[Cardiologic aspects of Friedreich type heredoataxia]. / Aspects cardiologiques de l'hérédoataxie du type Friedreich.

ABSTRACT

The authors performed ambulatory electro-vectorcardiography polycardiography and echocardiography in 18 patients with typical Friedreich's disease, and 6 patients with atypical forms of hereditary spino-cerebellar ataxia classified on e basis of the degree of neurological involvement, without clinical signs of cardiocirculatory failure. The ECG and VCG recording commonly showed appearances suggestive of myocardial "necrosis" and were of little value in the differential diagnosis between typical and atypical forms of Friedreich's ataxia. This limitation also applied to the kinetocardiogramme which was sometimes pathological confirming the echocardiographic diagnosis of symmetric LV hypertrophy and of septal hypokinesia despite normal ECG and VCG. The systolic time intervals and echocardiographic parameters of the interventricular septum were more helpful in the differential diagnosis. Hypertrophic cardiomyopathy, usually symmetric, was observed in about 70 p. 100 of typical and only rarely in atypical forms of Friedreich's disease. The symmetric or asymmetric hypertrophy was associated with reduced left ventricular performance in less than 20 p. 100 of typical Friedreich's disease, systolic anterior motion of the mitral valve and other signs of dynamic left ventricular outflow tract obstruction were not observed in any of these patients. The correlations between the degree of neurological disability and the cardiac abnormalities, were, in general, disappointing compared with other reported series. The cardiac investigation of patients with Friedreich's disease remains valuable from the point of view of recent pathological hypotheses of a metabolic abnormality with eventual therapeutic implications.