Left Ventricular Noncompaction in Children Carline Koh, MBBS, Pui-Wah Lee, MBBS, Tak-Cheung Yung, MBBS, Kin-Shing Lun, MBBS, and Yiu-Fai Cheung, MD Department of Paediatrics and Adolescent Medicine, Division of Paediatric Cardiology, Grantham Hospital, The University of Hong Kong, Hong Kong, China ABSTRACT Objective. Left ventricular noncompaction (LVNC) is an uncommon type of cardiomyopathy in children. We sought to determine the clinical presentations and outcomes of children diagnosed to have LVNC. Design. The case records of children diagnosed to have LVNC between 1999 and 2007 were reviewed. The diagnosis was based on echocardiographic finding of a thick noncompacted myocardium layer characterized by a trabecular meshwork with deep endomyocardial spaces. Results. Ten patients (seven males) were diagnosed to have LVNC at a median age of 2 years (range, 7 days to 12 years). Seven patients had isolated LVNC while three had associated structural congenital heart diseases. The right ventricle was also involved in two patients. Clinical presentations included congestive heart failure in eight patients, asymptomatic heart murmur in one, and syncope with exercise intolerance in one. At presentation, cardiomegaly was found in nine patients, electrocardiographic abnormalities in nine, and impaired LV contraction in six. Eight patients received anti-heart failure medications. Three patients died at a median of 1.5 years after diagnosis, two died suddenly of unknown causes, and one of heart failure. The seven surviving patients were followed up for a median of 2 years (range, 2 months to 3 years). Three patients developed cardiac arrhythmias. The LV function improved in three patients and worsened in one on follow-up. None of the patients developed thromboembolic complications. Conclusions. Left ventricular noncompaction in children is a heterogeneous condition. Long-term follow-up for development of progressive LV dysfunction and cardiac arrhythmias is indicated. Key Words. Ventricle; Cardiomyopathy; Noncompaction; Heart Failure Introduction D uring early embryonic development, the human myocardium consists of a meshwork of interwoven myocardial fibers that form trabe- culae with deep intertrabecular recesses. 1 At 5–8 weeks of gestation, the ventricular myocardium gradually compacts itself with transformation of intertrabecular spaces to capillaries and regression of spaces between trabeculae. 1 An arrest of this normal process of myocardial compaction is believed to result in left ventricular noncompac- tion (LVNC), categorized previously as a type of unclassified cardiomyopathy by the World Health Organization. 2 Recently, this condition has been classified under the category of genetic cause of primary cardiomyopathy by the American Heart Association. 3 In the past decade, increased aware- ness of this entity has led to its increasing diagnosis in the pediatric population, 4,5 although data remain limited. The present study aimed to review a single-center experience in the diagnosis and management of children with LNVC over a 9-year period. Methods The clinical records of 10 consecutive infants and children diagnosed to have LVNC between January 1999 and December 2007 in our institu- tion, the major pediatric tertiary cardiac center in Hong Kong, were reviewed. Diagnosis of LVNC was based on two-dimensional echocardiographic findings of a two-layered myocardial structure that consisted of a compacted thin epicardial layer and a thicker noncompacted endocardial layer, with maximum end-systolic ratio of noncompacted to compacted layer >2. The noncompacted layer was characterized by presence of trabecular meshwork with deep intertrabecular recesses communicating with the ventricular cavity (Figure 1). 6 288 © 2009 Copyright the Authors Journal Compilation © 2009 Wiley Periodicals, Inc. Congenit Heart Dis. 2009;4:288–294