Isolated noncompaction of the left ventricular myocardium in an elderly patient.

Noncompaction of the ventricular myocardium (NVM) is a rare disorder of endomyocardial morphogenesis characterized by numerous, prominent trabeculations and deep intertrabecular recesses. It is commonly associated with congenital heart disease, but the isolated form (INVM) is not associated with other structural heart diseases. Clinical reports of INVM have been limited to a few case reports and small series of pediatric patients. INVM is considered to be a form of congenital abnormal endomyocardial morphogenesis caused by abnormal cessation of the embryonic development of the ventricular myocardium; most reported cases have been pediatric patients, and autopsy cases of elderly patients have been quite rare. In the present case, an elderly female had INVM associated with severely disturbed left ventricular (LV) function and an enlarged left ventricle similar to dilated cardiomyopathy. The echocardiogram showed prominent trabeculations and deep intertrabecular recesses of the LV walls, especially in the posterior and apical areas. LV contrast echocardiography revealed markedly protruberant trabeculations, which were also observed with computed tomography. Five years later, the patient died of refractory heart failure and ventricular fibrillation. The autopsy revealed numerous excessively prominent trabeculations in the LV myocardium, with deep intertrabecular recesses containing thrombi.