Today’s case is a 3 month old Toy Poodle with lethargy. Have a look at the images and post your interpretation in the comments section!
There is moderate left atrial enlargement visible on the lateral and d/v projections. The pulmonary arteries and veins are enlarged. The increased vascularity gives the lungs a more opaque appearance than normal. The aortic arch and main pulmonary artery appear enlarged on the d/v projection. There is decreased serosal detail within the viewable abdomen consistent with the patient’s age.
Pulmonary overcirculation – left to right shunt such as a PDA.
Patent ductus arteriosus
Patent ductus arteriosus (PDA) results from a failure of the ductus arteriosus to close after birth. This connection from the aorta to the pulmonary artery allows high pressure blood to flow back into the pulmonary artery. This large amount of extra blood causes volume overload and pulmonary overcirculation. Both the arteries and veins are enlarged.
After intravascular coil occlusion of the PDA, you can see the decrease in pulmonary circulation as much smaller vessels, and less opacity to the lungs. The coil is visible at the heart base.
Goodwin JK, Cooper RC, Jr. Understanding the pathophysiology of congenital heart defects. Veterinary Medicine 1992;87:650,668.
Stickle RL, Anderson LK. Diagnosis of common congenital heart anomalies in the dog using survey and nonselective contrast radiography. Veterinary Radiology 1987;28:6-12.