Ruptured mitral chordae tendineae.

AMONG THE LESIONS responsible for insufficiency of the mitral valve is rupture of the chordae tendineae. It is our purpose to describe the significant clinical and pathologic findings in 20 cases of insufficiency of the mitral valve due to rupture of the chordae tendineae. This report is based on those cases in which ruptured mitral chordae tendineae were found at necropsy at the Mayo Clinic during the years 1934 to 1958 inclusive. The important etiologic factors claimed for rupture of the mitral chordae tendineae are bacterial endocarditis,15 rheumatic valvular disease,6 7 and trauma.8 9 Cases have been encountered, however, in which conclusive evidence of these conditions has not been demonstrated. In those cases in which evidence for a specific etiologic factor is lacking, so-called spontaneous rupture10' 11 must be considered. Though myocardial infarction is the prominent cause of mitral insufficiency due to ruptured papillary muscles,12' 13 it has not been demonstrated to be of importance in rupture of the chordae tendineae.