Severe mitral regurgitation due to coronary arteritis of mucocutaneous lymph node syndrome. A new surgical entity.

Case histories are reported of three patients, 1 to 4 years of age, with severe mitral regurgitation that occurred as a sequela of mucocutaneous lymph node syndrome (MCLS). These patients were found among 12 patients with coronary artery lesions such as aneurysms, narrowings, and obstructions. One of them with multiple coronary aneurysms and also severely impaired left ventricular function died of congestive heart failure in the 2 years and 7 months' follow-up period after the acute illness. The second patient, 1 year of age, had multiple coronary aneurysms and mitral regurgitation. Because of the difficulty in treating coronary artery lesions at this patient's age and also because of medically controllable mitral regurgitation at present, this patient is now under careful observation. The third patient, whose condition was complicated by inferior wall myocardial infarction due to occlusion of the right coronary artery, underwent mitral valve replacement for intractable heart failure and cardiac cachexia. This patient had slow but definite improvement postoperatively. Mitral regurgitation secondary to MCLS usually is complicated by the associated difficult coronary artery lesions and impaired left ventricular function. Although this fact causes an extra-difficult situation, mitral regurgitation consequent to MCLS is amenable to surgical treatment and this disease should now be considered as a new surgical entity.