Amaurosis fugax caused by a prolapsed mitral valve leaflet in the midsystolic click, late systolic murmur syndrome.

A 28-year-old man had recurrent episodes of amaurosis fugax of eight years' duration and had a congenital, late systolic mitral insufficiency murmur with the characteristics of the midsystolic click, late systolic murmur syndrome. The ophthalmologist must consider the clinical entity of the midsystolic click, late systolic murmur syndrome in the differential diagnosis of amaurosis fugax, especially when such attacks occur in young patients.