PDA is an acronym for patent ductus arteriosus. The ductus arteriosus is a normal opening in the fetal dog, cat and humans, for that matter.  This opening allows blood to bypass the lungs of the fetus, because the mother is oxygenating the blood for the puppies when they are in utero. Normally, this opening closes in the first few days of life, but in a small percentage of the population it remains open and leads to abnormal blood flow through the heart.

It is the most common congenital heart defect that we see in dogs. The most obvious finding is what is called a continuous heart murmur, or machinery murmur. Then it is confirmed with a cardiac ultrasound. It is more commonly seen in female dogs of the following breeds; Maltese, Pomeranians, Shelties, Poodles and Yorkies.  There has been a genetic link found in some breeds, so any dog with a PDA needs to be spayed or neutered to prevent passing it along to offspring.

Surgery requires us to go into the chest cavity and dissect out the structure and pass sutures around it to close it permanently. The vast majority of these cases are successful, 95% or more, but there is risk associated with dissecting out an abnormal vessel.  Once the procedure is done they are able to go on and live a happy and normal life. Without surgery, the majority of these animals will be gone before they reach a year old.