Left Ventricular Noncompaction: New Insights into a Poorly Understood Disease

Abstract

Left ventricular noncompaction (LVNC) is a congenital pathology that directly affects the lining walls of myocardial tissue, causing trabeculations with blood filling in the inner wall of the heart, concomitantly with the development of a mesocardial thinning. Although LVNC was described for the first time as long ago as 1984, our understanding of the disease with regard to its genetic pattern, diagnosis, clinical presentation and treatment is still scanty. LVNC can present as an isolated condition or associated with congenital heart disease, genetic syndromes or neuromuscular disease. This suggests that LVNC is not a distinct form of cardiomyopathy, but rather a morphological expression of different diseases. Recognition of the disease is of fundamental importance because its clinical manifestations are variable, ranging from the absence of any symptom to congestive heart failure, lethal arrhythmias and thromboembolic events. The study of this disease has emphasized its genetic aspects, as it may be of sporadic origin or hereditary, in which case it most commonly has an autosomal dominant inheritance or one linked to the X chromosome. Echocardiography is the gold standard for diagnosis, and magnetic resonance imaging may refine the identification of the disease, especially in those patients with non-conclusive echocardiography. This article sets out to review the main characteristics of LVNC and present updates, especially in the genetic pattern, diagnosis and treatment of the disease.

Keywords: Compacted myocardium; genetic heart diseases; left ventricular; myocardial trabeculations; noncompaction; rare heart diseases..

Fig. (1)

Echocardiographic 4-chamber image from a patient with LVNC. The color Doppler highlights perfusion of intertrabecular recesses from the left ventricle. RV: right ventricle; LV: left ventricle; RA: right atrium; LA: left atrium. Courtesy of Paulo G.Menge M.D. (A higher resolution / colour version of this figure is available in the electronic copy of the article).