Discovery of a new mutation in the desmin gene in a young patient with cardiomyopathy and muscular weakness.

A 25-year-old woman with a five years history of syncope, mild left ventricular hypertrophy and moderately enlarged atria, was diagnosed with third degree atrioventricular heart block alternating with atrioventricular heart block 2:1, and received a dual chamber pacemaker. After three years of evolution, she developed atrial fibrillation, marked biatrial enlargement, severely depressed longitudinal myocardial velocities, associated with mild girdle weakness and slight increase in creatine kinase level. The diagnosis of restrictive cardiomyopathy with mild skeletal myopathy imposed the screening for a common etiology.