Mitral valve prolapse, aortic compliance, and skin collagen in joint hypermobility syndrome.

Abstract

SUMMARY Mitral valve prolapse was sought clinically and with phonocardiography and M mode and sector echocardiography in 15 women aged 22-57 years with joint hypermobility syndrome. The type III:III + I collagen ratio was measured in skin biopsy specimens and was found to be raised in seven of 10 patients sampled. Thirteen patients had increased aortic wall compliance measured by the continuous wave Doppler ultrasound technique. Ten (67%) patients had mitral valve prolapse shown by auscultatory signs or echocardiography or both-a prevalence at least three times greater than that in the general adult population.It is concluded that if the abnormality of collagen biosynthesis found in skin biopsy samples in these patients is also present in their mitral valve tissue this may predispose them to prolapse of the valve.The primary mitral valve prolapse syndrome is one of the commonest cardiac abnormalities, being present in 4-21% of the adult population.' 2 Most of those affected are symptom free and have a good prognosis,3 but sudden death,45 infective endocarditis,6 spontaneous chordal rupture, and progressive mitral regurgitation7 are rare complications and make this an important condition to recognise. The subject has been well reviewed.28-12The synonymous term, floppy mitral valve syndrome, emphasises the well established structural abnormality of the valve leaflets, although the molecular basis for this defect remains unclear. The main structural abnormality of the valve leaflets in primary mitral valve prolapse consists of myxomatous degeneration and disruption of the pars fibrosa and there is dilatation of the mitral annulus.2The association of mitral valve prolapse with certain inherited diseases (secondary mitral valve prolapse) including the Marfan syndrome,'3 the Ehlers-Danlos syndrome,'4 and osteogenesis imperfecta,'5 lends support to the hypothesis that mitral valve prolapse may be due to abnormalities in the Requests for reprints to Dr Clive E Handler, Department of Cardiology, Guy's Hospital, London SEI 9RT.Accepted for publication 22 July 1985 production or structure of collagen. Such changes have been shown to occur in these conditions.'6The hypermobility syndrome is a sex influenced usually dominantly inherited disorder of collagen production characterised by non-inflammatory joint pain associated with generalised joint laxity.17Mitral valve prolapse is present in about a third of cases,' 819 providing further evidence that a systemic abnormality of collagen may be associated with mitral valve prolapse. There is, at present, little information on this connection. One study of the family of a patient with type IV Ehlers-Danlos syndrome has shown a consistent association of mitral valve prolapse and abnormally low type III collagen production.20 A more recent study, however, has shown an increased proportion of type III collagen in floppy mitral valve tissue compared with normal controls.21The purpose of this study, therefore, was to assess the frequency of mitral valve prolapse among a group of patie...

The Relationship Between Echocardiographic Features of Mitral Valve and Elastic Properties of Aortic Wall and Beighton Hypermobility Score in Patients With Mitral Valve Prolapse

“…[1][2][3] MVP is three-times more prevalent in patients with BJHMS than other patients and may be present in up to one third of all individuals with BJHMS. [7][8][9]29) However, there are a few reports with conflicting results on the incidence of BJHMS in MVP 15,16) and the relation between the echocardiographic features of mitral valves and elastic properties of the aortic wall and BHS in patients with both MVP and BJHMS. 7,15) In this study, we investigated the incidence of BJHMS in patients with MVP and whether BHS in MVP patients is related to the echocardiographic features of mitral valve prolapse and elastic properties of the aortic wall.…”

“…14) However, there have been a few studies on the relation between the echocardiographic features of mitral valves [anterior mitral leaflet thickness (AMLT), 15) maximal leaflet displacement (MLD), 7) degree of mitral regurgitation (DMR)], elastic properties of the aortic wall [index of aortic systolic (AOSDI) and diastolic diameters (AODDI), index of aortic stiffness (IAOS) and aortic distensibility (AOD)], and Beighton hypermobility score (BHS) in MVP patients with BJHMS. 9) In addition, previous studies have given conflicting results with respect to the incidence of BJHMS in MVP. 15,16) The present study was designed to investigate the incidence of BJHMS in MVP and determine whether there was a correlation between the echocardiographic features of the mitral valve and elastic properties of the aortic wall and BHS in patients with MVP and BJHMS.…”

“…6) In the following years, a high incidence of MVP has been reported in patients with benign joint hypermobility syndrome (BJHMS), 7,8) which, like MVP, is inherited mainly as a sex-influenced dominant trait. 9,10) Abnormalities of collagen have been found in myxomatous or floppy valves of patients with MVP [11][12][13] that coincide with those identified in skin biopsies of patients with hypermobility syndrome 9) leading to the suggestion of a common pathogenetic mechanism of abnormal production or maturation of collagen. 14) However, there have been a few studies on the relation between the echocardiographic features of mitral valves [anterior mitral leaflet thickness (AMLT), 15) maximal leaflet displacement (MLD), 7) degree of mitral regurgitation (DMR)], elastic properties of the aortic wall [index of aortic systolic (AOSDI) and diastolic diameters (AODDI), index of aortic stiffness (IAOS) and aortic distensibility (AOD)], and Beighton hypermobility score (BHS) in MVP patients with BJHMS.…”

“…33) In another study, the concordance between inadequate production of type III collagen and echocardiographic findings of MVP in patients with type IV Ehler-Danlos syndrome have suggested that this collagen abnormality may be the responsible factor in patients with this syndrome. 34) Abnormalities of collagen have been found in myxomatous or floppy valves of patients with MVP [11][12][13] that coincide with those identified in skin biopsies of patients with hypermobility syndrome 9) leading to the suggestion of a common pathogenetic mechanism of abnormal production or maturation of collagen. 14) Several clinical observations have led to the speculation that primary MVP syndrome represents a generalized disorder of connective tissue.…”

“…32) In patients with BJHMS, the ratio of type III collagen to type III + type I collagen is increased. 9,14) The abnormal ratio of type III collagen to type I collagen is thought to cause the decreased tissue stiffness seen in patients with BJHMS. Decreased stiffness of joint structures produces the joint hypermobility most obvious in patients with BJHMS; decreased stiffness of other tissues may result in the prolapse seen in other organs.…”