Chordae tendineae rupture complicating the systolic click-late systolic murmur syndrome

In a patient with a documented nonejection systolic click and late systolic murmur, acute mitral insufficiency developed as a result of spontaneous rupture of mitral chordae tendineae. There was no evidence of previous endocarditis, rheumatic fever or congenital heart disease. The ballooning mitral valve syndrome has previously been considered relatively benign. Chordal rupture has been predicted, and presumptive cases have been alluded to by several investigators. This well documented report of such a complication casts further doubt on the benignity of the syndrome.