Enzymothérapie substitutive chez un nourrisson atteint de maladie de Pompe : évolution cardiologique

Summary: Pompe disease is an autosomal recessive glycogen storage disorder caused by acid-α-glucosidase deficiency. The infantile form is usually fatal by 1year of age in the absence of specific therapy. We report the cardiac follow-up of a 4-month-old boy treated with enzyme replacement therapy (ERT) for 8months. The patient had no cardiac failure at the age of 1year. Before starting ERT, ECG showed a shortened PR interval, with huge QRS complexes and biventricular hypertrophy; echocardiography demonstrated major hypertrophic cardiomyopathy. The QRS voltage (SV1+RV6) decreased from 13 to 2.9mV after 32weeks of ERT, suggesting a progressive reduction of cardiac hypertrophy and intracellular glycogen excess. The PR interval increased from 60 to 90ms. A block of the right bundle branch appeared after 13weeks of treatment. The indexed left ventricular mass decreased from 240 to 90g/m2 after 30weeks of ERT. The left ventricular ejection fraction decreased transitorily between the 5th and the 15thweeks of treatment. In summary, ERT is an efficient therapeutic approach for the cardiomyopathy of infantile Pompe disease. However, the possible occurrence of a right bundle branch block and a transitory alteration in the ejection fraction highlight the importance of cardiac follow-up. [Copyright &y& Elsevier]