Name : Noshin
Affiliation : Chamran Hospital
Academic Degree: Head of Radiology Department of Chamran Hospital
Resident : Ramin Pourghorban, Ensi Khalili pouya
Gender : Male
Age : 8
8 year-old boy with dyspnea
MPR, MIP and 3D volume rendering CT images in oblique sagittal and axial views show an arterial branch (arrow on image-3) running between the aorta and the pulmonary artery implying Patent Dactus Arteriosus.
Discussion (Related Text)
The ductus arteriosus derives from the left sixth primitive aortic arch and connects the proximal left pulmonary artery to the descending aorta, just distal to the left subclavian artery. The ductus is widely patent in the normal fetus, carrying unoxygenated blood from the right ventricle through the descending aorta to the placenta, where the blood is oxygenated. Functional closure of the ductus from vasoconstriction occurs shortly after a term birth, whereas anatomical closure from intimal proliferation and fibrosis takes several weeks to complete. The ductus arteriosus often remains open rather longer in premature infants, but in the majority of cases it still closes spontaneously. If there is a persistent failure of closure of the duct, then the consequences will depend on the size of the communication. A tiny residual patent ductus arteriosus (PDA) can remain undiagnosed throughout life as it will produce minimal effects. A large PDA will have similar effects to a large VSD. With pressure and volume overloading of the pulmonary circulation. In most diagnosed cases the PDA is commonly associated with many other congenital cardiac abnormalities, and no investigation of congenital heart disease is complete without diagnosis of a coexisting PDA. The clinical sign of a continuous murmur is classically associated with a PDA, but coronary artery fistulas and a ruptured sinus of Valsalva can also give a continuous murmur, and must be distinguished from PDA by echocardiography or angiography. Although a large PDA may be visible on CT scanning or CT angiography, CT scan studies have only limited value because of the need to use ionizing radiation and, usually, contrast agents. Occasionally, calcification in the PDA is demonstrated in a characteristic position. CT scanning may be used to image the aorta in an evaluation of the chest for possible aneurysms; this is when ductus arteriosus aneurysm may be detected.
Patent Dactus Arteriosus
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