This information aims to give you an understanding of the Fontan Circulation and the important things to remember.
What is the Fontan Operation?
The normal heart has 2 ventricles (pumping chambers). The right ventricle pumps blood that is low in oxygen (blue blood) to the lungs and the left ventricle pumps blood that has lots of oxygen (red blood) to the body.
Sometimes the heart forms with only one ventricle that has to pump blood to both the lungs and the body. When there is only one ventricle, the blood pumped to the body is low in oxygen. The Fontan operation is performed on people with these heart conditions.
The aim of the Fontan operation is to separate the blood to ensure that only blue blood goes to the lungs and red blood is pumped to the body. This is done by connecting the veins that carry blue blood returning from the body directly to the lungs.
This means that all of the blue blood returning from the body goes to the lungs where it picks up oxygen. Blood that is full of oxygen then goes to the heart and is pumped to the body.
The difference to the normal situation is that blue blood gets to the lungs without being pumped there.
Why is long-term follow up needed?
All people with a Fontan circulation require life-long follow up. Complications become more common over time. These include problems with the heart rhythm (e.g. too fast, too slow or irregular), blood clots, liver problems and a decline in heart function.
A number of tests may be performed to assess how well your heart is doing and whether any new treatments or procedures would be advised. These include echocardiograms (ultrasound scans of the heart), blood tests, liver ultrasound scans, MRI scans, exercise tests and cardiac catheter tests.
The Fontan Circulation and the liver
People with a Fontan Circulation are at risk of developing liver disease. This is called Fontan Associated Liver Disease.
The pressure in the veins is higher in a person with a Fontan circulation than usual. This higher pressure is necessary to drive blood through the lungs. However, the higher pressure affects the ease with which blood leaves the liver and this can result in changes in the liver over time. Commonly the liver develops scarring which may remain mild and stable or may progress to more serious problems as people age. It is thought that most patients with a Fontan circulation have some degree of Fontan Associated Liver Disease by the time they reach adulthood.
We look for Fontan Associated Liver Disease in a number of ways. This usually involves liver ultrasound scans and blood tests. Sometimes liver MRI scans or camera tests are required too. The results are regularly discussed in a meeting with the cardiologists and the hepatologists (liver specialists).
Back to topWatch this video for a visual explanation of the Fontan Circulation
Understanding the Fontan Circulation
This video has been developed to help you understand the Fontan circulation in more detail. The normal heart has two ventricles, which are pumping chambers. The right ventricle pumps blood that is low in oxygen, known as blue blood, to the lungs. The left ventricle pumps blood that has lots of oxygen, known as red blood, to the body. Sometimes the heart forms with only one ventricle that has to pump blood to both the lungs and the body. When there is only one ventricle, the blood pumped to the body is low in oxygen. These are called single ventricle conditions.
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The Fontan operation is performed on people with these heart conditions. The aim of the Fontan operation is to separate the blood to ensure that only blue blood goes to the lungs and red blood is pumped to the body. This is done by connecting the veins that carry blood low in oxygen from the body directly to the lungs where it picks up oxygen. Blood that is full of oxygen then goes to the heart and is pumped to the body.
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The difference to the normal heart is that blue blood gets to the lungs without being pumped there. Because there is no pump to the lungs, the way blood gets around the heart and the body is different and there are some problems that can occur. People with a Fontan circulation may get problems with their heart rhythm as they get older. The heart might beat too fast, too slow, or irregularly. This can cause unwanted symptoms and sometimes needs medication, electric shock therapy, or more advanced treatments like pacemakers.
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People with a Fontan circulation only have one ventricle. Over time, the ventricle can become weaker and pump less forcefully. Sometimes problems with the Fontan circuit itself can occur. There can be narrowing’s or blockages in the circuit and sometimes extra blood vessels may develop. These are called collaterals and can cause people to be low in oxygen. These problems may need treating in a keyhole procedure.
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People with a Fontan circulation are at risk of blood clots, so they need to take blood-thinning medications lifelong. Because there is no pump to the lungs, the pressure in the veins is higher. The Fontan circulation relies on this higher pressure so that blood can be driven through the lungs and back to the heart. However, the higher pressure makes it harder for blood to leave the liver. This can cause changes in the liver over time such as scarring. This is called Fontan-associated liver disease and will be monitored in various ways.
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If you have any questions about any of the information in this video, please speak to your medical team
Medicines
People with a Fontan circulation are at risk of developing blood clots. To help prevent these, most patients are routinely prescribed blood thinning medicines, such as warfarin, or other similar drugs.
Other medicines might also be used, for example to help heart function or to control heart rhythm problems.
Pregnancy and contraception
Women with a Fontan circulation can have successful pregnancies, but a number of complications can occur, so careful planning and close monitoring are required. If you are considering pregnancy it is important that you speak to your cardiologist so that you are fully aware of the issues.
Warfarin and some other blood thinning medication can be harmful to the baby. Therefore, an alternative form of blood thinning medication may be necessary for certain stages of the pregnancy. If you become pregnant you should let us know as soon as possible.
Women with a Fontan circulation should avoid contraception that contains the female hormone oestrogen, such as the combined oral contraceptive pill. Contraceptives that contain progesterone only are suitable, for example the progesterone only pill or the contraceptive implant. Please speak to your doctor or a specialist nurse if you need advice about this.
For both men and women, the chance of having a child born with a heart problem is slightly higher than normal because you have a heart problem yourself. We can offer a specialised scan of your unborn baby’s heart at 18-20 weeks, which can detect any major abnormality of the heart.
Endocarditis
All patients with congenital heart disease are at risk of infection in the heart (endocarditis). The most common way bacteria can get into the blood stream and not onto the heart is through the mouth, so it is important to practice good dental hygiene and visit the dentist every 12 months.
Some people require antibiotics before invasive dental treatment. Please ask your doctor or specialist nurse if this applies to you. Due to the increased risk of infection we would also advise against body piercing and tattoos.
Insurance
It can be difficult for people who have congenital heart disease to get insurance. This can cause travel insurance to be a bit more expensive and may cause problems when trying to get life insurance. There are some more sympathetic insurers who can be identified and contacted through the Somerville Heart Foundation. We would recommend seeking advice from a specialist insurance advisor before applying for life insurance.
Back to topLifestyle
Everyone should aim to stay a healthy weight. This is probably even more important for people with a Fontan circulation to keep your heart pumping well in the long-term.
There is some evidence that having good muscle strength can help blood flow back to the lungs more efficiently. Doing regular exercise to a moderate level, including light-medium weights is good for your overall cardiovascular fitness and for your Fontan circulation. We can put you in touch with our specialist physiotherapist if you require more advice about exercise.
The Fontan circulation relies on health lungs so it is important not to smoke.
Alcohol can affect the liver. Due to the risk of Fontan Associated Liver Disease it would be best to avoid alcohol completely if you can. If you do choose to drink alcohol, try to avoid regular binge drinking and try to stay within the nationally recommended limits of less than 14 units per week. Staying well hydrated, especially if you are unwell with a cold or other illness is also very important.
Other advice
People with a Fontan circulation may have lower than normal levels of oxygen in the blood (oxygen saturations). It is important that you know what is normal for you.
We encourage you to keep copies of your clinic letters and your ECG (you could take photos of these on your phone) so that if you ever need to be seen by a different medical team you can give them the correct information. If you need a non-cardiac operation this should be discussed with your cardiologist first.
Contact us
For clinical queries
ACHD Specialist Nurses
Please contact the ACHD Specialist Nurses.
Further Support and Advice
The Somerville Heart Foundation
For young people and adults with congenital heart disease.
Join as a ‘friend’ to access their benefits including advice around benefits, employment, pensions, will writing and insurance. They also have a counselling service and support groups.