Common Arterial Trunk

Abstract

Truncus arteriosus communis (TAC) is a rare type of congenital heart disease. Secondary to incomplete septation of the great vessels, there is only one great vessel known as the common arterial trunk leaving the heart. The takeoff of the confluent or separate pulmonary arteries from the truncus arteriosus is variable and prompted different anatomical classification systems (Van Praagh, Collett and Edwards). The truncal valve, which can appear as a fusion of aortic and pulmonary valve, has up to six leaflets, although three to four leaflets are most commonly found. The leaflets are sometimes deficient and very dysplastic leading to severe truncal valve regurgitation. Underneath the truncal valve, there is usually a large ventricular septal defect (VSD). Coronary anomalies can occur in TAC patients. More frequent associated anomalies include the right aortic arch (25 %), aberrant right subclavian artery (5–10 %), and interrupted aortic arch (10–15 %). Many patients with truncus arteriosus have DiGeorge syndrome (hypocalcemia risk).