Cardiac Aspects of Friedreich's Ataxia

Twenty-seven kindreds with Friedreich's ataxia were seen at the Johns Hopkins Hospital from 1935 to 1957. In three kindreds the disease exhibited an apparently dominant mode of inheritance. Affected individuals in each of the remaining 24 kindreds were confined to single sibships and in 18 of these limited to a single patient. Thirty-three patients from these kindreds were studied in considerable detail. Follow-up information was obtained on all individuals and electrocardiograms together with chest x-rays were obtained on most of them. Eighteen or 55 per cent exhibited major cardiac abnormalities including cardiac enlargement in four and possible enlargement in an additional two, prominent systolic murmurs in six, a diastolic murmur and other signs suggesting mitral stenosis in one, probable pericardial effusion in another, and major electrocardiographic abnormalities in 16. Two developed atrial fibrillation and one atrial flutter. Heart disease contributed to death definitely in four and possibly in two others of eight patients who have died. Autopsy was performed in two patients; diffuse myocardial fibrosis was found in one of these. An unusual feature of the cardiac disturbance in five patients was the tendency of remission toward normalcy. This finding, together with the supposition that some patients were seen before developing evidence of heart disease, indicates that the frequency of cardiac abnormality probably exceeds the minimum estimate of 55 per cent. In eight patients Friedreich's ataxia with cardiac involvement was mistaken for rheumatic or congenital heart disease. The appearance of leg pains early in the disease increased the mimicry of rheumatic fever in a number of patients. Both cardiac and neurologic manifestations of Friedreich's ataxia are regarded as having a common genetic origin and serve as another example of pleiotropy.