Guiding the management of ventricular arrhythmias in patients with left ventricular noncompaction cardiomyopathy: a knowledge gap.

Left ventricular noncompaction (LVNC) is a cardiomyopathy that occurs due to an arrest of myocardial maturation during embryogenesis. The diagnostic echocardiographic features in individuals with LVNC include a thick, bilayered myocardium, prominent ventricular trabeculations, and deep intertrabecular recesses. Clinical features associated with LVNC vary in asymptomatic and symptomatic patients, and include the potential for heart failure, conduction defects (eg, left bundle branch block), supraventricular and ventricular arrhythmias, thromboembolic events, and sudden cardiac death. The authors report five cases that emphasize asymptomatic and apparently benign symptoms in patients with LVNC; despite normal physical examination and 12-lead electrocardiogram results, all of these cases unveiled potentially serious clinical consequences. These cases highlight the concern that LVNC patients with mild to moderate left ventricular systolic dysfunction, particularly in the presence of ventricular arrhythmias or a family history of sudden cardiac death, may need consideration for an implantable cardioverter defibrillator (ICD). All potential benefits of an ICD need to be balanced by the risk of device infection, lead and device malfunction, and potential for inappropriate shocks.