Mitral valve prolapse in five members of a family including the identical twins.
A family in which the five members including the identical twins had a mitral valve prolapse was described. None of these members had any known stigmata of Marfan syndrome and their auscultatory findings were different each other. M-mode echocardiograms disclosed a midsystolic buckling of the mitral valve in the identical twins, their parents and the mother's brother, but all were asymptomatic. Electrocardiograms revealed a wandering pacemaker in two members. The index case was a 13-year-old girl whose apical late systolic murmur was detected incidentally by the mass screening examination for cardiac diseases. Both the inhalation of amyl nitrite and injection of methoxamine induced the augmentation of this murmur and made it holosystolic. The identical twin of the index case had multiple apical non-ejection clicks. However, a mitral regurgitant murmur was not induced by pharmacological provocations. Two-dimensional echocardiograms revealed prolapse of both the anterior and posterior mitral valve leaflets in both of them. Their mother had a late systolic click and the mother's brother had a cardiopulmonary murmur. The abnormal auscultatory findings were not observed in their father. This familial study suggested the genetic background and the various clinical manifestations of mitral valve prolapse.
D000293:Adolescent; D000328:Adult; D000368:Aged; D004200:Diseases in Twins; D005260:Female; D006680:HLA Antigens / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D008945:Mitral Valve Prolapse / Q000175:diagnosis / Q000235:genetics* / Q000276:immunology
D006680:HLA Antigens