Double-chambered left ventricle - from clinical to basic

Title : Double-chambered left ventricle - from clinical to basic

Abstract:

Introduction: Double-chambered left ventricle (DCLV) is a particularly rare congenital cardiovascular malformation that is difficult to diagnose. It is characterized by the subdivision of the left ventricle into two chambers by an abnormal septum or muscle band. Compared to double-chambered right ventricle (DCRV), DCLV is an extremely rare anomaly with few cases having been previously reported.

Material and Methods: From January 2012 to November 2023, 12 patients, including five males and seven females, ranging from 2 to 41 years, were diagnosed with DCLV using echocardiography in our hospital. The clinical manifestations included cyanosis, cough, fatigue, palpitations, and dyspnea. Physical examination revealed tachypnea, decreased breath sounds, and wheezing. Cardiac examination revealed enlarged heart borders, decreased heart sounds, and grade 3/6 systolic ejection murmurs in the left 3-4th intercostal space.

Results: All patients underwent chest radiography, electrocardiogram, and echocardiography; nine patients underwent cardiac magnetic resonance imaging (CMRI). Among the patients in this group, one died of multiple organ failure 1 year after the diagnosis. The remainder was followed up at our hospital. Familial aggregation was observed in these cases. Five individuals in the family were diagnosed with DCLV. We discovered a novel rare variant of MYH7, the causative gene for several heart diseases, in the patients from this family.

Conclusions: DCLV is a rare cardiac disease in which the LV is divided into two chambers. Echocardiography plays an important role in the diagnosis of DCLV and in differentiating it from other diseases. This is the first report of familial DCLV and identification of MYH7 as its genetic cause. Additionally, our results provide useful information of MYH7-associated diseases.

Keywords: Double-chambered left ventricle, Echocardiography, Diagnosis, Genetics.

Biography:

Dr. Wang studied Pediatrics at the Capital Medical University, Beijng, China and graduated in 1989. She then joined Heart Center, Beijing Children's Hospital, Capital Medical University, National Center for Children's Health. She received her MD degree in 2008 at the same university. She has been to New York-Presbyterian Morgan Stanley Children’s Hospital, Columbia University Medical Center as a visiting scholar. She had ten years of pediatric cardiac clinical experience. And as a major professional area, she has done echocardiography for twenty-five years. She had published more than 30 articles on the professional journal of China and SCI.