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Arrhythmogenic right ventricular dysplasia (ARVD), also called arrhythmogenic right ventricular cardiomyopathy (ARVC) or arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C), is an inherited heart disease. ARVD is caused by genetic defects of the parts of heart muscle (also called ''myocardium'' or ''cardiac muscle'') known as desmosomes, areas on the surface of heart muscle cells which link the cells together. The desmosomes are composed of several proteins, and many of those proteins can have harmful mutations. The disease is a type of nonischemic cardiomyopathy that involves primarily the right ventricle. It is characterized by hypokinetic areas involving the free wall of the right ventricle, with fibrofatty replacement of the right ventricular myocardium, with associated arrhythmias originating in the right ventricle. ARVD can be found in association with diffuse palmoplantar keratoderma, and woolly hair, in a autosomal recessive condition called Naxos disease, because this genetic abnormality can affect also the integrity of the superficial layers of the skin most exposed to pressure stress.〔Freedberg, et al. (2003). ''Fitzpatrick's Dermatology in General Medicine''. (6th ed.). McGraw-Hill. ISBN 0-07-138076-0.〕〔James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. ISBN 0-7216-2921-0.〕 ARVC/D is an important cause of ventricular arrhythmias in children and young adults. It is seen predominantly in males, and 30-50% of cases have a familial distribution. ==Genetics== It is usually inherited in an autosomal dominant pattern, with variable expression. Only 30% to 50% of individuals affected by ARVC will test positive to one of the known genetic mutations in chromosomal loci associated with the disease.〔Cox MGPJ, van der Zwaag PA, van der Werf C, et al. Arrhythmogenic right ventricular dysplasia/cardiomyopathy. Circulation 2011; 123:2690 –700. 3.〕〔Fressart V, Guthoit G, Donal E, et al. Desmosomal gene analysis in arrhythmogenic right ventricular dysplasia/cardiomyopathy: spectrum of mutations and clinical impact in practice. Europace 2010;12:861– 8.〕 Novel studies showed that mutations (point mutations) in genes encoding for desmosomal proteins (see intercalated disc) are the main causatives for the development of this disease. Recently it has been shown, that mutations in the desmin DES gene could cause ARVC. Desmin is an intermediate filament protein, which is linked to the desmosomes. Different ''DES'' muations cause an abnormal aggregation of desmin and associated proteins. The penetrance is 20–35% in general, but significantly higher in Italy. Seven gene loci have been implicated in ARVD. It is unclear whether the pathogenesis varies with the different loci involved. Standard genetic screening test are currently tested and evaluated in different state of the art cardiovascular research centres and hospitals. Types include: 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「arrhythmogenic right ventricular dysplasia」の詳細全文を読む スポンサード リンク
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