Truncus arteriosus (TA) is a rare congenital cardiovascular anomaly characterized by a single arterial trunk arising from the heart by means of a single semilunar valve (<I>i.e.</I> truncal valve). Pulmonary arteries originate from the common arterial trunk distal to the coronary arteries and proximal to the first brachiocephalic branch of the aortic arch. TA typically overrides a large outlet ventricular septal defect (VSD). The intracardiac anatomy usually displays situs solitus and atrioventricular (AV) concordance.
In left atrial isomerism there is a bilateral small finger-shaped morphologically left atrial appendage joining the atrial chamber along a narrow front without an internal terminal crest.
Prenatal diagnosis of 22q11 deletions: a series of five cases with congenital heart defects.
Raymond FL, Simpson JM, Mackie CM, Sharland GK. J Med Genet. 1997;34(8):679-82.
The cardiac abnormalities included tetralogy of Fallot with absent pulmonary valve, pulmonary atresia with VSD, common arterial trunk, and left atrial isomerism with double outlet right ventricle.
