This study describes the echocardiographic characteristics of a family with mitochondrial myopathy, encephalopathy,
lactic acidosis, and stroke-like episodes (MELAS). A 38 year-old man was admitted to this
institution because of progressive heart failure accompanied by a hearing disturbance and diabetes mellitus.
His angiogram showed normal coronary arteries and a deteriorated ejection fraction, and the two-dimensional
echocardiograjn revealed symmetrical hypertrophy of both ventricles with severely reduced
wall motion. Unusually fine sandy refractile myocardial echoes, which reflect the histologic findings of accumulated
abnormal mitochondrias in the cells and interstitial fibrosis, are characteristic in cases of
MELAS. Ultrasonic examination of the patient's mother and younger brother obtained the same refractile
echoes in the thick left ventricular myocardium, although their global systolic function was not impaired.
Point mutation of mitochondrial DNA(3243) was identified in the patient, his mother, and his