[Mitral regurgitation due to ruptured chordae tendineae in the aged: a clinicopathologic study].

We observed 13 cases of mitral regurgitation (MR) due to ruptured chordae tendineae (RCT) among 4,000 consecutive autopsies of patients over 60 years of age (0.33%). There were four men and nine women whose average age was 79.8 yrs. Five cases had a single RCT (Group I) and eight had multiple RCT (from two to eight chordae) (Group II). The sites of RCT were in the posterior mitral leaflet (PML) in nine, the anterior leaflet in one, and both in three. All in Group I showed RCT in the PML; the posterior scallop in two and the middle scallop in three. The average heart weight was 340 g in Group I and 431 g in Group II. Sclerosis of the coronary arteries, the circumference of the mitral valve ring, and thickness of the leaflets did not differ significantly. Estimated volume of the left atrium was significantly greater in Group II than in Group I (185 ml vs 57 ml, p less than 0.05). Jet lesions were observed in 10 of the 13 cases. The etiologies of RCT were previous endocarditis in two, mitral valve prolapse in three, and spontaneous rupture in eight. Congestive heart failure was observed in three (60%) in Group I and eight (100%) in Group II (p less than 0.01). Cardiothoracic ratio more than 60% was observed in three (60%) of Group I and six (75%) of Group II. Atrial fibrillation was demonstrated in one in Group I (20%) and six (75%) in Group II (p less than 0.05), and cardiac death in one (20%) in Group I and six (75%) in Group II (p less than 0.05). Phonocardiograms showed pansystolic murmur in all cases, third heart sound in nine (69%), and fourth heart sound in four (57%). Echocardiographically, RCT was diagnosed in six of nine cases (67%). In conclusion, patients with RCT involving more than two chordae tendineae can show more severe clinical course than cases with a single RCT.