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Levy S, Sharaf Dabbagh G, Giudicessi JR, Haqqani H, Khanji MY, Obeng-Gyimah E, Betts MN, Ricci F, Asatryan B, Bouatia-Naji N, Nazarian S, Chahal CAA. Genetic mechanisms underlying arrhythmogenic mitral valve prolapse: Current and future perspectives. Heart Rhythm O2 2023; 4:581-591. [PMID: 37744942 PMCID: PMC10513923 DOI: 10.1016/j.hroo.2023.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/26/2023] Open
Abstract
Mitral valve prolapse (MVP) is a heart valve disease that is often familial, affecting 2%-3% of the general population. MVP with or without mitral regurgitation can be associated with an increased risk of ventricular arrhythmias and sudden cardiac death (SCD). Research on familial MVP has specifically focused on genetic factors, which may explain the heritable component of the disease estimated to be present in 20%-35%. Furthermore, the structural and electrophysiological substrates underlying SCD/ventricular arrhythmia risk in MVP have been studied postmortem and in the electrophysiology laboratory, respectively. Understanding how familial MVP and rhythm disorders are related may help patients with MVP by individualizing risk and working to develop effective management strategies. This contemporary, state-of-the-art, expert review focuses on genetic factors and familial components that underlie MVP and arrhythmia and encapsulates clinical, genetic, and electrophysiological issues that should be the objectives of future research.
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Affiliation(s)
- Sydney Levy
- Byram Hills High School, Armonk, New York
- Harvard College, Cambridge, Massachusetts
| | - Ghaith Sharaf Dabbagh
- Center for Inherited Cardiovascular Diseases, WellSpan Health, Lancaster, Pennsylvania
- Division of Cardiovascular Medicine, University of Michigan, Ann Arbor, Michigan
| | - John R. Giudicessi
- Divisions of Heart Rhythm Services and Circulatory Failure, Departments of Cardiovascular Medicine, Molecular Pharmacology, and Experimental Therapeutics, Mayo Clinic, Rochester, Minnesota
| | | | - Mohammed Y. Khanji
- Byram Hills High School, Armonk, New York
- NIHR Barts Biomedical Research Centre, William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
- Newham University Hospital, Barts Health NHS Trust, London, United Kingdom
| | - Edmond Obeng-Gyimah
- Clinical Cardiac Electrophysiology, VT and Complex Ablation Program, WellSpan Health, York, Pennsylvania
| | - Megan N. Betts
- Center for Inherited Cardiovascular Diseases, WellSpan Health, Lancaster, Pennsylvania
| | - Fabrizio Ricci
- Department of Neuroscience, Imaging and Clinical Sciences, “G. d'Annunzio” University of Chieti-Pescara, Chieti, Italy
- Department of Clinical Sciences, Lund University, Malmö, Sweden
- Fondazione Villaserena per la Ricerca, Città Sant’Angelo, Italy
| | - Babken Asatryan
- Department of Medicine, Division of Cardiology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | | | - Saman Nazarian
- Division of Cardiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania
| | - C. Anwar A. Chahal
- Center for Inherited Cardiovascular Diseases, WellSpan Health, Lancaster, Pennsylvania
- Barts Heart Centre, Barts Health NHS Trust, London, West Smithfield, United Kingdom
- Cardiac Electrophysiology, Cardiovascular Division, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania
- Department of Cardiovascular Medicine, Mayo Clinic, Rochester, Minnesota
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2
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Delwarde C, Capoulade R, Mérot J, Le Scouarnec S, Bouatia-Naji N, Yu M, Huttin O, Selton-Suty C, Sellal JM, Piriou N, Schott JJ, Dina C, Le Tourneau T. Genetics and pathophysiology of mitral valve prolapse. Front Cardiovasc Med 2023; 10:1077788. [PMID: 36873395 PMCID: PMC9978496 DOI: 10.3389/fcvm.2023.1077788] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2022] [Accepted: 01/23/2023] [Indexed: 02/18/2023] Open
Abstract
Mitral valve prolapse (MVP) is a common condition affecting 2-3% of the general population, and the most complex form of valve pathology, with a complication rate up to 10-15% per year in advanced stages. Complications include mitral regurgitation which can lead to heart failure and atrial fibrillation, but also life-threatening ventricular arrhythmia and cardiovascular death. Sudden death has been recently brought to the forefront of MVP disease, increasing the complexity of management and suggesting that MVP condition is not properly understood. MVP can occur as part of syndromic conditions such as Marfan syndrome, but the most common form is non-syndromic, isolated or familial. Although a specific X-linked form of MVP was initially identified, autosomal dominant inheritance appears to be the primary mode of transmission. MVP can be stratified into myxomatous degeneration (Barlow), fibroelastic deficiency, and Filamin A-related MVP. While FED is still considered a degenerative disease associated with aging, myxomatous MVP and FlnA-MVP are recognized as familial pathologies. Deciphering genetic defects associated to MVP is still a work in progress; although FLNA, DCHS1, and DZIP1 have been identified as causative genes in myxomatous forms of MVP thanks to familial approaches, they explain only a small proportion of MVP. In addition, genome-wide association studies have revealed the important role of common variants in the development of MVP, in agreement with the high prevalence of this condition in the population. Furthermore, a potential genetic link between MVP and ventricular arrhythmia or a specific type of cardiomyopathy is considered. Animal models that allow to advance in the genetic and pathophysiological knowledge of MVP, and in particular those that can be easily manipulated to express a genetic defect identified in humans are detailed. Corroborated by genetic data and animal models, the main pathophysiological pathways of MVP are briefly addressed. Finally, genetic counseling is considered in the context of MVP.
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Affiliation(s)
- Constance Delwarde
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
| | - Romain Capoulade
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
| | - Jean Mérot
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
| | - Solena Le Scouarnec
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
| | | | - Mengyao Yu
- Human Phenome Institute, Fudan University, Shanghai, China
| | - Olivier Huttin
- Service de Cardiologie, Institut Lorrain du Coeur et des Vaisseaux Louis Mathieu, CHU de Nancy, Nancy, France
| | - Christine Selton-Suty
- Service de Cardiologie, Institut Lorrain du Coeur et des Vaisseaux Louis Mathieu, CHU de Nancy, Nancy, France
| | - Jean-Marc Sellal
- Service de Cardiologie, Institut Lorrain du Coeur et des Vaisseaux Louis Mathieu, CHU de Nancy, Nancy, France
| | - Nicolas Piriou
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
| | - Jean-Jacques Schott
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
| | - Christian Dina
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
| | - Thierry Le Tourneau
- Nantes Université, CHU Nantes, CNRS, INSERM, L'institut du Thorax, Nantes, France
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3
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Delwarde C, Toquet C, Aumond P, Kayvanjoo AH, Foucal A, Le Vely B, Baudic M, Lauzier B, Blandin S, Véziers J, Paul-Gilloteaux P, Lecointe S, Baron E, Massaiu I, Poggio P, Rémy S, Anegon I, Le Marec H, Monassier L, Schott JJ, Mass E, Barc J, Le Tourneau T, Merot J, Capoulade R. Multimodality imaging and transciptomics to phenotype mitral valve dystrophy in a unique knock-in Filamin-A rat model. Cardiovasc Res 2022; 119:759-771. [PMID: 36001550 DOI: 10.1093/cvr/cvac136] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2022] [Revised: 06/29/2022] [Accepted: 07/26/2022] [Indexed: 11/12/2022] Open
Abstract
AIMS Degenerative mitral valve dystrophy (MVD) leading to mitral valve prolapse is the most frequent form of MV disease, and there is currently no pharmacological treatment available. The limited understanding of the pathophysiological mechanisms leading to MVD limits our ability to identify therapeutic targets. This study aimed to reveal the main pathophysiological pathways involved in MVD via the multimodality imaging and transcriptomic analysis of the new and unique Knock-In (KI) rat model for the FlnA-P637Q mutation associated-MVD. METHODS AND RESULTS WT and KI rats were evaluated morphologically, functionally, and histologically between 3-week-old and 3-to-6-month-old based on Doppler echocardiography, 3D micro-computed tomography (microCT), and standard histology. RNA-sequencing and Assay for Transposase-Accessible Chromatin (ATAC-seq) were performed on 3-week-old WT and KI mitral valves and valvular cells, respectively, to highlight the main signaling pathways associated with MVD. Echocardiographic exploration confirmed MV elongation (2.0 ± 0.1 mm versus 1.8 ± 0.1, p = 0.001), as well as MV thickening and prolapse in KI animals compared to WT at 3 weeks. 3D MV volume quantified by microCT was significantly increased in KI animals (+58% versus WT, p = 0.02). Histological analyses revealed a myxomatous remodeling in KI MV characterized by proteoglycans accumulation. A persistent phenotype was observed in adult KI rats. Signaling pathways related to extracellular matrix homeostasis, response to molecular stress, epithelial cell migration, endothelial to mesenchymal transition, chemotaxis and immune cell migration, were identified based on RNA-seq analysis. ATAC-seq analysis points to the critical role of TGF-β and inflammation in the disease. CONCLUSION The KI FlnA-P637Q rat model mimics human myxomatous mitral valve dystrophy, offering a unique opportunity to decipher pathophysiological mechanisms related to this disease. Extracellular matrix organization, epithelial cell migration, response to mechanical stress, and a central contribution of immune cells are highlighted as the main signaling pathways leading to myxomatous mitral valve dystrophy. Our findings pave the road to decipher underlying molecular mechanisms and the specific role of distinct cell populations in this context.
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Affiliation(s)
- Constance Delwarde
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Claire Toquet
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Pascal Aumond
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Amir Hossein Kayvanjoo
- Developmental Biology of the Immune System, Life & Medical Sciences (LIMES) Institute, University of Bonn; 53115 Bonn, Germany
| | - Adrien Foucal
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Benjamin Le Vely
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Manon Baudic
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Benjamin Lauzier
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Stéphanie Blandin
- Nantes Université, CHU Nantes, Inserm, CNRS, SFR Santé, Inserm UMS 016, CNRS UAR 3556, F-44000 Nantes, France
| | - Joëlle Véziers
- INSERM, UMR 1229, RMeS, CHU Nantes PHU4 OTONN, Nantes Univ, Nantes, France
| | - Perrine Paul-Gilloteaux
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France.,Nantes Université, CHU Nantes, Inserm, CNRS, SFR Santé, Inserm UMS 016, CNRS UAR 3556, F-44000 Nantes, France
| | - Simon Lecointe
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Estelle Baron
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | | | - Paolo Poggio
- Centro Cardiologico Monzino IRCCS, Milano, Italy
| | - Séverine Rémy
- INSERM UMR 1064-CR2TI, Transgenic Rats ImmunoPhenomic, Nantes, France
| | - Ignacio Anegon
- INSERM UMR 1064-CR2TI, Transgenic Rats ImmunoPhenomic, Nantes, France
| | - Hervé Le Marec
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Laurent Monassier
- Laboratoire de Pharmacologie et Toxicologie NeuroCardiovasculaire UR7296, Université de Strasbourg, Strasbourg, France
| | - Jean Jacques Schott
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Elvira Mass
- Developmental Biology of the Immune System, Life & Medical Sciences (LIMES) Institute, University of Bonn; 53115 Bonn, Germany
| | - Julien Barc
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Thierry Le Tourneau
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Jean Merot
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
| | - Romain Capoulade
- Nantes Université, CHU Nantes, CNRS, INSERM, l'institut du thorax, F-44000 Nantes, France
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4
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Morningstar JE, Nieman A, Wang C, Beck T, Harvey A, Norris RA. Mitral Valve Prolapse and Its Motley Crew-Syndromic Prevalence, Pathophysiology, and Progression of a Common Heart Condition. J Am Heart Assoc 2021; 10:e020919. [PMID: 34155898 PMCID: PMC8403286 DOI: 10.1161/jaha.121.020919] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 04/21/2021] [Indexed: 01/01/2023]
Abstract
Mitral valve prolapse (MVP) is a commonly occurring heart condition defined by enlargement and superior displacement of the mitral valve leaflet(s) during systole. Although commonly seen as a standalone disorder, MVP has also been described in case reports and small studies of patients with various genetic syndromes. In this review, we analyzed the prevalence of MVP within syndromes where an association to MVP has previously been reported. We further discussed the shared biological pathways that cause MVP in these syndromes, as well as how MVP in turn causes a diverse array of cardiac and noncardiac complications. We found 105 studies that identified patients with mitral valve anomalies within 18 different genetic, developmental, and connective tissue diseases. We show that some disorders previously believed to have an increased prevalence of MVP, including osteogenesis imperfecta, fragile X syndrome, Down syndrome, and Pseudoxanthoma elasticum, have few to no studies that use up-to-date diagnostic criteria for the disease and therefore may be overestimating the prevalence of MVP within the syndrome. Additionally, we highlight that in contrast to early studies describing MVP as a benign entity, the clinical course experienced by patients can be heterogeneous and may cause significant cardiovascular morbidity and mortality. Currently only surgical correction of MVP is curative, but it is reserved for severe cases in which irreversible complications of MVP may already be established; therefore, a review of clinical guidelines to allow for earlier surgical intervention may be warranted to lower cardiovascular risk in patients with MVP.
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Affiliation(s)
- Jordan E. Morningstar
- Department of Regenerative Medicine and Cell BiologyMedical University of South CarolinaCharlestonSC
| | - Annah Nieman
- Department of Regenerative Medicine and Cell BiologyMedical University of South CarolinaCharlestonSC
| | - Christina Wang
- Department of Regenerative Medicine and Cell BiologyMedical University of South CarolinaCharlestonSC
| | - Tyler Beck
- Department of Regenerative Medicine and Cell BiologyMedical University of South CarolinaCharlestonSC
| | - Andrew Harvey
- Department of Regenerative Medicine and Cell BiologyMedical University of South CarolinaCharlestonSC
| | - Russell A. Norris
- Department of Regenerative Medicine and Cell BiologyMedical University of South CarolinaCharlestonSC
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5
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Misra S, Ghatak S, Moreno-Rodriguez RA, Norris RA, Hascall VC, Markwald RR. Periostin/Filamin-A: A Candidate Central Regulatory Axis for Valve Fibrogenesis and Matrix Compaction. Front Cell Dev Biol 2021; 9:649862. [PMID: 34150753 PMCID: PMC8209548 DOI: 10.3389/fcell.2021.649862] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 04/07/2021] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Discoveries in the identification of transcription factors, growth factors and extracellular signaling molecules have led to the detection of downstream targets that modulate valvular tissue organization that occurs during development, aging, or disease. Among these, matricellular protein, periostin, and cytoskeletal protein filamin A are highly expressed in developing heart valves. The phenotype of periostin null indicates that periostin promotes migration, survival, and differentiation of valve interstitial cushion cells into fibroblastic lineages necessary for postnatal valve remodeling/maturation. Genetically inhibiting filamin A expression in valve interstitial cushion cells mirrored the phenotype of periostin nulls, suggesting a molecular interaction between these two proteins resulted in poorly remodeled valve leaflets that might be prone to myxomatous over time. We examined whether filamin A has a cross-talk with periostin/signaling that promotes remodeling of postnatal heart valves into mature leaflets. RESULTS We have previously shown that periostin/integrin-β1 regulates Pak1 activation; here, we revealed that the strong interaction between Pak1 and filamin A proteins was only observed after stimulation of VICs with periostin; suggesting that periostin/integrin-β-mediated interaction between FLNA and Pak1 may have a functional role in vivo. We found that FLNA phosphorylation (S2152) is activated by Pak1, and this interaction was observed after stimulation with periostin/integrin-β1/Cdc42/Rac1 signaling; consequently, FLNA binding to Pak1 stimulates its kinase activity. Patients with floppy and/or prolapsed mitral valves, when genetically screened, were found to have point mutations in the filamin A gene at P637Q and G288R. Expression of either of these filamin A mutants failed to increase the magnitude of filamin A (S2152) expression, Pak1-kinase activity, actin polymerization, and differentiation of VICs into mature mitral valve leaflets in response to periostin signaling. CONCLUSION PN-stimulated bidirectional interaction between activated FLNA and Pak1 is essential for actin cytoskeletal reorganization and the differentiation of immature VICs into mature valve leaflets.
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Affiliation(s)
- Suniti Misra
- Department of Biochemistry and Molecular Biology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States
| | - Shibnath Ghatak
- Department of Biochemistry and Molecular Biology, Hollings Cancer Center, Medical University of South Carolina, Charleston, SC, United States
| | - Ricardo A. Moreno-Rodriguez
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, United States
| | - Russell A. Norris
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, United States
| | - Vincent C. Hascall
- Department of Biomedical Engineering/ND20, Cleveland Clinic, Cleveland, OH, United States
| | - Roger R. Markwald
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, United States
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6
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Zhou J, Kang X, An H, Lv Y, Liu X. The function and pathogenic mechanism of filamin A. Gene 2021; 784:145575. [PMID: 33737122 DOI: 10.1016/j.gene.2021.145575] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 03/04/2021] [Accepted: 03/08/2021] [Indexed: 12/13/2022]
Abstract
Filamin A(FLNa) is an actin-binding protein, which participates in the formation of the cytoskeleton, anchors a variety of proteins in the cytoskeleton and regulates cell adhesion and migration. It is involved in signal transduction, cell proliferation and differentiation, pseudopodia formation, vesicle transport, tumor resistance and genetic diseases by binding with interacting proteins. In order to fully elucidate the structure, function and pathogenesis of FLNa, we summarized all substances which directly or indirectly act on FLNa so far, upstream and downstream targets which having effect on it, signaling pathways and their functions. It also recorded the expression and effect of FLNa in different diseases, including hereditary disease and tumors.
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Affiliation(s)
- Jie Zhou
- Department of Oncology, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361000, Fujian, China.
| | - Xinmei Kang
- Department of Oncology, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361000, Fujian, China.
| | - Hanxiang An
- Department of Oncology, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361000, Fujian, China.
| | - Yun Lv
- Department of Oncology, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361000, Fujian, China.
| | - Xin Liu
- Department of Oncology, Xiang'an Hospital of Xiamen University, School of Medicine, Xiamen University, Xiamen 361000, Fujian, China.
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7
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van Wijngaarden AL, Kruithof BPT, Vinella T, Barge-Schaapveld DQCM, Ajmone Marsan N. Characterization of Degenerative Mitral Valve Disease: Differences between Fibroelastic Deficiency and Barlow's Disease. J Cardiovasc Dev Dis 2021; 8:23. [PMID: 33671724 PMCID: PMC7926852 DOI: 10.3390/jcdd8020023] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2021] [Revised: 02/17/2021] [Accepted: 02/19/2021] [Indexed: 12/18/2022] Open
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 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.
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Affiliation(s)
- Aniek L. van Wijngaarden
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (A.L.v.W.); (B.P.T.K.)
| | - Boudewijn P. T. Kruithof
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (A.L.v.W.); (B.P.T.K.)
| | - Tommaso Vinella
- Faculty of Medicine, University of Southampton, Southampton SO17 1BJ, UK;
| | | | - Nina Ajmone Marsan
- Department of Cardiology, Leiden University Medical Center, Albinusdreef 2, 2333 ZA Leiden, The Netherlands; (A.L.v.W.); (B.P.T.K.)
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8
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Van Berendoncks A, McGhie J, Heidbuchel H, Roos-Hesselink JW. Repetitive out of hospital cardiac arrests following pregnancy: a case report of an unfortunate presentation of mitral annular disjunction. Eur Heart J Case Rep 2020; 4:1-7. [PMID: 32974487 PMCID: PMC7501944 DOI: 10.1093/ehjcr/ytaa135] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 10/17/2019] [Accepted: 04/29/2020] [Indexed: 11/12/2022]
Abstract
BACKGROUND Mitral annular disjunction (MAD) is an under-recognized cause of arrhythmic sudden cardiac death, especially in young women. The relation between MAD and the occurrence of arrhythmia during pregnancy has not yet been explored. We would like to stress the importance of careful echocardiographic examination and the vulnerable peripartum period. CASE SUMMARY A 29-year-old woman survived an out of hospital cardiac arrest 4 months after delivery of her first child. The diagnosis was not clear and an implantable cardioverter-defibrillator (ICD) as secondary prevention was implanted. Her second pregnancy and delivery were uneventful. The 12-lead electrocardiogram demonstrated sinus rhythm with right bundle branch block, ventricular extra systoles (premature ventricular contractions), and a right superior axis, i.e. origin in the inferolateral basal left ventricle. Transthoracic 2D echocardiography showed myxomatous mitral valve disease with moderate mitral valve insufficiency with normal left and right heart dimensions and function. However, 4 weeks after delivery she experienced a sudden syncope at home. Implantable cardioverter-defibrillator reading revealed primary ventricular fibrillation, induced by a ventricular premature beat (VPB), terminated with a successful ICD shock. A frame-by-frame echocardiographic analysis of the mitral valve using biplane echocardiographic analysis allowed diagnosis of MAD with detachment of the root of the annulus from the posterolateral ventricular myocardium during systole. CONCLUSION Mitral annular disjunction is an under-recognized cause of arrhythmic sudden cardiac death. Biplane echocardiographic analysis of the mitral annulus can identify MAD and as such may help for risk stratification and sudden cardiac death prevention. Careful follow-up is necessary especially during pregnancy and the postpartum period.
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Affiliation(s)
- An Van Berendoncks
- Department of Cardiology, Erasmus Medical Centre, Congenital heart disease RG4, PO Box 2040, 3000 CA, Rotterdam, the Netherlands.,Department of Cardiology, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium.,Department of Cardiovascular Diseases, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Jackie McGhie
- Department of Cardiology, Erasmus Medical Centre, Congenital heart disease RG4, PO Box 2040, 3000 CA, Rotterdam, the Netherlands
| | - Hein Heidbuchel
- Department of Cardiology, Antwerp University Hospital, Wilrijkstraat 10, 2650 Edegem, Belgium.,Department of Cardiovascular Diseases, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium
| | - Jolien W Roos-Hesselink
- Department of Cardiology, Erasmus Medical Centre, Congenital heart disease RG4, PO Box 2040, 3000 CA, Rotterdam, the Netherlands
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9
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Fulmer D, Toomer KA, Glover J, Guo L, Moore K, Moore R, Stairley R, Gensemer C, Abrol S, Rumph MK, Emetu F, Lipschutz JH, McDowell C, Bian J, Wang C, Beck T, Wessels A, Renault MA, Norris RA. Desert hedgehog-primary cilia cross talk shapes mitral valve tissue by organizing smooth muscle actin. Dev Biol 2020; 463:26-38. [PMID: 32151560 DOI: 10.1016/j.ydbio.2020.03.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2019] [Revised: 02/27/2020] [Accepted: 03/02/2020] [Indexed: 01/01/2023]
Abstract
Non-syndromic mitral valve prolapse (MVP) is the most common heart valve disease affecting 2.4% of the population. Recent studies have identified genetic defects in primary cilia as causative to MVP, although the mechanism of their action is currently unknown. Using a series of gene inactivation approaches, we define a paracrine mechanism by which endocardially-expressed Desert Hedgehog (DHH) activates primary cilia signaling on neighboring valve interstitial cells. High-resolution imaging and functional assays show that DHH de-represses smoothened at the primary cilia, resulting in kinase activation of RAC1 through the RAC1-GEF, TIAM1. Activation of this non-canonical hedgehog pathway stimulates α-smooth actin organization and ECM remodeling. Genetic or pharmacological perturbation of this pathway results in enlarged valves that progress to a myxomatous phenotype, similar to valves seen in MVP patients. These data identify a potential molecular origin for MVP as well as establish a paracrine DHH-primary cilium cross-talk mechanism that is likely applicable across developmental tissue types.
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Affiliation(s)
- Diana Fulmer
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Katelynn A Toomer
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA; Department of Genetic Medicine, John Hopkins, Baltimore, MD, USA
| | - Janiece Glover
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Lilong Guo
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Kelsey Moore
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Reece Moore
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Rebecca Stairley
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Cortney Gensemer
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Sameer Abrol
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Mary Kate Rumph
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Faith Emetu
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Joshua H Lipschutz
- Department of Medicine, Medical University of South Carolina, Charleston, SC, USA
| | - Colin McDowell
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Justin Bian
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Christina Wang
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Tyler Beck
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | - Andy Wessels
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA
| | | | - Russell A Norris
- Department of Regenerative Medicine and Cell Biology, Medical University of South Carolina, Charleston, SC, USA; Department of Medicine, Medical University of South Carolina, Charleston, SC, USA.
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10
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Haataja TJK, Capoulade R, Lecointe S, Hellman M, Merot J, Permi P, Pentikäinen U. Critical Structural Defects Explain Filamin A Mutations Causing Mitral Valve Dysplasia. Biophys J 2019; 117:1467-1475. [PMID: 31542223 DOI: 10.1016/j.bpj.2019.08.032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Revised: 08/15/2019] [Accepted: 08/28/2019] [Indexed: 11/16/2022] Open
Abstract
Mitral valve diseases affect ∼3% of the population and are the most common reasons for valvular surgery because no drug-based treatments exist. Inheritable genetic mutations have now been established as the cause of mitral valve insufficiency, and four different missense mutations in the filamin A gene (FLNA) have been found in patients suffering from nonsyndromic mitral valve dysplasia (MVD). The filamin A (FLNA) protein is expressed, in particular, in endocardial endothelia during fetal valve morphogenesis and is key in cardiac development. The FLNA-MVD-causing mutations are clustered in the N-terminal region of FLNA. How the mutations in FLNA modify its structure and function has mostly remained elusive. In this study, using NMR spectroscopy and interaction assays, we investigated FLNA-MVD-causing V711D and H743P mutations. Our results clearly indicated that both mutations almost completely destroyed the folding of the FLNA5 domain, where the mutation is located, and also affect the folding of the neighboring FLNA4 domain. The structure of the neighboring FLNA6 domain was not affected by the mutations. These mutations also completely abolish FLNA's interactions with protein tyrosine phosphatase nonreceptor type 12, which has been suggested to contribute to the pathogenesis of FLNA-MVD. Taken together, our results provide an essential structural and molecular framework for understanding the molecular bases of FLNA-MVD, which is crucial for the development of new therapies to replace surgery.
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Affiliation(s)
- Tatu J K Haataja
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland; Institute of Biomedicine, University of Turku, Turku, Finland; Turku Bioscience Centre, University of Turku, 20520 Turku, Finland
| | - Romain Capoulade
- l'institut du thorax, INSERM, CNRS, University of Nantes, Nantes, France
| | - Simon Lecointe
- l'institut du thorax, INSERM, CNRS, University of Nantes, Nantes, France
| | - Maarit Hellman
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland; Department of Chemistry and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Jean Merot
- l'institut du thorax, INSERM, CNRS, University of Nantes, Nantes, France
| | - Perttu Permi
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland; Department of Chemistry and Nanoscience Center, University of Jyväskylä, Jyväskylä, Finland
| | - Ulla Pentikäinen
- Institute of Biomedicine, University of Turku, Turku, Finland; Turku Bioscience Centre, University of Turku, 20520 Turku, Finland.
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11
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Haataja TJK, Bernardi RC, Lecointe S, Capoulade R, Merot J, Pentikäinen U. Non-syndromic Mitral Valve Dysplasia Mutation Changes the Force Resilience and Interaction of Human Filamin A. Structure 2018; 27:102-112.e4. [PMID: 30344108 DOI: 10.1016/j.str.2018.09.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 07/24/2018] [Accepted: 09/18/2018] [Indexed: 01/03/2023]
Abstract
Filamin A (FLNa), expressed in endocardial endothelia during fetal valve morphogenesis, is key in cardiac development. Missense mutations in FLNa cause non-syndromic mitral valve dysplasia (FLNA-MVD). Here, we aimed to reveal the currently unknown underlying molecular mechanism behind FLNA-MVD caused by the FLNa P637Q mutation. The solved crystal structure of the FLNa3-5 P637Q revealed that this mutation causes only minor structural changes close to mutation site. These changes were observed to significantly affect FLNa's ability to transmit cellular force and to interact with its binding partner. The performed steered molecular dynamics simulations showed that significantly lower forces are needed to split domains 4 and 5 in FLNA-MVD than with wild-type FLNa. The P637Q mutation was also observed to interfere with FLNa's interactions with the protein tyrosine phosphatase PTPN12. Our results provide a crucial step toward understanding the molecular bases behind FLNA-MVD, which is critical for the development of drug-based therapeutics.
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Affiliation(s)
- Tatu J K Haataja
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, 40014 Jyväskylä, Finland
| | - Rafael C Bernardi
- Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Simon Lecointe
- L'institut du Thorax, INSERM, CNRS, UNIV Nantes, Nantes, France
| | | | - Jean Merot
- L'institut du Thorax, INSERM, CNRS, UNIV Nantes, Nantes, France
| | - Ulla Pentikäinen
- Department of Biological and Environmental Science and Nanoscience Center, University of Jyväskylä, 40014 Jyväskylä, Finland; Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA; Institute of Biomedicine, University of Turku, 20520 Turku, Finland; Turku Centre for Biotechnology, University of Turku, 20520 Turku, Finland.
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12
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Toomer K, Sauls K, Fulmer D, Guo L, Moore K, Glover J, Stairley R, Bischoff J, Levine RA, Norris RA. Filamin-A as a Balance between Erk/Smad Activities During Cardiac Valve Development. Anat Rec (Hoboken) 2018; 302:117-124. [PMID: 30288957 PMCID: PMC6312478 DOI: 10.1002/ar.23911] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Revised: 01/30/2018] [Accepted: 02/21/2018] [Indexed: 11/10/2022]
Abstract
Mitral valve prolapse (MVP) affects 2.4% of the population and has poorly understood etiology. Recent genetic studies have begun to unravel the complexities of MVP and through these efforts, mutations in the FLNA (Filamin-A) gene were identified as disease causing. Our in vivo and in vitro studies have validated these genetic findings and have revealed FLNA as a central regulator of valve morphogenesis. The mechanisms by which FLNA mutations result in myxomatous mitral valve disease are currently unknown, but may involve proteins previously associated with mutated regions of the FLNA protein, such as the small GTPase signaling protein, R-Ras. Herein, we report that Filamin-A is required for R-Ras expression and activation of the Ras-Mek-Erk pathway. Loss of the Ras/Erk pathway correlated with hyperactivation of pSmad2/3, increased extracellular matrix (ECM) production and enlarged mitral valves. Analyses of integrin receptors in the mitral valve revealed that Filamin-A was required for β1-integrin expression and provided a potential mechanism for impaired ECM compaction and valve enlargement. Our data support Filamin-A as a protein that regulates the balance between Erk and Smad activation and an inability of Filamin-A deficient valve interstitial cells to effectively remodel the increased ECM production through a β1-integrin mechanism. As a consequence, loss of Filamin-A function results in increased ECM production and generation of a myxomatous phenotype characterized by improperly compacted mitral valve tissue. Anat Rec, 302:117-124, 2019. © 2018 Wiley Periodicals, Inc.
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Affiliation(s)
- Katelynn Toomer
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Kimberly Sauls
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Diana Fulmer
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Lilong Guo
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Kelsey Moore
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Janiece Glover
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Rebecca Stairley
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
| | - Joyce Bischoff
- Vascular Biology Program and Department of Surgery, Boston Children's Hospital and Harvard Medical School, Boston, Massachusetts
| | - Robert A Levine
- Cardiac Ultrasound Laboratory, Cardiology Division, Massachusetts General Hospital Research Institute, Harvard Medical School, Boston, Massachusetts
| | - Russell A Norris
- Cardiovascular Developmental Biology Center, Department of Regenerative Medicine and Cell Biology, College of Medicine, Children's Research Institute, Medical University of South Carolina, Charleston, South Carolina
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13
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Serotonin contribution to cardiac valve degeneration: new insights for novel therapies? Pharmacol Res 2018; 140:33-42. [PMID: 30208338 DOI: 10.1016/j.phrs.2018.09.009] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 09/07/2018] [Accepted: 09/07/2018] [Indexed: 01/13/2023]
Abstract
Heart valve disease (HVD) is a complex entity made by different pathological processes that ultimately lead to the abnormal structure and disorganization of extracellular matrix proteins resulting to dysfunction of the leaflets. At its final evolutionary step, treatments are limited to the percutaneous or surgical valve replacement, whatever the original cause of the degeneration. Understanding early molecular mechanisms that regulate valve interstitial cells remodeling and disease progression is challenging and could pave the way for future drugs aiming to prevent and/or reverse the process. Some valve degenerative processes such as the carcinoid heart disease, drug-induced valvulopathy and degenerative mitral valve disease in small-breed dogs are clearly linked to serotonin. The carcinoid heart is typically characterized by a right-sided valve dysfunction, observed in patients with carcinoid tumors developed from serotonin-producing gut enterochromaffin cells. Fenfluramine or ergot derivatives were linked to mitral and aortic valve dysfunction and share in common the pharmacological property of being 5-HT2B receptor agonists. Finally, some small-breed dogs, such as the Cavalier King Charles Spaniel are highly prone to degenerative mitral valve disease with a prevalence of 40% at 4 years-old, 70% at 7 years-old and 100% in 10-year-old animals. This degeneration has been linked to high serum serotonin, 5-HT2B receptor overexpression and SERT downregulation. Through the comprehension of serotonergic mechanisms involved into these specific situations, new therapeutic approaches could be extended to HVD in general. More recently, a serotonin dependent/ receptor independent mechanism has been suggested in congenital mitral valve prolapse through the filamin-A serotonylation. This review summarizes clinical and molecular mechanisms linking the serotonergic system and heart valve disease, opening the way for future pharmacological research in the field.
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14
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Le Tourneau T, Mérot J, Rimbert A, Le Scouarnec S, Probst V, Le Marec H, Levine RA, Schott JJ. Genetics of syndromic and non-syndromic mitral valve prolapse. Heart 2018; 104:978-984. [PMID: 29352010 DOI: 10.1136/heartjnl-2017-312420] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 11/27/2017] [Accepted: 11/27/2017] [Indexed: 11/04/2022] Open
Abstract
Mitral valve prolapse (MVP) is a common condition that affects 2%-3% of the general population. MVP is thought to include syndromic forms such as Marfan syndrome and non-syndromic MVP, which is the most frequent form. Myxomatous degeneration and fibroelastic deficiency (FED) are regarded as two different forms of non-syndromic MVP. While FED is still considered a degenerative disease associated with ageing, frequent familial clustering has been demonstrated for myxomatous MVP. Familial and genetic studies led to the recognition of reduced penetrance and large phenotypic variability, and to the identification of prodromal or atypical forms as a part of the complex spectrum of the disease. Whereas autosomal dominant mode is the common inheritance pattern, an X linked form of non-syndromic MVP was recognised initially, related to Filamin-A gene, encoding for a cytoskeleton protein involved in mechanotransduction. This identification allowed a comprehensive description of a new subtype of MVP with a unique association of leaflet prolapse and paradoxical restricted motion in diastole. In autosomal dominant forms, three loci have been mapped to chromosomes 16p11-p12, 11p15.4 and 13q31-32. Although deciphering the underlying genetic defects is still a work in progress, DCHS1 mutations have been identified (11p15.4) in typical myxomatous disease, highlighting new molecular pathways and pathophysiological mechanisms leading to the development of MVP. Finally, a large international genome-wide association study demonstrated the implication of frequent variants in MVP development and opened new directions for future research. Hence, this review focuses on phenotypic, genetic and pathophysiological aspects of MVP.
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Affiliation(s)
- Thierry Le Tourneau
- l'institut du thorax, INSERM, CNRS, Université de Nantes, Nantes, France.,l'institut du thorax, CHU de Nantes, Nantes, France
| | - Jean Mérot
- l'institut du thorax, INSERM, CNRS, Université de Nantes, Nantes, France
| | - Antoine Rimbert
- l'institut du thorax, INSERM, CNRS, Université de Nantes, Nantes, France
| | | | - Vincent Probst
- l'institut du thorax, INSERM, CNRS, Université de Nantes, Nantes, France.,l'institut du thorax, CHU de Nantes, Nantes, France
| | - Hervé Le Marec
- l'institut du thorax, INSERM, CNRS, Université de Nantes, Nantes, France.,l'institut du thorax, CHU de Nantes, Nantes, France
| | - Robert A Levine
- Cardiac Ultrasound Laboratory, Harvard Medical School, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Jean-Jacques Schott
- l'institut du thorax, INSERM, CNRS, Université de Nantes, Nantes, France.,l'institut du thorax, CHU de Nantes, Nantes, France
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15
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Judge DP, Norris RA. Inheritance Impacts Mitral Valve Insufficiency. ACTA ACUST UNITED AC 2017; 10:CIRCGENETICS.117.001920. [PMID: 28993408 DOI: 10.1161/circgenetics.117.001920] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- Daniel P Judge
- From the Department of Medicine/Cardiology (D.P.J.) and the Department of Regenerative Medicine and Cell Biology (R.A.N.), Medical University of South Carolina, Charleston; and Center for Inherited Heart Disease, Johns Hopkins University, Baltimore, MD (D.P.J.).
| | - Russell A Norris
- From the Department of Medicine/Cardiology (D.P.J.) and the Department of Regenerative Medicine and Cell Biology (R.A.N.), Medical University of South Carolina, Charleston; and Center for Inherited Heart Disease, Johns Hopkins University, Baltimore, MD (D.P.J.)
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