Acute mitral regurgitation in pregnancy due to ruptured chordae tendineae.

Rupture of chordae tendineae resulting in acute mitral regurgitation has previously been described following rheumatic fever, subacute bacterial endocarditis, blunt chest trauma, and in Marfan's syndrome. Chordae may rupture spontaneously in older patients, producing a characteristic clinical syndrome, but such 'idiopathic' rupture is exceptional before the age of 50. This paper reports the occurrence of acute mitral regurgitation due to spontaneous rupture of the chordae tendineae in a previously healthy 19-year-old girl during her second pregnancy. A similar case has not previously been described. Since the clinical and haemodynamicfindings were very similar to those seen in older patients, the correct diagnosis was made preoperatively. At operation, rupture of the chordae to the posterior leaflet was found and the valve was replaced by a frame-mounted aortic homograft. Two months later this became detached from the annulus posteriorly and was successfully resutured at a second operation.