Noninvasive evaluation of cardiac involvements and left ventricular function in schoolchildren with the history of mucocutaneous lymph node syndrome

Mucocutaneous lymph node syndrome (MCLS) in the young has been known to have coronary aneurysms, and then it has been recently suspected as a cause of premature atherosclerosis and cardiomyopathy. Thirty-three schoolchildren who suffered from MCLS were studied to evaluate cardiac involvements and left ventricular function using two-dimensional (2-D) echocardiograms and submaximal stress test. Fifteen normal schoolchildren were studied as normal control. All these MCLS children were asymptomatic and had no significant findings in routine chest X-ray and electrocardiographic examinations. According to submaximal stress test, 8 cases showed a J type ST depression of only 0.5--1.0 mm, and there were no positive cases. Using 2-D echocardiograms, the left coronary artery was detected in 85% and the right coronary in 27%. One case showed an aneurysm of the left coronary artery. However, none of them showed abnormal left ventricular wall motion or the wall motion abnormality compatible with cardiomyopathy. There were no significant differences between MCLS and normal control in ejection fraction, mean VCF, diastolic descent rate of the anterior mitral valve, D/S ratio of the left ventricular wall, and Weissler's index (PEP/ET). These findings suggested that 1) most of MCLS schoolchildren do not have obvious cardiac involvement and their left ventricular function is within normal limits, 2) because of its low sensitivity, submaximal stress test is not so useful in screening coronary lesions, and 3) the 2-D echocardiogram works not only in detecting coronary aneurysms but also in evaluating left ventricular function.