Patent ductus arteriosus

What is Patent Ductus Arteriosus or PDA?  What does it do?  What causes it?  How will I know if my dog has it?  What can be done?

These are all questions that any pet owner has for any disease or defect that they find out their little bundle of fur may have, not only PDA.  This page is about PDA.  

I was not even aware of this defect until a friend had a seemly, healthy puppy die from it suddenly.  I have had dogs and cats in my life for the past 38 years and this was the first time I heard of it, which of course prompted me to do some research on my own about it, in case I ever had the misfortune to have an experience with it. 

From the research I have done on the internet, at the library, and also from information found in medical books that belong to my daughter, who is an FNP (Family Nurse Practioner),  and Home Veterinary hand books, Patent Ductus Arteriosus is in every mammal at birth.  It is a duct that blood flows through while the fetus is still using the mothers oxygen supply.  When the baby is born and starts to breath this duct is supposed to close.  It should close with in a few hours to a few days.  All of the information that I have gathered give one to several, reasons that it might not.   Some are genetic, and some are classified as random events.   Some are even classified as polygenetic.

Causes listed for both human and animal are;

• Prematurely
• Congenital           (present at birth)
• Hypoxia                (lack of oxygen)
• Prostaglandins     (biochemical's in the body)

PDA is usually detected by your veterinarian when he hears a continuous machinery heart murmur during a check-up.  Then there are tests that are done to confirm it.  PDA is the most common congenital heart defect in dogs.

Symptoms of PDA are

• Inactivity
• During periods of excitement shortness of breath and possible collapse
• The gums may appear bluish, because of the shortage of oxygen
• A murmur can sometimes be heard without a stethoscope

The treatment of PDA calls for surgery that involves tying the ductus arteriosus.  Surgery is very successful and is best done early.

Without treatment the final outcome is death.  Some puppies will live only a few weeks, while others can live longer.   

There are conflicting opinions on how, and why it shows up in a dog.  After all the searching and reading, I still do not know who is right.  Some of the experts say it is hereditary and passed down through the parents, others say it is unknown why it happens.  Yet some will say it depends on the history of the breeding pair that produced the PDA pup.  I think that all possibilities need to be taken into consideration when you have the misfortune to experience this.  Look back through the breeding line history, ask if there were any unusual events that may have occurred during the birth, find out if any of the siblings have any problems.  Check into previous births of the pair and see if it happened before.   Confer with your vet, or a specialist that your vet might recommend.  Gather all the information you can get before making your decision on the cause, and how you are going to handle the situation with your dog.

Please remember, your best source of help for any health problem with your pet is your veterinarian.  Never take advice from anywhere or anyone without checking with him/her about it.