Cardiac manifestations of neuromuscular disorders in children.

Cardiac abnormalities occur in association with many of the neuromuscular disorders that present in childhood. Genetic defects involving the cytoskeleton, nuclear membrane, and mitochondrial function have all been described in patients with skeletal myopathy and cardiac involvement. The most common classes of neuromuscular disorders with cardiac manifestations are the muscular dystrophies- Duchenne, Becker, limb-girdle and Emery Dreifuss. Friedreich Ataxia and myotonic dystrophy also have important cardiac involvement. The type and extent of cardiac manifestations are specific to the type of neuromuscular disorder. The most common cardiac findings include dilated or hypertrophic cardiomyopathy, atrioventricular conduction defects, atrial fibrillation and ventricular arrhythmias. Screening for cardiac involvement should be performed in all children with neuromuscular disorders that have the potential for cardiac involvement. This review discusses the cardiac findings associated with specific neuromuscular disorders and outlines the indications for evaluation and treatment.