Pediatric Patent Ductus Arteriosus

Etiology: Failure of closure of the fetal ductus arteriosus connecting the main pulmonary artery to the descending aorta leading to a left to right shunt
Imaging: Intracardiac left to right shunt leads to acyanosis and increased pulmonary blood flow
Imaging CXR: Cardiomegaly and increased pulmonary blood flow that increases over time
Imaging Angiogram: Simultaneous filling of the pulmonary artery and aorta when either is injected
Note: 33% have a ductus diverticulum which is a developmental outpouching of aortic isthmus where ductus arteriosus attaches on anteromedial aorta which also happens to be the site of 90% of post-traumatic aortic injuries so it should not be mistaken for a traumatic aortic pseudoaneurysm
— Ductus diverticulum’s angle of origin from aorta is obtuse and rounded
DDX: Traumatic aortic pseudoaneurysm
Complications: Prostaglandin E – keeps patent ductus arteriosus open in patent ductus arteriosus dependent congenital heart diseases (pulmonary atresia, hypoplastic left heart syndrome)
— Can cause periostitis and gastric mucosal hypertrophy mimicing hypertrophic pyloric stenosis
Complications: Indomethacin – closes patent ductus arteriosus
— Can cause gastrointestinal perforation
Treatment:
Clinical:
— In fetus gas exchange occurs at placenta and thus ductus arteriosus allows oxygenated blood from placenta to bypass high resistance pulmonary bed and enter systemic circulation
— Usually closes within 24-48 hours of birth in term neonate
— Acyanotic

Radiology Cases of Patent Ductus Arteriosus

CXR AP at 1 day of life (above) and 1 year of life (below) shows interval development of cardiomegaly and pulmonary vascular congestion.

CXR of patent ductus arteriosus — CXR AP shows cardiomegaly and increased pulmonary blood flow.

CXR of patent ductus arteriosus ductus diverticulum — CXR AP shows mild cardiomegaly and pulmonary vascular congestion along with an extra soft tissue mass just to the left of the spine near the presumed position of the ductus arteriosus.

Angiogram of patent ductus arteriosus — AP angiogram while injecting the pulmonary artery shows simultaneous filling of the descending aorta.

Angiogram of patent ductus arteriosus / PDA — AP image from a ventricular injection in an angiogram shows simultaneous opacification of the aorta and main pulmonary artery.

Angiogram of patent ductus arteriosus — AP (left) and lateral (right) images from an angiogram with the catheter in the aortic arch shows simultaneous opacification of the aorta and the main pulmonary artery.

Radiology Cases of Patent Ductus Arteriosus Due to Interrupted Aortic Arch

CT of interrupted aortic arch — Axial CT with contrast of the heart (above), obtained in a venous phase, shows discontinuity of the ascending and descending aorta while the sagittal image (below right) shows a dilated patent ductus arteriosus reconstituting the descending aorta and the coronal image (below left) shows dextrocardia.

Radiology Cases of Patent Ductus Arteriosus Due to Preductal Coarctation of the Aorta

3D CT of preductal coarctation of the aorta — 3D CT with contrast of the aorta viewed posteriorly (left) shows diffuse narrowing of the aortic arch until its junction with the descending aorta. 3D CT viewed anteriorly (right) shows a huge patent ductus arteriosus joining into the descending aorta.

Radiology Cases of Accidental Clipping of the Left Mainstem Bronchus Along With the Patent Ductus Arteriosus

CXR of PDA clip on left mainstem bronchus — Preoperative CXR AP (above left) shows mild cardiomegaly and increased pulmonary vascularity. Postoperative CXR AP (above right) shows interval placement of a rather large clip on the ductus arteriosus. There is interval development of complete collapse of the left lung. CXR AP obtained after remove of the clip (below) shows interval reexpansion of the left lung.