May 3, 2017
izzie had xrays that showed enlargement of the heart which prompted Lizzie’s vet to send her to Allied for an ultrasound of the heart (echocardiogram) to determine if there was a heart defect. The echocardiogram was performed that day and confirmed a birth defect known as Patent Ductus Arteriosus.
Patent Ductus Arteriosus (PDA) is a condition where there is incomplete development of the heart. A single vessel called the ductus arteriosus fails to close as it should at birth – this vessel is necessary in the developing baby because there is no air to breath in the womb. The ductus arteriosus is a blood vessel that ensures the blood (which already has oxygen supplied by mom) does not circulate to the developing lungs. This all changes at birth when the first breath of air is taken. The lungs, now fully developed, will provide the oxygen for the newborn. In the presence of air the ductus arteriosus will close and blood now flows the way it is supposed to – from the right side of the heart to the lungs and then back to the left side of the heart. From there the oxygenated blood can be sent out to the body. Except when the ductus arteriosus doesn’t close the way it is should (or remains “patent”). This results in serious, and often life-threatening changes to the normal flow of blood through the heart. In the absence of treatment the majority of animals do not survive a year.
diagnosis of a birth defect of the heart is pretty devastating. However, in the case of PDA there are actually treatment options that can be successful in curing the condition. The goal of these treatments is to occlude or close the ductus arteriosus. In humans a technique called coil embolization has been perfected in which a catheter is passed up to the heart and a device, or “coil” is released into the ductus. This coil sticks in the vessel and stimulates a blood clot which will quickly prevent blood from passing through the ductus. The traditional treatment in veterinary medicine is a thoracotomy – in which a surgeon opens the chest, visualizes the ductus and closes by tying a suture around the vessel.
It’s safe to say that both procedures are extremely delicate and require a highly skilled and experienced operator to be successful. That being said, pets with PDA that are treated with coil or surgical ligation have a better than 95% of cure and can go on to live a completely normal life!