Name : Noshin
Affiliation : Chamran Hospital
Academic Degree: Head of Radiolgy Department of Chamran Hospital
Resident : Ramin Pourghorban
Gender : Male
Age : 3
3 year-old boy with cyanosis
Post-contrast axial image (figure-1) reveals a defect between left atrium and left ventricle, implying VSD as well as right-sided descending aorta. Sagittal (figure-2) and axial (figure-3) MIP as well as 3D volume-rendered (figure-4) images demonstrate atresia of main pulmonary artery, accompanied by the presence of two large Major Aorto-Pulmonary Collateral Arteries (MAPCAs); one of them supplies the right pulmonary artery and the other supplies both right and left pulmonary arteries.
none (this is a pathognomonic feature)
Tetralogy of Fallot
Discussion (Related Text)
Tetralogy of Fallot is among the most common cyanotic heart diseases in children and accounts for approximately 4%??8% of all congenital cardiac lesions. Depending on the degree of obstruction of the right ventricular out-flow tract, bronchial and aortopulmonary collateral vessels may supply a variable amount of blood to the lungs. Tetralogy of Fallot is often associated with pulmonary artery atresia of various degrees of severity (from mild arterial hypoplasia to the complete absence of the main pulmonary artery or the nonconfluence of its branches). Other commonly associated anomalies are right-sided aortic arch, which is present in 25% of cases, and atrial septal defect, which is present in approximately 5% of cases. Ventricular septal defect, persistent left superior vena cava, coronary artery abnormalities, and aberrant right subclavian artery also have been noted. Rarely, tracheoesophageal fistula, rib anomalies, and scoliosis are present. MAPCAs represent fetal primitive intersegmental arteries that originate from the descending aorta and have not involuted. They gain access to the lung through the hilum and connect with native pulmonary arteries in the mediastinum or at the lobar or subsegmental level. MAPCAs are different from bronchial arteries in a number of ways. Usually, MAPCAs do not branch in their mediastinal course, whereas bronchial arteries provide mediastinal branches and, in some cases, branches to the spinal cord. MAPCAs anastomose with the intrapulmonary arteries typically at or near the pulmonary hilum instead of in the periphery. MAPCAs may accompany bronchi but do not form a nutritive plexus around bronchi. Unlike bronchial arteries, MAPCAs are virtually never connected to intercostal arteries. Most MAPCAs have an elastic wall structure resembling the pulmonary artery or aorta rather than bronchial arteries.
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