Patent Ductus Arteriosus (PDA)
Information for teenagers and adults with a patent ductus arteriosus
A patent ductus arteriosus (PDA) is a persistent connection between two of the major blood vessels leaving the heart — the aorta and the pulmonary artery.
The ductus arteriosus is a normal and important blood vessel before birth. It allows blood to bypass the baby’s lungs while oxygen is supplied by the placenta. Normally, the ductus closes shortly after birth. If it remains open, it is called a patent ductus arteriosus.
Many PDAs are diagnosed and treated during childhood. However, a small PDA may occasionally be discovered for the first time in adulthood.
For most people with a small or successfully closed PDA, the outlook is excellent.
How does a PDA affect the circulation?
After birth, the pulmonary artery carries blood from the right side of the heart to the lungs, while the aorta carries oxygen-rich blood from the left side of the heart to the rest of the body.
Because pressure is normally higher in the aorta than in the pulmonary artery, an open ductus usually allows blood to flow from the aorta into the pulmonary artery.
This means that some blood which has already passed through the lungs is directed back through the lungs again.
The effect depends mainly on the size of the PDA.
A small PDA may allow very little additional blood flow and cause no symptoms or enlargement of the heart.
A larger PDA can result in increased blood flow through the lungs and increased work for the left side of the heart. Over time, this can cause enlargement of the heart and, in some people, increased pressure in the blood vessels of the lungs (pulmonary hypertension).
Does a PDA need to be closed?
Not every PDA requires treatment, although closure is recommended when a PDA is causing significant extra blood flow through the lungs or enlargement of the left side of the heart.
Most PDAs that require treatment can now be closed using a catheter procedure, avoiding open-heart surgery.
During the procedure, a thin tube is passed through a blood vessel, usually from the groin, to the heart. A small plug or coil is then positioned within the PDA to stop blood flowing through it.
Surgery is now required much less commonly but may occasionally be recommended if the anatomy is not suitable for catheter closure.
Very small PDAs that are not causing heart enlargement may not require closure and can sometimes simply be observed.
If severe pulmonary hypertension has developed, careful specialist assessment is required before considering closure. In some people with advanced and irreversible pulmonary vascular disease, closing the PDA may be harmful rather than beneficial.
Your congenital cardiologist can determine whether your PDA requires treatment.
What is Eisenmenger syndrome?
Very rarely, a large PDA that remains untreated for many years can cause severe and irreversible damage to the blood vessels in the lungs.
As the pressure in the lung circulation rises, blood flow through the PDA can eventually reverse, travelling from the pulmonary artery into the aorta. This is known as Eisenmenger syndrome.
This can cause low oxygen levels, breathlessness and a blue or purple appearance of the lips or fingers (cyanosis).
Eisenmenger syndrome is now uncommon in Australia because significant PDAs are usually identified and treated much earlier. People with this condition require lifelong care through a specialist adult congenital heart disease and pulmonary hypertension service.
How to stay well
Keep up with your heart checks
The amount of follow-up required depends on the size of the PDA, whether it has been closed and whether there are any associated heart or lung circulation problems.
After successful PDA closure with no residual leak and normal heart function, some people may require little or no long-term specialist follow-up.
People with a residual PDA, enlargement of the heart, pulmonary hypertension or other congenital heart abnormalities require ongoing review.
Stay active
Most people with a small or successfully closed PDA can undertake normal physical activity and exercise without restriction.
Exercise recommendations may be different if you have significant pulmonary hypertension, abnormal heart function or another associated heart condition.
Your cardiologist can provide individual advice if you are considering particularly strenuous or competitive exercise.
Look after your teeth
Good dental hygiene is an important part of looking after your heart.
People with congenital heart disease have a small lifetime risk of infective endocarditis, an infection involving the inner lining or valves of the heart.
Most people with a PDA do not require antibiotics before routine dental treatment. Antibiotic prophylaxis may be recommended for a limited period after device or surgical closure, or if there is a residual defect associated with prosthetic material. It is also recommended for some people with a previous history of infective endocarditis.
Your cardiologist or dentist can tell you whether this applies to you.
Don’t smoke or vape
Smoking increases the risk of cardiovascular and lung disease. Avoid smoking and vaping and seek help to quit if needed.
Pregnancy
Most women with a small or successfully closed PDA, normal heart function and normal pulmonary artery pressure can have a successful pregnancy with relatively low cardiovascular risk.
It is sensible to discuss pregnancy with your cardiologist beforehand if you have an unrepaired PDA or have not had a recent cardiac assessment.
Pregnancy is considerably more complicated when significant pulmonary hypertension is present. Severe pulmonary arterial hypertension or Eisenmenger syndrome makes pregnancy extremely high risk and requires specialist pre-pregnancy counselling.
Symptoms to tell your doctor about
Contact your doctor or cardiology team if you develop:
New or increasing shortness of breath
A noticeable reduction in your exercise capacity
Frequent or prolonged palpitations
New swelling of your ankles or abdomen
Unexplained fainting or near-fainting
Persistent unexplained fevers
A significant change in your usual symptoms
Persistent unexplained fever is important because, although uncommon, it can be a symptom of infective endocarditis.
Emergency — get help immediately if
Seek urgent medical attention or call 000 if you develop:
Severe or sudden shortness of breath
Fainting associated with chest pain, breathlessness or sustained palpitations
A sustained rapid heartbeat associated with dizziness, chest pain or feeling very unwell
Sudden severe chest pain or a significant deterioration in your condition
High fever with shaking chills and feeling seriously unwell
Your regular check-ups
Depending on your PDA and whether it has been closed, your follow-up may include:
Clinical review
Your cardiologist will ask about your exercise capacity and symptoms and examine your heart and circulation.
ECG
An electrocardiogram records the electrical activity and rhythm of your heart.
Echocardiogram
An ultrasound of the heart can assess heart size and function, pulmonary artery pressure and blood flow through a PDA or around a previous closure device.
Cardiac CT or MRI
These are not routinely required but can provide additional information about the PDA, aorta, pulmonary arteries or heart when needed.
Cardiac catheterisation
This is commonly used when closing a PDA with a device. It may also be required to accurately measure pressures and resistance within the lung circulation when pulmonary hypertension is suspected.
Questions for your doctor
Is my PDA still open?
Is it causing enlargement of my heart or increased pressure in my lungs?
Does my PDA need to be closed?
If it needs closure, can this be done with a catheter procedure?
Do I have any restrictions on exercise, work, travel or pregnancy?
How often should I have a heart check-up?
This information is intended as a general guide for teenagers and adults with a patent ductus arteriosus. Individual congenital heart conditions vary, and your cardiologist can provide advice specific to your anatomy, previous treatment and current health.
