DOI: https://doi.org/10.36347/sjmcr.2026.v14i05.099

Pages: 1275-1285

Truncus arteriosus is a rare congenital heart defect in which a single arterial trunk emerges from the heart, giving rise to the coronary arteries, pulmonary arteries, and the aorta. Its association with DiGeorge syndrome (also known as 22q11 microdeletion syndrome) is common. In addition to conotruncal cardiac malformations, this syndrome is associated with facial dysmorphia, thymic agenesis, absence of parathyroid glands with hypocalcemia. The diagnosis of truncus arteriosus should be clinically suspected in the presence of refractory cyanosis and a double cardiac murmur, and confirmed by echocardiography and/or thoracic CT angiography. A precise morphological description of the malformation and associated anomalies is mandatory to assist the surgeon in selecting the optimal timing and surgical technique. Thoracic CT angiography, as a complement to echocardiography, fulfills this objective. The prognosis without treatment is poor, with high mortality due to cardiac failure and severe pulmonary arterial hypertension. Treatment is surgical and consists essentially of closing the interventricular communication, detaching the pulmonary arteries from the truncus, and restoring continuity between the right ventricle and the pulmonary arterial branches, within the first three months of life. Prognosis has now improved thanks to new surgical techniques. We report the case of a three-month-old child admitted for afebrile seizures with hypocalcemia. Chest radiograph showed cardiomegaly, and echocardiography raised suspicion of truncus arteriosus. The diagnosis was confirmed by thoracic CT angiography with better characterization, revealing a Van Praagh type A2 truncus arteriosus with interventricular communication, right aortic arch, anomalies of the supra-aortic trunks with a retro-esophageal left subclavian artery. The diagnosis of 22q11 microdeletion syndrome was subsequently confirmed.