A neonate is found to have a cyanotic congenital heart disease with a single common arterial trunk arising from both ventricles. Failure of partitioning of which embryological structure causes this defect?

• A Sinus venosus
• B Bulbus cordis
• C Septum primum
• D Truncus arteriosus ✓

Explanation

Persistent truncus arteriosus results from failure of the aorticopulmonary septum (which normally partitions the truncus arteriosus) to form. The aorticopulmonary septum is derived from neural crest cells and divides the truncus into the ascending aorta and pulmonary trunk. Deficient neural crest cell migration (as in DiGeorge syndrome) underlies many conotruncal heart defects including truncus arteriosus and tetralogy of Fallot.

Reference: BD Chaurasia's Human Anatomy, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.