A form of congenital heart disease in which one or both leaflets of the mitral valve protrude into the left atrium during the systolic phase of ventricular contraction. It may be associated with valve infection, arrhythmias and atypical chest pain. Some cases are asymptomatic, but a pronounced midsystolic click with or without late systolic murmur, usually indicates the presence of this disorder. Women about twice as often affected as men. The syndrome may occur as a complication of various conditions. Aetiology unknown; familial courses have been described; autosomal dominant inheritance possible.
Barlow was the first to interpret this auscultation syndrome, known for decades, as an expression of a mitral valve prolapse. Inheritance is autosomal dominant.
- J. B. Barlow, P. Marchand, W. A. Pocock, D. Denny:
The significance of late systolic murmurs.
American Heart Journal, St. Louis, 1963, 66: 443.
- J. B. Barlow, C. K. Bosman, J. W. C. Cochrane:
Congenital cardiac arrhythmia. Lancet, London, 1964, II: 531.