14/03/2022
Everyone meet Oki!! Gorgeous little Oki was diagnosed with a loud heart murmur at 11 weeks of age. An echocardiogram confirmed a congenital heart defect known as a patent ductus arteriosus, or PDA for short. PDA is the most common heart defect in puppies and results from failure of closure of the "ductus arteriosus" after birth. This condition can also occur in humans.
The ductus arteriosus is a communication between the aorta and pulmonary artery which allows the blood to bypass the pulmonary circulation in utero. This is because the foetus does not use the lungs to breathe and oxygen is supplied by the placenta. Once the puppy is born, the ductus will close and the blood will travel to the lungs for oxygenation. Unfortunately, occasionally, as in Oki's case, the ductus fails to close which means high pressure blood flow from the aorta is continuously being shunted into the pulmonary artery. Over time, this can place a great strain on the heart and result in irreversible structural changes. Reversal of the shunt can eventually occur which results in de-oxygenated blood entering the systemic circulation which is bad news indeed! Luckily for Oki, she has very vigilant owners who organised for an echocardiogram to be performed straight away! Oki was an extremely good girl for her echo and did not even require sedation. The echo was performed with her dad holding her throughout.
Luckily, surgery can be performed to close the ductus and if performed early enough, puppies can go on to lead a perfectly normal life.
Oki was then referred to the amazing team at SASH Adelaide for surgery with the wonderful Dr Andrew Dunn. She is recovering well and will have a check-up soon to ensure that everything is going according to plan. Stay tuned for more updates.
In the ultrasound images attached, we can see that the left side of the heart is overloaded (larger than normal). The spectral doppler shows continuous, high-velocity positive blood-flow into the pulmonary artery and the colour doppler shows high-velocity turbulent blood (mixed colour signal) entering the pulmonary artery.
LA - left atrium
LV - left ventricle
RA - right atrium
RV - right ventricle
PA - pulmonary artery
AO - aorta
PV - pulmonic valve