Frankie's Heart Problem: Patent Ductus Arteriosus, PDA
While a puppy is in the womb, there is no air in his lungs. Blood flows through the heart, through the lungs to a small extent, and through the rest of the body. Oxygen comes from the mother via the puppy's placenta. The heart looks like the diagram.
The Patent Ductus allows blood from the right ventricle to reach the left atrium.
After the puppy is born, the Patent Ductus (the connection from right ventricle to left atrium) normally closes within 24 hours. After that all the blood from the right ventricle goes through the lungs and becomes oxygenated.
Frankie's Patent Ductus Arteriosus did not close. So his blood was not being properly oxygenated.
The Amplatz Canine Duct Occluder (ACDO) is a mesh that is inserted in the Patent Ductus to close it. The mesh is inserted through an artery.