Evidence of left ventricular dysfunction in children with merosin-deficient congenital muscular dystrophy

Background Deficiency of the sarcolemmal protein dystrophin has been linked to dilated cardiomyopathy. Some children with congenital muscular dystrophy have a deficiency of the laminin α 2 chain of merosin, an extracellular matrix protein linked to dystrophin through a group of glycoproteins. It has been shown that deficiency in one of these glycoproteins is responsible for muscular dystrophy and dilated cardiomyopathy. Children with laminin α 2 deficiency may be at risk for development of cardiomyopathy. Methods and Results We studied the cardiac function of a cohort of 16 children with congenital muscular dystrophy by using 2-dimensional echocardiography. The expression of the laminin α 2 of merosin in the patients was determined on a skin or muscle biopsy. Two of 6 merosin-deficient children had an ejection fraction