Left Ventricular Noncompaction

Abstract

Left ventricular noncompaction (LVNC) cardiomyopathy is a heterogeneous condition that is gaining recognition as a distinct clinical entity. It is characterized by numerous, excessively prominent ventricular trabeculations with deep trabecular recesses and the formation of 2 distinct layers of myocardium. It is often unrecognized clinically for decades and poses distinct life-threatening complications. Accurate diagnosis is key to minimizing risks associated with LVNC. This article will introduce clinicians to the defining criteria and diagnostic process for recognition of LVNC. Left ventricular noncompaction is an important clinical entity not easily recognized at first glance but has important clinical ramifications for treatment requiring an accurate diagnosis. Left ventricular noncompaction is present at birth but can remain clinically silent for decades. It is found both in isolation and as a part of other congenital cardiac, extracardiac, neuromuscular, and genetic syndromes. Left ventricular noncompaction is associated with the major complications of heart failure, tachyarrhythmias, and systemic thromboembolism. Transthoracic echocardiography will likely remain the initial screening modality, but modality limitations, questionable findings, and clinical presentations suspicious for noncompaction should be followed up promptly with cardiac magnetic resonance imaging for definitive diagnosis and treatment.