The varying evolution of Friedreich's ataxia cardiomyopathy.

During a mean follow-up period of 8 years, 17% of 66 patients with Friedreich's ataxia developed hypokinetic-dilated cardiomyopathy; most patients originally had a hypertrophic left ventricle. The presence of pathologic Q waves identifies a subgroup of patients with wall motion abnormalities; these patients are more likely to develop a hypokinetic left ventricle, and the prognosis is ostensibly poorer.