Normal cardiac contractility in patients with congenital nemaline myopathy.

We made cardiac investigations in 12 patients aged 5-25 years with congenital nemaline myopathy by physical examination, electrocardiography, chest-X-ray and echocardiography to find out whether they showed signs of structural anomalies, specific heart muscle disease, conduction defects or cor pulmonale. One patient had a small ventricular septal defect and one had mitral valve prolapse, neither of which had caused haemodynamic alterations. In the other patients, cardiac findings were normal. Cardiac follow-up seems indicated, however, since cor pulmonale may develop in these patients because of their small vital capacity and restricted breathing movements.