to contribute to a review article and showcase their area of expertise.

Dr. Nina Ajmone Marsan
Dr. Russell Norris
Guest Editors

Manuscript Submission Information

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Keywords

  • Mitral valve disease 
  • Mitral valve development 
  • Myxomatous valves 
  • Primary mitral regurgitation 
  • Secondary mitral regurgitation 
  • Mitral valve stenosis

Published Papers (14 papers)

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Research

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Article
Head to Head Comparison between Different 3-Dimensional Echocardiographic Rendering Tools in the Imaging of Percutaneous Edge-to-Edge Mitral Valve Repair
J. Cardiovasc. Dev. Dis. 2021, 8(7), 73; https://doi.org/10.3390/jcdd8070073 - 24 Jun 2021
Viewed by 516
Abstract
MitraClip (MC) is the most common percutaneous treatment for severe mitral regurgitation (MR). An accurate two-dimensional and three-dimensional echocardiographic (3DTEE) imaging is mandatory for the optimal procedural result. Recently transillumination 3DTEE rendering (3DTr) has been introduced integrating a virtual light source into the [...] Read more.
MitraClip (MC) is the most common percutaneous treatment for severe mitral regurgitation (MR). An accurate two-dimensional and three-dimensional echocardiographic (3DTEE) imaging is mandatory for the optimal procedural result. Recently transillumination 3DTEE rendering (3DTr) has been introduced integrating a virtual light source into the dataset and with the addition of glass effect (3DGl) allows to adjust tissue transparency improving depth perception and anatomical structure delineation in comparison with the standard 3DTEE (3DSt). The aim of this retrospective study in 30 patients undergoing MC, was to compare 3DSt, 3DTr, and 3DGl in mitral valve (MV) evaluation and procedural result assessment. 3DTEE acquisitions obtained before and after MC were processed with 3DSt, 3DTr, and 3DGl rendering. Each reconstruction was scored for quality and for ability to recognize MV anatomy, MR origin, clip position, dimension and grasping. Imaging quality was judged good or optimal in 52%, 76%, and 96% in 3DSt, 3DTr, and 3DGl reconstructions respectively. In 26/30 patients a diagnostic incremental value was found with 3DTr vs. 3DSt and in 15/26 with 3DGl vs. 3DTr and 3DSt. Only 3DGl with perpendicular cropping of the clip allowed to visualize and measure the grasped portion of each mitral leaflets. 3DTEE imaging during MC may be improved by 3DTr and 3DGl providing a better evaluation of MV, of leaflet grasping and of residual MR jets after MC. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Article
PDGFRα: Expression and Function during Mitral Valve Morphogenesis
J. Cardiovasc. Dev. Dis. 2021, 8(3), 28; https://doi.org/10.3390/jcdd8030028 - 13 Mar 2021
Viewed by 918
Abstract
Mitral valve prolapse (MVP) is a common form of valve disease and can lead to serious secondary complications. The recent identification of MVP causal mutations in primary cilia-related genes has prompted the investigation of cilia-mediated mechanisms of disease inception. Here, we investigate the [...] Read more.
Mitral valve prolapse (MVP) is a common form of valve disease and can lead to serious secondary complications. The recent identification of MVP causal mutations in primary cilia-related genes has prompted the investigation of cilia-mediated mechanisms of disease inception. Here, we investigate the role of platelet-derived growth factor receptor-alpha (PDGFRα), a receptor known to be present on the primary cilium, during valve development using genetically modified mice, biochemical assays, and high-resolution microscopy. While PDGFRα is expressed throughout the ciliated valve interstitium early in development, its expression becomes restricted on the valve endocardium by birth and through adulthood. Conditional ablation of Pdgfra with Nfatc1-enhancer Cre led to significantly enlarged and hypercellular anterior leaflets with disrupted endothelial adhesions, activated ERK1/2, and a dysregulated extracellular matrix. In vitro culture experiments confirmed a role in suppressing ERK1/2 activation while promoting AKT phosphorylation. These data suggest that PDGFRα functions to suppress mesenchymal transformation and disease phenotypes by stabilizing the valve endocardium through an AKT/ERK pathway. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Article
Myocardial TGFβ2 Is Required for Atrioventricular Cushion Remodeling and Myocardial Development
J. Cardiovasc. Dev. Dis. 2021, 8(3), 26; https://doi.org/10.3390/jcdd8030026 - 02 Mar 2021
Viewed by 833
Abstract
Among the three transforming growth factor beta (TGFβ) ligands, TGFβ2 is essential for heart development and is produced by multiple cell types, including myocardium. Heterozygous mutations in TGFB2 in patients of connective tissue disorders result in congenital heart defects and adult valve malformations, [...] Read more.
Among the three transforming growth factor beta (TGFβ) ligands, TGFβ2 is essential for heart development and is produced by multiple cell types, including myocardium. Heterozygous mutations in TGFB2 in patients of connective tissue disorders result in congenital heart defects and adult valve malformations, including mitral valve prolapse (MVP) with or without regurgitation. Tgfb2 germline knockout fetuses exhibit multiple cardiac defects but the role of myocardial-TGFβ2 in heart development is yet to be elucidated. Here, myocardial Tgfb2 conditional knockout (CKO) embryos were generated by crossing Tgfb2flox mice with Tgfb2+/−; cTntCre mice. Tgfb2flox/− embryos were normal, viable. Cell fate mapping was done using dual-fluorescent mT/mG+/− mice. Cre-mediated Tgfb2 deletion was assessed by genomic PCR. RNAscope in situ hybridization was used to detect the loss of myocardial Tgfb2 expression. Histological, morphometric, immunohistochemical, and in situ hybridization analyses of CKOs and littermate controls at different stages of heart development (E12.5–E18.5) were used to determine the role of myocardium-derived TGFβ2 in atrioventricular (AV) cushion remodeling and myocardial development. CKOs exhibit a thin ventricular myocardium, AV cushion remodeling defects and developed incomplete AV septation defects. The loss of myocardial Tgfb2 resulted in impaired cushion maturation and dysregulated cell death. Phosphorylated SMAD2, a surrogate for TGFβ signaling, was “paradoxically” increased in both AV cushion mesenchyme and ventricular myocardium in the CKOs. Our results indicate that TGFβ2 produced by cardiomyocytes acting as cells autonomously on myocardium and via paracrine signaling on AV cushions are required for heart development. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Article
Assessment of D-Shaped Annulus of Mitral Valve in Patients with Severe MR Using Semi-Automated 4-Dimensional Analysis: Implications for Transcatheter Interventions
J. Cardiovasc. Dev. Dis. 2020, 7(4), 48; https://doi.org/10.3390/jcdd7040048 - 01 Nov 2020
Cited by 1 | Viewed by 911
Abstract
The development of transcatheter mitral valve replacement therapies requires accurate post-processing analysis tools to provide D-shaped mitral annulus dimensions from 3-dimensional (3D) data. The agreement between two semi-automated, software packages to process 3D transesophageal echocardiography (TEE) data for the measurement of the mitral [...] Read more.
The development of transcatheter mitral valve replacement therapies requires accurate post-processing analysis tools to provide D-shaped mitral annulus dimensions from 3-dimensional (3D) data. The agreement between two semi-automated, software packages to process 3D transesophageal echocardiography (TEE) data for the measurement of the mitral valve annulus dimensions was evaluated. 3DTEE data of patients with moderate–severe mitral regurgitation (MR) were postprocessed with semi-automated, vendor-independent (VI) software and vendor-specific (VS) software. Both post-processing software provided key measurements for the selection of transcatheter valve prosthesis size: annulus area, annulus circumference and the septal-to-lateral distance of the annulus. The intertrigonal distance was provided only by the VS software. The inter- and intra-observer agreements were assessed with Bland–Altman analysis. Of 105 patients (63.8 ± 11 years, 66% male) with MR, 28 had secondary MR, 45 fibroelastic deficiency, and 32 Barlow’s disease. Using VS software, the dimensions for the overall population were 16.1 ± 4.6 cm2 for annulus area, for circumference 14.4 ± 1.9 cm, intertrigonal distance 3.4 ± 0.5 cm and septal-to-lateral distance 3.8 ± 0.6 cm. Similar dimensions were obtained using VI software: 15.7 ± 4.6 cm2 for annulus area, 14.5 ± 2.0 cm for circumference, and 4.1 ± 0.6 cm for septal-to-lateral distance. The inter- and intra-observer agreement for both software programs was excellent. In conclusion, current post-processing software programs for 3DTEE data of the mitral valve annulus provide good reproducibility of key measurements to select the transcatheter prosthesis size. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Article
Predictive Value of Pre-Operative 2D and 3D Transthoracic Echocardiography in Patients Undergoing Mitral Valve Repair: Long Term Follow Up of Mitral Valve Regurgitation Recurrence and Heart Chamber Remodeling
J. Cardiovasc. Dev. Dis. 2020, 7(4), 46; https://doi.org/10.3390/jcdd7040046 - 20 Oct 2020
Cited by 2 | Viewed by 752
Abstract
The “ideal” management of asymptomatic severe mitral regurgitation (MR) in valve prolapse (MVP) is still debated. The aims of this study were to identify pre-operatory parameters predictive of residual MR and of early and long-term favorable remodeling after MVP repair. We included 295 [...] Read more.
The “ideal” management of asymptomatic severe mitral regurgitation (MR) in valve prolapse (MVP) is still debated. The aims of this study were to identify pre-operatory parameters predictive of residual MR and of early and long-term favorable remodeling after MVP repair. We included 295 patients who underwent MV repair for MVP with pre-operatory two- and three-dimensional transthoracic echocardiography (2DTTE and 3DTTE) and 6-months (6M) and 3-years (3Y) follow-up 2DTTE. MVP was classified by 3DTTE as simple or complex and surgical procedures as simple or complex. Pre-operative echo parameters were compared to post-operative values at 6M and 3Y. Patients were divided into Group 1 (6M-MR < 2) and Group 2 (6M-MR ≥ 2), and predictors of MR ≥ 2 were investigated. MVP was simple in 178/295 pts, and 94% underwent simple procedures, while in only 42/117 (36%) of complex MVP a simple procedure was performed. A significant relation among prolapse anatomy, surgical procedures and residual MR was found. Post-operative MR ≥ 2 was present in 9.8%: complex MVP undergoing complex procedures had twice the percentage of MR ≥ 2 vs. simple MVP and simple procedures. MVP complexity resulted independent predictor of 6M-MR ≥ 2. Favorable cardiac remodeling, initially found in all cases, was maintained only in MR < 2 at 3Y. Pre-operative 3DTTE MVP morphology identifies pts undergoing simple or complex procedures predicting MR recurrence and favorable cardiac remodeling. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Article
Smooth Muscle α-Actin Expression in Mitral Valve Interstitial Cells is Important for Mediating Extracellular Matrix Remodeling
J. Cardiovasc. Dev. Dis. 2020, 7(3), 32; https://doi.org/10.3390/jcdd7030032 - 19 Aug 2020
Cited by 2 | Viewed by 1111
Abstract
Background: Mitral valve prolapse (MVP) affects 3–6% of the total population including those with connective tissue disorders. Treatment is limited, and patients commonly require surgery which can be impermanent and insuperable. Abnormal prolapse of mitral valve leaflets into the left atria is caused [...] Read more.
Background: Mitral valve prolapse (MVP) affects 3–6% of the total population including those with connective tissue disorders. Treatment is limited, and patients commonly require surgery which can be impermanent and insuperable. Abnormal prolapse of mitral valve leaflets into the left atria is caused by disturbances to the composition and organization of the extracellular matrix (ECM), that weaken biomechanics. This process, known as myxomatous degeneration is characterized by an abnormal accumulation of proteoglycans, in addition to collagen fiber disruption and elastic fiber fragmentation. The underlying mechanisms that promote myxomatous degeneration to the point of biomechanical failure are unknown, but previous histological studies of end-stage diseased tissue have reported abnormal α-smooth muscle actin (SMA) in a subset of heart valve interstitial cells (VICs); however, the contribution of these abnormal cells to MVP pathogenesis has not been extensively examined. Methods: In vivo and in vitro approaches were used. Mice harboring a Fbn1C1039G mutation mimic human Marfan Syndrome and develop MVP. Using these mice, temporal and spatial changes in SMA expression relative to myxomatous degeneration were examined using histological techniques. In parallel in vitro experiments, SMA expression was downregulated in primary porcine mitral VICs directly using siRNA, and indirectly using the actin depolymerizing agent Latrunculin A. In addition, the regulation of SMA in VICs by mechanical stiffness was explored relative to ECM remodeling. Results: We show, in mitral valves from Fbn1C1039G/+ mice, that abnormal increases in SMA expression in VICs are evident during early postnatal stages of disease, prior to significant myxomatous degeneration as indicated at later stages by increased proteoglycans and collagen type I (Col1a1). Furthermore, abnormal SMA expression continues to increase during the course of pathogenesis and is localized to the mid belly region of the mitral valve leaflets from 10 weeks. Using an in vitro approach, we demonstrate that reduced SMA function by direct siRNA or indirect Latrunculin A treatment attenuates proteoglycan and Col1a1 expression in porcine mitral VICs. While upstream, we provide insights to show that SMA is regulated by mechanical tension in VICs to promote changes in ECM homeostasis. Conclusions: Together, our data show that in VICs, SMA, an actin binding protein, is important for mediating ECM remodeling associated with phenotypes observed in myxomatous degeneration, and its expression is regulated by mechanical tension. These novel insights could inform the development of future non-surgical therapeutics to halt the progression of mitral valve degeneration thereby avoiding end-stage prolapse. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Article
Dynamic Expression Profiles of β-Catenin during Murine Cardiac Valve Development
J. Cardiovasc. Dev. Dis. 2020, 7(3), 31; https://doi.org/10.3390/jcdd7030031 - 17 Aug 2020
Cited by 1 | Viewed by 1090
Abstract
β-catenin has been widely studied in many animal and organ systems across evolution, and gain or loss of function has been linked to a number of human diseases. Yet fundamental knowledge regarding its protein expression and localization remains poorly described. Thus, we sought [...] Read more.
β-catenin has been widely studied in many animal and organ systems across evolution, and gain or loss of function has been linked to a number of human diseases. Yet fundamental knowledge regarding its protein expression and localization remains poorly described. Thus, we sought to define whether there was a temporal and cell-specific regulation of β-catenin activities that correlate with distinct cardiac morphological events. Our findings indicate that activated nuclear β-catenin is primarily evident early in gestation. As development proceeds, nuclear β-catenin is down-regulated and becomes restricted to the membrane in a subset of cardiac progenitor cells. After birth, little β-catenin is detected in the heart. The co-expression of β-catenin with its main transcriptional co-factor, Lef1, revealed that Lef1 and β-catenin expression domains do not extensively overlap in the cardiac valves. These data indicate mutually exclusive roles for Lef1 and β-catenin in most cardiac cell types during development. Additionally, these data indicate diverse functions for β-catenin within the nucleus and membrane depending on cell type and gestational timing. Cardiovascular studies should take into careful consideration both nuclear and membrane β-catenin functions and their potential contributions to cardiac development and disease. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Review

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Review
Collagen Fibrillogenesis in the Mitral Valve: It’s a Matter of Compliance
J. Cardiovasc. Dev. Dis. 2021, 8(8), 98; https://doi.org/10.3390/jcdd8080098 - 20 Aug 2021
Viewed by 475
Abstract
Collagen fibers are essential structural components of mitral valve leaflets, their tension apparatus (chordae tendineae), and the associated papillary muscles. Excess or lack of collagen fibers in the extracellular matrix (ECM) in any of these structures can adversely affect mitral valve function. The [...] Read more.
Collagen fibers are essential structural components of mitral valve leaflets, their tension apparatus (chordae tendineae), and the associated papillary muscles. Excess or lack of collagen fibers in the extracellular matrix (ECM) in any of these structures can adversely affect mitral valve function. The organization of collagen fibers provides a sophisticated framework that allows for unidirectional blood flow during the precise opening and closing of this vital heart valve. Although numerous ECM molecules are essential for the differentiation, growth, and homeostasis of the mitral valve (e.g., elastic fibers, glycoproteins, and glycans), collagen fibers are key to mitral valve integrity. Besides the inert structural components of the tissues, collagen fibers are dynamic structures that drive outside-to-inside cell signaling, which informs valvular interstitial cells (VICs) present within the tissue environment. Diversity of collagen family members and the closely related collagen-like triple helix-containing proteins found in the mitral valve, will be discussed in addition to how defects in these proteins may lead to valve disease. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Review
Characterization of Degenerative Mitral Valve Disease: Differences between Fibroelastic Deficiency and Barlow’s Disease
J. Cardiovasc. Dev. Dis. 2021, 8(2), 23; https://doi.org/10.3390/jcdd8020023 - 22 Feb 2021
Cited by 2 | Viewed by 910
Abstract
Degenerative mitral valve disease causing mitral valve prolapse is the most common cause of primary mitral regurgitation, with two distinct phenotypes generally recognized with some major differences, i.e., fibroelastic deficiency (FED) and Barlow’s disease. The aim of this review was to describe the [...] Read more.
Degenerative mitral valve disease causing mitral valve prolapse is the most common cause of primary mitral regurgitation, with two distinct phenotypes generally recognized with some major differences, i.e., fibroelastic deficiency (FED) and Barlow’s disease. The aim of this review was to describe the main histological, clinical and echocardiographic features of patients with FED and Barlow’s disease, highlighting the differences in diagnosis, risk stratification and patient management, but also the still significant gaps in understanding the exact pathophysiology of these two phenotypes. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Review
Myxomatous Mitral Valve Disease with Mitral Valve Prolapse and Mitral Annular Disjunction: Clinical and Functional Significance of the Coincidence
J. Cardiovasc. Dev. Dis. 2021, 8(2), 9; https://doi.org/10.3390/jcdd8020009 - 24 Jan 2021
Cited by 1 | Viewed by 1137
Abstract
The morphological changes that occur in myxomatous mitral valve disease (MMVD) involve various components, ultimately leading to the impairment of mitral valve (MV) function. In this context, intrinsic mitral annular abnormalities are increasingly recognized, such as a mitral annular disjunction (MAD), a specific [...] Read more.
The morphological changes that occur in myxomatous mitral valve disease (MMVD) involve various components, ultimately leading to the impairment of mitral valve (MV) function. In this context, intrinsic mitral annular abnormalities are increasingly recognized, such as a mitral annular disjunction (MAD), a specific anatomical abnormality whereby there is a distinct separation between the mitral annulus and the left atrial wall and the basal portion of the posterolateral left ventricular myocardium. In recent years, several studies have suggested that MAD contributes to myxomatous degeneration of the mitral leaflets, and there is growing evidence that MAD is associated with ventricular arrhythmias and sudden cardiac death. In this review, the morphological characteristics of MAD and imaging tools for diagnosis will be described, and the clinical and functional aspects of the coincidence of MAD and myxomatous MVP will be discussed. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Review
Biology and Biomechanics of the Heart Valve Extracellular Matrix
J. Cardiovasc. Dev. Dis. 2020, 7(4), 57; https://doi.org/10.3390/jcdd7040057 - 16 Dec 2020
Cited by 5 | Viewed by 1187
Abstract
Heart valves are dynamic structures that, in the average human, open and close over 100,000 times per day, and 3 × 109 times per lifetime to maintain unidirectional blood flow. Efficient, coordinated movement of the valve structures during the cardiac cycle is [...] Read more.
Heart valves are dynamic structures that, in the average human, open and close over 100,000 times per day, and 3 × 109 times per lifetime to maintain unidirectional blood flow. Efficient, coordinated movement of the valve structures during the cardiac cycle is mediated by the intricate and sophisticated network of extracellular matrix (ECM) components that provide the necessary biomechanical properties to meet these mechanical demands. Organized in layers that accommodate passive functional movements of the valve leaflets, heart valve ECM is synthesized during embryonic development, and remodeled and maintained by resident cells throughout life. The failure of ECM organization compromises biomechanical function, and may lead to obstruction or leaking, which if left untreated can lead to heart failure. At present, effective treatment for heart valve dysfunction is limited and frequently ends with surgical repair or replacement, which comes with insuperable complications for many high-risk patients including aged and pediatric populations. Therefore, there is a critical need to fully appreciate the pathobiology of biomechanical valve failure in order to develop better, alternative therapies. To date, the majority of studies have focused on delineating valve disease mechanisms at the cellular level, namely the interstitial and endothelial lineages. However, less focus has been on the ECM, shown previously in other systems, to be a promising mechanism-inspired therapeutic target. Here, we highlight and review the biology and biomechanical contributions of key components of the heart valve ECM. Furthermore, we discuss how human diseases, including connective tissue disorders lead to aberrations in the abundance, organization and quality of these matrix proteins, resulting in instability of the valve infrastructure and gross functional impairment. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Review
Anatomy of Mitral Valve Complex as Revealed by Non-Invasive Imaging: Pathological, Surgical and Interventional Implications
J. Cardiovasc. Dev. Dis. 2020, 7(4), 49; https://doi.org/10.3390/jcdd7040049 - 04 Nov 2020
Cited by 2 | Viewed by 1108
Abstract
Knowledge of mitral valve (MV) anatomy has been accrued from anatomic specimens derived by cadavers, or from direct inspection during open heart surgery. However, today two-dimensional and three-dimensional transthoracic (2D/3D TTE) and transesophageal echocardiography (2D/3D TEE), computed tomography (CT) and cardiac magnetic resonance [...] Read more.
Knowledge of mitral valve (MV) anatomy has been accrued from anatomic specimens derived by cadavers, or from direct inspection during open heart surgery. However, today two-dimensional and three-dimensional transthoracic (2D/3D TTE) and transesophageal echocardiography (2D/3D TEE), computed tomography (CT) and cardiac magnetic resonance (CMR) provide images of the beating heart of unprecedented quality in both two and three-dimensional format. Indeed, over the last few years these non-invasive imaging techniques have been used for describing dynamic cardiac anatomy. Differently from the “dead” anatomy of anatomic specimens and the “static” anatomy observed during surgery, they have the unique ability of showing “dynamic” images from beating hearts. The “dynamic” anatomy gives us a better awareness, as any single anatomic arrangement corresponds perfectly to a specific function. Understanding normal anatomical aspects of MV apparatus is of a paramount importance for a correct interpretation of the wide spectrum of patho-morphological MV diseases. This review illustrates the anatomy of MV as revealed by non-invasive imaging describing physiological, pathological, surgical and interventional implications related to specific anatomical features of the MV complex. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Other

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Case Report
Malignant Arrhythmic Mitral Valve Prolapse: A Continuum of Clinical Challenges from Diagnosis to Risk Stratification and Patient Management
by , and
J. Cardiovasc. Dev. Dis. 2021, 8(1), 2; https://doi.org/10.3390/jcdd8010002 - 29 Dec 2020
Viewed by 808
Abstract
Mitral valve prolapse (MVP) is a common valvular disease, which may remain a benign condition for a long period of time. However, some patients experience malignant ventricular arrhythmias and sudden cardiac death (SCD). It is still largely unknown how to risk-stratify these patients, [...] Read more.
Mitral valve prolapse (MVP) is a common valvular disease, which may remain a benign condition for a long period of time. However, some patients experience malignant ventricular arrhythmias and sudden cardiac death (SCD). It is still largely unknown how to risk-stratify these patients, and no specific recommendations have been proposed to help the clinical decision-making. We present the case of a young man whose first clinical presentation was an out-of-hospital cardiac arrest and was subsequently diagnosed with MVP. We highlighted the possible risk factors for SCD and the challenges in the clinical management of these patients. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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Case Report
Early Basal Cuspal Tear of a Porcine Bioprosthetic Mitral Valve Causing Massive Mitral Regurgitation
J. Cardiovasc. Dev. Dis. 2020, 7(4), 52; https://doi.org/10.3390/jcdd7040052 - 06 Nov 2020
Viewed by 750
Abstract
Although porcine mitral bioprostheses provide predictably good long-term outcomes, unexpected leaflet tears leading to abrupt haemodynamic changes may occur. Here, we report on a patient who was presented with acute dyspnea due to a cuspal tear of a porcine bioprosthetic mitral valve causing [...] Read more.
Although porcine mitral bioprostheses provide predictably good long-term outcomes, unexpected leaflet tears leading to abrupt haemodynamic changes may occur. Here, we report on a patient who was presented with acute dyspnea due to a cuspal tear of a porcine bioprosthetic mitral valve causing severe mitral regurgitation. Her condition was subsequently complicated by a systemic infection, probably pneumonia, and was successfully managed with an urgent redo-mitral valve replacement. Full article
(This article belongs to the Special Issue Mitral Valve Development and Disease)
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