Complete atrioventricular block as the first manifestation of noncompaction of the ventricular myocardium.

Noncompaction of ventricular myocardium (NVM) is a rare cardiomyopathy, most probably caused by disturbances in embryonic morphogenesis of the myocytes, resulting in prominent trabeculations in the ventricular myocardium. Several diagnostic criteria have been proposed by echocardiography, and its association with other heart diseases is common. Its mortality is closely related to ventricular dysfunction, cardiac arrhythmias, and cardioembolic events.