Cardiac involvement in glycogen storage disease type III.

Twenty patients with enzymatically proven glycogen storage disease type III (GSD III) aged 3-30 years underwent cardiological evaluation. Seventeen showed subclinical evidence of cardiac involvement in form of ventricular hypertrophy on ECG. Of 16 patients in whom an ECG examination was performed, 13 had abnormal echocardiographic features. Only 2 patients had cardiomegaly on X-ray. The cardiac findings in 1 of the patients, a 25-year-old female with clinically evident cardiomyopathy are described in detail. In view of our findings, patients with established GSD III, should not only be investigated regarding their muscular involvement, but should also undergo a detailed evaluation of their cardiac status.