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Chest pain during exercise as first manifestation of Friedreich's ataxia.

Cardiac function is affected in up to 90% of patients with Friedreich's ataxia, the most common spinocerebellar degenerative disease. Friedreich's ataxia typically causes motor abnormalities of the extremities, mainly impairing walking and the coordination of the legs and arms. The myocardium is affected at a later stage of the disease. The extent and timing of myocardial involvement determines the clinical course. Some patients have no cardiac symptoms and cardiac involvement can be established only by electrocardiographic or echocardiographic examination. In addition some pathological studies have found evidence of coronary abnormalities, mainly in the small vessels. There are no reports that such lesions cause angina. In a 16 year old patient chest pain on exercise had been the presenting symptom of Friedreich's ataxia at the age of 9. Considerable alterations in ventricular repolarisation on the electrocardiogram suggested a congenital coronary abnormality or hypertrophic myocardiopathy. The results of a Doppler echocardiography, Holter monitoring, and a haemodynamic study with coronary arteriography were all normal. An exercise test when the boy was 13 indicated significant changes in ventricular repolarisation. Myocardial scintigraphy (99mTc-MIBI) at that time, however, was normal. He improved slightly when he was treated with verapamil. When he was 15 neurological symptoms developed and Friedreich's ataxia was diagnosed. Typical angina during exercise seems to have been the first symptom of Friedreich's ataxia.