Children with complex heart conditions can be offered a variety of treatments and interventions to improve their heart function. On the following pages a number of different treatments are described.
It is important to remember that not all of them will be appropriate for every child and that in many cases they are staged through a child’s or young adults life.
- Arrhythmias and pacemakers
- Ballooning valves and arteries
- Cardiac tests
- Cavo-Pulmonary Connection (Stage Two) for all single ventricle conditions
- The Damus Procedure
- Dental care and sub-acute bacterial endocarditis
- ECMO or ECLS (Extracorporeal Membrane Oxygenation or Extracorporeal Life Support)
- The Fontan Procedure (Stage Three) for all single ventricle conditions or completion of the Cavo-Pulmonary Connection
- Heart failure
- The Hybrid Procedure
- Inserting a stent
- MCT diet
- Modified Norwood Procedure (Stage One)
- Modified Norwood Procedure (Norwood with a Sano Shunt)
- Possible complications
- Preparation for hospital
- Surgical treatments for right-sided single ventricle conditions
- Heart transplantation
Doctors have a number of medications that they can use to control clotting after surgery and then onward into life at home. These medications are called anticoagulants. The amount of medication a child or young adult needs to control their clotting is called the level of anticoagulation.
Anticoagulation can be prescribed by a cardiologist, cardiac surgeon, a haematologist (a doctor who specialises in blood-related conditions) or a specialist haematology or cardiac nurse. This could be at the cardiology centre, the local hospital or the GP clinic.
Heparin is a medication that is a very strong anticoagulant. It can only be given by either intravenous injection or infusion (injection into a vein) or subcutaneous injection (injection into the skin). The main advantage of Heparin is that the degree of anticoagulation is tightly controlled and can be increased or decreased almost immediately. The disadvanatage is that it cannot be taken by mouth.
Most children and young adults are started on a Heparin infusion (given by drip) at the end of their operation so that the doctors and nurses can control clotting immediately after surgery.
This medication is usually stopped once the child or young adult has recovered well enough to be swapped to medication they can take by mouth and the level of this longer-term anticoagulation, that the child or young adult will go home on, has reached the target set by doctors.
Occasionally a child or young adult may need a further course of Heparin because their anticoagulation is not controlled or to provide anticoagulation that then can be controlled quickly if this is required (for example, if the child or young adult needs a non-cardiac procedure). This will be given either by infusion (drip) or by injection. Sometimes children or young adults are sent home on Heparin; either a nurse will come into the home or the patient or the parents of the child themselves can learn to give the injection.
Aspirin is a medication that stops red blood cells and platelets sticking together (antiplatelet). It is often the drug of choice in patients after the first stage of single ventricle heart surgery (patients with a shunt, Norwood Stage One or a stent) to prevent the blood sticking together on the surface of the shunt or stent.
To prevent stomach irritation, Aspirin should be given after a meal or with a glass of milk.
Some medications may be used together with Aspirin.
As a general rule, Aspirin is not given to children because there are risks of a child contracting Reye’s Syndrome, or the medication irritating the stomach lining. However, if it is prescribed for a child with a complex heart condition, it is because it is the drug of choice and the benefits will far outweigh the risks. Although the effectiveness of Aspirin is not usually monitored (in the same way Warfarin is), more recently, a method known as platelet thromboelastography (TEG) has been developed to assess how well it is working. This is done as a blood test. In small babies, particularly after Stage One surgery, some units will check the platelet TEG to alter the dose of Aspirin or consider adding another antiplatelet medication.
Dipyridamole is another antiplatelet similar to Aspirin and is often used with Aspirin. It also works as a vasodilator, i.e. it opens up blood vessels, so it is used to reduce high blood pressure, especially in the lungs. Sometimes this drug can be the medication of choice in a child or young adult who needs both vasodilation and anticoagulation. It can be given by mouth at home.
Clopidogrel is another antiplatelet similar to Aspirin. Sometimes this medication is used in place of low levels of Aspirin but it is also used at the same time as Aspirin because the two work well together, particularly after Stage One surgery or when a stent has been put in. This medication can be given by mouth at home.
NOACS (Novel Oral Anticoagulants). Over the last few years several new anticoagulant drugs have been developed for patients with acquired heart disease (heart disease that happens later in life), in particular, heart rhythm problems, as an alternative to warfarin. They have been shown to be as effective as Warfarin in stopping the blood clotting in these situations.
Examples include Apixaban, Dabigatran and Rivaroxaban. The main advantage is that no blood tests are required. Some units prescribe these in young adults with single ventricle/Fontan circulations instead of Warfarin or antiplatelet medication. Although there is is still not much experience of these medications in single ventricle circulations compared to Warfarin and antiplatelets, these medications hold promise for all patients who require anticoagulation and further developments are taking place. If your cardiologist suggests one of these medications, talk to them about the benefits and risks.
Warfarin is an oral medication (given by mouth) that slows down the blood’s ability to create the meshwork of a clot (form scabs).
Anyone on Warfarin needs to be careful if they bump themselves or have a cut as they will bleed for longer than normal.
The main advantage to Warfarin is that it provides a reliable high level of anticoagulation. However, on occasions the body does not use up the whole daily dose so it can have an accumulative effect which affects clotting time. Regular blood tests are needed to check the current clotting time. This is referred to as the INR (International Normalised Ratio). Alterations in the daily dose will be made to keep the clotting times in line with the doctor’s clotting limits and the safety of the patient. A positive reason to use this medication is that bleeding can be swiftly reversed in the case of an accident.
For more information see LHM’s Living with Anticoagulation booklet.
Arrhythmias and pacemakers
All hearts have a heartbeat, which is the electrical message that passes through the heart and tells the heart muscle to push blood from one section of the heart to another and then out of the heart to the circulation. The beat (pulse) created depends on the body’s activity, so at rest the rate is lower and on exercise it becomes faster. Children and adults with congenital heart conditions may have a disturbed heart rhythm (arrhythmia). Sometimes they are born with an arrhythmia, sometimes one develops.
Many children who have had major heart surgery have a disturbed heart rhythm after their operations. These are usually temporary and are solved as the heart recovers from the surgery but in some cases the heart rhythm does not recover and a more permanent solution will need to be found. The first treatment offered will often be medications to control the heartbeat. This may solve the problem and no further intervention will be needed. For some children and young adults other solutions will be explored.
Ablating an electrical pathway
In some patients the electrical pathway will be disturbed so that heart rhythm messages will be sent to the wrong part of the heart, which creates an imbalance with the pumping of the heart muscle. In these cases cardiologists may offer ablation as a treatment. This is a treatment undertaken under anaesthetic in the cardiac catheterisation theatre. Cardiologists identify the pathways of faulty electrical activity and block the ones that are creating an imbalance. This may be done by either a freezing or burning process.
If an arrhythmia (abnormal heart rhythm) persists and affects the heart function doctors may decide to insert a pacemaker. There are a number of different pacemakers that solve different problems. Some help to regulate the heartbeat, others send an impulse to the heart when there are long pauses between beats. Surgery will be needed to insert the pacemaker but it is not as complex as open heart operations. The pacemaker box is either placed in the abdomen, especially in smaller children, or under the arm or chest muscles in an older/bigger patient.
Following a pacemaker insertion regular pacemaker checks will be set in place. Changes to the pacemaker settings can be made externally so there is no need for further invasive intervention until the pacemaker box needs changing – usually at around ten-year intervals.
Ballooning valves and arteries
Children who have malformations within the heart requiring reconstruction of blood vessels often develop a narrowing around the site of surgery or the malformation. To ensure that blood can flow freely through the blood vessels cardiologists often balloon the area of the narrowing to stretch it back to normal or nearly normal size. The ballooning takes place during a cardiac catheterisation (see Cardiac Tests below). Most children have this procedure done under a light anaesthetic and they will be in hospital for an overnight stay.
This is a simple painless test where a plastic strip or clip is attached to a finger or foot to measure the amount of oxygen circulating in the blood of babies, children and adults. It is particularly important for children with complex heart conditions who are blue (cyanosed) because of the low oxygen levels as it helps the medical team to plan their treatment and care.
Blood is a very important part of the circulation because it carries all sorts of things around the body: oxygen, nutrients and chemicals. Taking samples of blood can be a very helpful way of monitoring how well a baby, child or adult is and how the body is coping with an illness or long-term condition.
For doctors to see if a baby, child or adult’s chest is healthy, especially before and after surgery, the easiest test is to take an x-ray of the chest so that they can see how the chest is healing but also to look for infections or fluid collections in the lung area. These tests help plan treatment and post-surgery recovery support.
Echocardiography uses sound waves to scan the heart which is then shown as a picture. This is the same type of scan that mothers have during pregnancy. The test does not hurt, but children sometimes have a light sleeping medicine (sedative) so that they stay still. This is the first test that will be done on the baby, as it is the easiest and least stressful way of making a diagnosis of congenital heart disease.
Electrocardiography (ECG) is the recording of the electrical activity of the heart. The heart has its own electrical system, which passes the message to beat through the heart’s muscle tissue. Sometimes the message breaks down and so by recording the rhythm, the medical team can see if the messages are being passed properly. It is also possible to assess the size of the pumping chamber and the thickness of the heart wall.
Cavo-Pulmonary Connection (Stage Two) for all single ventricle conditions
Bi-directional Cavo-Pulmonary Shunt (Glenn Shunt) or The Hemi-Fontan Operation
As the children grow, they will require a more permanent supply of blood to their lungs than earlier surgical procedures can provide. A Cavo-Pulmonary Connection is normally performed between three and twelve months of age.
The aim of this operation is to redirect the flow of blue blood (deoxygenated blood) to the lungs by attaching the upper body vein (superior vena cava) directly on to the lung artery (pulmonary artery). The Gore-Tex shunt or band that was inserted at the last operation will be taken away.
In some centres the stump of the lower body vein (inferior vena cava) is attached to the base of the lung artery (pulmonary artery). This is known as the Hemi-Fontan operation. Although blood does not flow through this attachment at this time, it prepares the child for the completion of a Fontan procedure at Stage Three.
These operations have fewer risks than the first stage but it is important to talk with the medical team to find out the risks for your child.
Children who are born with complex congenital heart disease associated with a reduced blood flow to their lungs can sometimes develop collateral vessels.
What are collaterals?
If a baby is born with a malformation of the heart and a lack of blood flowing to the lungs to collect oxygen, the child will have low oxygen saturations (the amount of oxygen in their blood). They will be cyanosed (have blue-coloured lips and fingernails) and may be breathless on mild exercise or feeding. Collaterals are connections, like normal blood vessels, that can develop in children with cyanotic heart disease such as single ventricle heart conditions.
There are two types of collaterals:
Systemic Arterial Collaterals
These abnormal vessels originate from the body blood vessels, in particular the aorta, and grow towards the lungs. They can form when a child has had a long period of cyanosis (low oxygen levels in the blood which create blue lips and fingernails). The collaterals aim to take more blood to the lungs where it can collect oxygen. This is the body’s response to the long-standing low oxygen saturations. These collaterals make the child less blue but create more work for
Systemic Venous Collaterals
These are abnormal blood vessels that originate from the veins taking the blue (deoxygenated) blood back to the heart. They normally develop after the second operation, the Cavo-Pulmonary Connection (or Stage Two). After this operation the pressure in the veins in the upper body is greater than the pressure in the veins in the lower body. With that, small veins can enlarge and can allow blue (deoxygenated) blood from the upper body to run down to the lower body rather than having to squeeze through the lungs. These collaterals make the child more blue, but do not increase the work for the heart.
How are collaterals diagnosed?
When children with single ventricle disorders undergo cardiac catheterisation or MRI scanning investigations it is possible to clearly see the collateral vessels. When there is a large collateral vessel it may be seen during a routine scan (echocardiogram). (See Cardiac tests above).
How are collaterals treated?
Once collateral vessels have been found the cardiac team will assess if they need closing (occlusion). Small systemic arterial collaterals will normally disappear after the Fontan procedure has been performed. Large systemic arterial collaterals should normally be closed by a catheter procedure as they put strain on the heart and raise the pressure in the lung arteries. The child may be more cyanosed after this, and the Fontan operation may have to be performed earlier.
Large systemic venous collaterals in young children after the Cavo-Pulmonary Connection operation (Stage Two) should be closed by catheter. This will make the child less cyanosed, as more blue blood goes to the lungs, and frequently the Fontan operation can be delayed. Small systemic venous collaterals identified just before the Fontan operation can be ignored.
The Damus Procedure
Children who are born with only one of the chambers (ventricles) needed to pump blood around their body and who may also have a narrowing of the body artery (aorta) may need to have surgery to aid circulation of blood from the heart to the body.
The base of the lung artery (pulmonary artery trunk) is attached to the base of the body artery (aorta) to ensure that all the blood that enters the one functioning pumping chamber will be directed around the body.
To ensure that blood also reaches the lungs a connection (shunt) is made between the body circulation and the lung artery (pulmonary artery).
Dental care and sub-acute bacterial endocarditis
Good dental hygiene is extremely important for children with single ventricle heart conditions. The reason it is even more important for these children is that they are at an increased risk of something called endocarditis (a very serious infection of the inner lining of the heart), which is explained below. Always tell your dentist about your child’s heart condition and any medications he or she takes, especially anticoagulants such as Warfarin or Aspirin.
Take your child to see the dentist as soon as their teeth start to appear, and visit regularly, as often as your dentist recommends.
Ask your dentist about fluoride varnish – all children over three years should have this applied to their teeth. If younger children are at particular risk of tooth decay the dentist may apply it to their teeth.
NHS dental treatment is free for children under 18 or under 19 years and in qualifying full-time education.
What is infective endocarditis?
Infective endocarditis is an infection of the lining of the heart that often involves the heart valves. It is a very rare but serious condition.
Why are children and adults with congenital heart disease at risk of infective endocarditis?
If you have congenital heart disease you have malformed parts in your heart, you may also have areas of the heart where operations have created scars. Infections in your mouth or on your skin, streptococcal infections, that normally whizz around your body have somewhere to latch on to creating an infection in the heart.
Why might this affect dental treatment?
Dental procedures which cause bleeding, such as having a tooth extracted, may increase the chances of bacteria entering your bloodstream. However, everyday activities such as brushing your teeth or chewing food can have the same effect over time.
The risk of infective endocarditis developing from either of these routes is very low. However, as it is such a serious condition, your dentist may consider whether any additional precautions are needed for your dental treatment.
Can I reduce the risk of infective endocarditis?
You can reduce the risk by:
- Looking after your or your child’s oral health.
- Cleaning teeth regularly and carefully using fluoride toothpaste.
- Having regular dental check-ups.
- Cutting down on sugary snacks and drinks.
- Not smoking.
- Cutting down the amount of alcohol you drink.
- Taking care of your skin.
- Regularly washing skin with soap and water and wash any cuts or grazes carefully to prevent them becoming infected.
- Avoiding non-medical procedures that involve piercing the skin, including body piercing and tattooing.
Dental treatment, antibiotics and endocarditis
The National Institute for Health and Care Excellence (NICE) no longer recommends that all patients with congenital heart disease should be given antibiotics before dental procedures.
Your dentist will talk with you about the potential benefits and risks of antibiotics and explain why antibiotics are not usually recommended to prevent infective endocarditis.
Most people at increased risk of infective endocarditis will not need antibiotics when they have dental treatment. However, a small number may need to be further assessed.
If this applies to you or your child, your dentist will contact other healthcare professionals involved in your or your child’s care to decide whether you should be offered antibiotics. You will then have the opportunity to discuss whether this is right for you or your child.
LHM would recommend that parents of children and adults with complex heart conditions directly ask your cardiology teams to provide you with a letter to your dentist to say whether or not your child would need antibiotics.
Symptoms of infective endocarditis
You should contact your GP as soon as possible if you notice any of the following symptoms, particularly if they occur together as a flu-like illness:
- A high temperature (fever) of 38oC or above.
- Sweats or chills, especially at night.
- Breathlessness, especially during physical activity.
- Weight loss.
- Tiredness (fatigue).
- Muscle, joint or back pain (unrelated to recent physical activity).
These symptoms are more likely to be caused by a less serious type of infection. However, your doctor will want to investigate. Make sure that you tell them about any recent dental treatment.
Do cardiac medications have any impact on dental care?
Most children with single ventricle heart conditions take anticoagulants such as Warfarin or Aspirin. As these medications make it more difficult for blood to clot, some dental procedures, such as having a tooth removed, could cause more bleeding than in another child.
Remind your dentist about these medications before any dental treatment begins.
He or she might ask for your child to have an extra blood test (INR) the day before the procedure. If you have a home testing kit (CoaguChek machine), it would be really helpful to your dentist if you can take an INR reading on the morning of the procedure.
Planning dental procedures early in the morning is sensible, so that you can easily get help if any complications such as unexpected bleeding happen later in the day.
The NHS National Patient Safety Agency states that an INR of four or less can be safely managed in a standard dental setting. Your dentist will know what extra precautions are needed (for example, special packing or extra stitches if a tooth is taken out).
Your dentist will advise you how to care for your child’s mouth after any treatment. The advice will cover areas such as resting, being very careful as the blood clot forms, and what to do if bleeding starts again. Regular Paracetamol may be advised as a form of pain relief. Unless you are told otherwise, avoid taking medicines like Ibuprofen or Aspirin at the same time as Warfarin
ECMO or ECLS (Extracorporeal Membrane Oxygenation or Extracorporeal Life Support)
Extracorporeal Membrane Oxygenation or Extracorporeal Life Support
Babies and children with congenital heart conditions sometimes have periods of time when they have difficulty pumping enough oxygen-filled blood around their body. This may be because their heart is failing as they await surgery or in the period after an operation when their heart is tired. If doctors feel that a period of added support for the heart will aid recovery they may suggest ECMO.
The ECMO machine is similar to the heart-lung bypass machine used for open heart surgery, although often smaller. Extracorporeal means ‘outside the body’, and a membrane oxygenator is a piece of equipment which delivers oxygen into your child’s blood.
Therefore, ECMO is the use of an artificial lung (membrane) located outside the body (extracorporeal) that puts oxygen into the blood (oxygenation) and continuously pumps this blood into and around the body.
Most congenital heart units are able to offer ECMO for cardiac patients but occasionally a child will be transferred to another cardiac team for the specialised care.
The Fontan Procedure (Stage Three) for all single ventricle conditions or completion of the Cavo-Pulmonary Connection
The final stage of surgery will be performed as the child starts to show that they need more blood flow to the lungs. They may become more breathless on exercise or their growth may slow down. For some children this will occur before they start school. Others may be able to wait a little longer. For more information see the LHM booklet The Fontan.
The Fontan procedure aims to separate the blue (deoxygenated) blood supply and the red (oxygenated) blood supply. Although this does not make the heart function normal, it does allow the children to grow and enjoy more physical activity. The procedure can be performed in two ways.
External Fontan or External Conduit
This operation is done by attaching a tube of a special plastic (a conduit of Gore-Tex) from the lower body vein (inferior vena cava) to the base of the lung artery (pulmonary artery), diverting blue (deoxygenated) blood away from the heart straight to the lungs.
A hole (fenestration) may be created between the tube and the right collecting chamber (right atrium). As with the Internal Fontan (see below) there can be a rise in pressure in the lung arteries after surgery and the hole acts as a pressure valve.
Children may be in hospital for some weeks after the third operation as it is important to give them time to adjust to their new circulation.
This is done by creating a wall (baffle) in the right collecting chamber (right atrium) and then attaching the chamber to the base of the lung artery (pulmonary artery). This may have been partially completed at stage two, the Hemi-Fontan.
All the returning blue (deoxygenated) blood will now be flowing to the lungs, without a pump behind it. This causes an increase in pressure within the lung blood vessels, so, to aid circulation, a small hole (fenestration) may be created in the wall (baffle). This acts as a pressure release valve whilst the child’s body adjusts to the new circulation.
Many families who have a child with congenital heart disease ask why their child was born with the condition. In some cases the malformation will have occurred because of a genetic problem that has affected the heart as it formed in the womb.
When a new house is built the architect draws up a plan of what the house will look like and how it is going to be built.
When a new child is being created, information is drawn from the mother and the father to make a plan of how the child will look and how its body will be put together to work.
A genetic blueprint
Every person in the world has a genetic blueprint of their own. The blueprint is stored in every cell in their body and holds the information required to help the body grow, develop and work properly. The information is made up of lots of messages which we call genes. We have about 30,000 genes in each cell of our body. Different genes have different messages that are responsible for instructing our body to do specific things. For instance, genes determine the colour of our hair or eyes or how cells work in different organs, for example, the liver, heart or lungs. It is our very own information computer.
The genes are stored in coils and split into chromosomes. Humans have 23 pairs of chromosomes, so 46 in total. 23 chromosomes (one of each pair) come from the mother and the other 23 from the father. They are transferred in the egg and the sperm that make a child.
The picture below shows what the chromosomes look like – if you look at the last set of chromosomes in this picture you will see that they are labelled X and Y. These are the chromosomes that decide if you are male or female. The chromosomes below must come from a man because there is an X and a Y chromosome. A woman has two X chromosomes.
Genetics and heart disease
Some congenital heart conditions are linked to a genetic disorder such as Down’s syndrome or 22q Deletion. These disorders are caused when one of the 46 information chromosomes is malformed. As the baby grows in the womb, the genetic malformation will cause a particular part of the heart to develop incorrectly. In some cases the genetic condition can be detected before birth.
Geneticists (genetics doctors) are always looking for genetic causes for congenital conditions; however, there are many heart conditions that do not have a specific genetic cause. Many of the single ventricle heart conditions fall into this group.
There may be many factors, as yet unknown, that cause a baby’s heart to develop abnormally. The problems can occur early in pregnancy as the heart forms or later as it grows.
Congenital heart conditions occur in 1 in 100 pregnancies. If you have previously had a child with a single ventricle heart problem, the risks of it happening again to parents, their other children or the child affected themselves rises to between 5 and 8%. Although the risk is higher, over 90% of future babies will not have a problem with their heart.
This is a commonly used term, which means that the heart is failing to do its job properly. It can occur:
- if a child has a congenital heart defect
- following surgery as the heart is healing
- as the heart muscle grows tired because it has to work too hard.
It means that the heart muscle is unable to pump blood around the body efficiently, often leaving fluid in the body tissues (e.g. the lungs and liver).
Signs and symptoms of heart failure:
Especially when feeding or taking exercise.
Because the heart is working hard, eating and drinking become hard work.
Because all the child’s energy is being used to keep the heart working.
Especially around the eyes, because fluid is not being passed around the body properly.
Small amounts of urine
Because fluid is not moving around the body to the kidneys.
Because the child feels unwell or uncomfortable.
If your child is showing any of the above signs, especially when feeding or taking gentle exercise (e.g. walking), contact your local doctor. It may be that your child has a simple cold but it is always important that someone assesses your child.
If the child is very tired and not completing feeds it may be necessary for them to have a short stay in hospital and some help with feeding. Medications are also given to help the heart function and to help the child pass more urine.
This treatment will give the heart an opportunity to rest and recover. (See Medications). Most children are able to live at home on medication once their condition has stabilised.
The Hybrid Procedure
In the past many newborn babies were not suitable for the Norwood Procedure for Hypoplastic Left Heart Syndrome because they were too small or too sick. Medical teams have been working to develop a procedure that will support a newborn baby’s heart until he or she is big enough to undergo more complex reconstructive operations. This procedure is called the Hybrid Procedure.
For some babies born with a diagnosis of Hypoplastic Left Heart Syndrome, the Norwood Procedure, the first stage of surgery, may not be possible or may have an exceptionally high risk.
The Hybrid Procedure has been developed as a way to help a baby survive until it is strong enough and big enough for the more complex Norwood Procedure.
The aim of the Hybrid Procedure is to allow flow of oxygen-filled red blood (oxygenated blood) to reach the body and to allow used blue blood (deoxygenated blood) to reach the lungs where it can collect oxygen again.
This is done by keeping open the arterial duct and holes that are in the heart whilst the baby is still inside the womb (fetal circulation), at the same time protecting the lung blood vessels so that they can still be used in later surgery. (See Fetal Circulation).
The Hybrid Procedure is performed under a general anaesthetic within the cardiac catheter suite or the operating room or possibly both.
The procedure is performed by both a cardiac surgeon and a cardiologist.
There are three parts to this procedure:
- Small bands are tightened around the left and right lung arteries (pulmonary arteries) to control the flow of blood and pressure in the lungs.
- A mesh of fine metal (stent) is placed in the patent ductus arteriosus (between the pulmonary arteries and the aorta) to keep it open.
- At the same time the hole between the upper collecting chambers (atria) may be made bigger and permanent (atrial septostomy). This may be delayed for about a week.
This procedure has less initial risk than the original Stage One Norwood Procedure but children undergoing the Hybrid Procedure are usually sicker or smaller so their personal risks may be high.
Children who have undergone the Hybrid Procedure will need a more complex operation at Stage Two that will incorporate the reconstructive surgery of the usual Stage One Norwood Procedure as well as the Stage Two Cavo-Pulmonary Connection.
Inserting a stent
Following the ballooning of a blood vessel it may be necessary to insert a stent (a mesh of fine wire in a tube shape) that can be used to keep the blood vessel open after it has been stretched. This is inserted during a cardiac catheterisation.
A very important part of the treatment of complex congenital heart disease is the medical support given to the heart and circulation. This support will be altered as the needs of each child and young adult change as they undergo surgery and grow. Part of the ongoing maintenance of stable heart function will include prescribing medications.
Diuretics are medications that make the kidneys work more efficiently to create urine from the fluid circulating in the blood. The more fluid in the blood, the harder the heart has to work to pump it around the body. It is important to encourage children to continue drinking normally whilst on these medications.
Frusemide (Furosemide)is the most commonly used diuretic; it works well in all age groups.
Amiloride is often used as it keeps the body’s salts (electrolytes) in balance as the child passes out more urine.
Spironolactone is another form of diuretic.
On some occasions these medications are used together.
Medications that strengthen or support the heart’s function
Digoxin is a drug that slows, strengthens and steadies the heart. It is often used in the treatment of heart failure as it makes the heart beat more efficiently.
Captopril, Lisinopril, Ramipril and Enalapril – ACE inhibitors are medications that open up the body’s blood vessels, making it easier for the heart to pump blood through them. This relieves pressure/workload on the heart pumps (ventricles).
Carvedilol is a drug that slows down the resting heart rate and increases the efficiency of the heart muscle.
These are medications that help a heart that is not beating in rhythm. These drugs strengthen the heartbeat and make the beat more regular.
Digoxin is a drug that slows, strengthens and steadies the heart. It is often used in the treatment of heart failure as it makes the heart beat more efficiently.
Amiodarone helps treat heartbeats that are irregular by blocking some defective electrical signals. Avoid eating grapefruit if prescribed this medication because it alters the function of Amiodarone.
Sotalol is prescribed to block irregular electrical messages as they pass through the heart. This steadies the heartbeat.
These are drugs that lengthen the time it takes for the blood to clot. They are used to ensure that the blood flows freely through the tubes and passages that have been created in the heart. For more information see the LHM booklet Living with Anticoagulation.
Aspirin is a gentle anticoagulant that stops blood cells sticking together. It is often the drug of choice in young children.
Warfarin is a medication that slows down the blood’s ability to clot (form scabs). Regular blood tests are required to ensure that the correct dose of Warfarin is given.
Dipyridamole works to interrupt the formation of clots.
Clopidogrel works to hinder the formation of clots. It sometimes replaces Aspirin or can be used in partnership with Aspirin.
Sildenafil works to relax blood vessels so that they widen more easily, making it easier for the heart to push blood through them.
Dipyridamole works to reduce blood pressure by opening up blood vessels. It works especially well in the lungs.
The MCT (Medium Chain Triglycerides) diet is a special diet which is sometimes required by children for a short period of time in hospital after heart or chest surgery or for a short period of time at home. It allows a special type of fat which is not absorbed into the lymph system. If your child requires this diet, the medical staff at your child’s hospital will advise you of the requirement, and the dietitian will help you to understand how to follow the diet at home, and when the diet is finished how to go back to your child’s usual diet. The dietitian will also provide recipes and food supplements as required. For more information and recipe ideas see LHM’s MCT Diet booklet.
This booklet is designed to be used in conjunction with the information and recipes from your dietitian, and aims to provide further recipe ideas, useful food ideas, and to support families at what can be a difficult time by providing practical information.
Please do not follow this diet unless you have been instructed to do so by your child’s cardiology team.
The MCT diet is prescribed when a child or young person is experiencing problems with a build up of fluid within their chest or abdomen.
Everyone has a collection of lymph vessels, similar in look to blood vessels, that carry fat (lymph) around the body. During cardiac surgery, a lymph vessel may get damaged which will cause its contents (lymph fluid) to leak into a chest space. Lymph fluid may also seep from the lymph system into the chest or abdomen due to differences in pressure within the circulation especially after surgery like the Fontan. The collection of lymph fluid in the chest is called a chylothorax.
To help reduce this fluid and allow the lymph vessels to heal, a diet that includes a reduction in fat intake, the MCT diet, will be prescribed. Your child’s medical team may also prescribe a low fluid intake. It sounds quite daunting and does require some extra effort, but it is only for a fairly short period of time. Your child’s dietitian will be able to help you with any concerns you have, and other parents (who you can contact via Little Hearts Matter) may have ideas which worked for their child which could help you. Babies may also be prescribed this diet.
Foods allowed freely on the MCT diet need to have less than 0.2g fat per serving (not per 100g). In general terms, this includes most fruit and vegetables, skimmed milk products, water or fruit juice based drinks, and some foods you have made yourself using MCT oil which is a safe fat.
Your dietitian will send you home with a supply of MCT oil, Liquigen and any calorie supplements or other prescription items you need.
Be very careful when you are reading the labels, as there are lots of different labelling systems, some of which are quite confusing. Some foods are described as ‘low fat’ but are definitely not suitable for this diet. Others (especially diet products) may draw attention to a relatively low amount of saturated fat, but the total fat content may still be too high. Percentages of fat are sometimes quoted, which could be confusing – just ignore percentages.
There is also lots of publicity about ‘good’ fats e.g. Omega 3 fats found in fish such as salmon or in nuts or trans-fats – remember that these are still unlikely to be suitable for an MCT diet – the only ‘good’ fat for this diet is where you have cooked something yourself using MCT oil or Liquigen. (You will be given an initial supply of these products when you leave hospital, and will be given help with ordering further supplies as needed).
In addition, your child will be allowed a set number of daily portions of food which include 1g of fat. This may be referred to as a system of exchanges.
For example, a four-year-old would typically be allowed three exchanges or three grammes of fat per day. These are usually either the protein part of the meal (e.g. a 30 g portion of skinless chicken breast, a 100g portion of plain white fish such as cod) or a treat from a special list of permitted treats (e.g. a Jaffa Cake).
Because they are so high in fat, many foods will have to be excluded completely from the child’s diet for this time, in particular many types of meat (unless given in extremely small portions and counted as an exchange), sausages, normal cheese, nuts, egg yolk or foods containing whole eggs, potato products such as oven chips or waffles, chocolate, most biscuits and cake.
Although this may all seem very daunting, with some imagination, careful shopping and patience in the kitchen, it is possible to create alternatives to many of your child’s favourite foods. For example, they could have a hot chocolate drink made with skimmed milk and chocolate flavouring (liquid flavouring or essence found in the baking section of the supermarket) with marshmallows on top. You might find it helpful to involve your child with the shopping and cooking. Another practical tip is to cook in bulk and freeze portions of food.
Try not to worry about your child’s weight whilst they are on the MCT diet. Although your child will be on a low fat diet, your dietitian will advise about food fortification and use of suitable nutritional supplements to ensure sufficient calorie provision to support weight maintenance and growth during this period.
It may be easier if your child does not eat out or eat at other people’s houses for the duration of the diet unless you are able to take pre-prepared food with you. It will be much safer to provide your child’s meal knowing that it is right for them.
Babies and the MCT diet
Babies may sometimes have to follow the MCT diet. As with children, you must not follow this diet unless it has been prescribed by your child’s cardiologist.
Feeding babies with heart conditions can be challenging, so please contact LHM if you would like any support or guidance if your baby is on the MCT diet.
Sadly breast milk would not be allowed on this diet because its fat content is too high. It is possible to continue to express during the diet so breast feeding can continue after the diet has finished. A special MCT milk will be made up by the dietitians at the hospital, and you will be given instructions on how to make this at home. If you struggle to get your child to accept the new milk, as it may taste different to their usual formula or breast milk, then consult with your dietitian for advice.
As babies with heart conditions have increased energy requirements and may be on high calorie milks and weaning diets prior to starting the MCT diet, the dietitian may ask the GP to prescribe a liquid MCT fat supplement to fortify the MCT milk and low fat purées in order to increase calorie content and promote weight gain. Check the fat content of any bought baby foods very carefully, as even simple foods such as baby rice may have added milk powder, which would make them unsuitable for the MCT diet. As with all of this diet, you need to check that bought foods would be less than 0.2g fat per serving. If you are in a position to make your own baby foods make plain fruit and vegetable purées which can be fortified with your baby’s special MCT milk, Liquigen, or the butter substitute (recipe page 10 of the booklet).
For ideas of recipes download the LHM MCT diet booklet.
Modified Norwood Procedure (Stage One)
This is normally performed within a few days of birth or diagnosis of Hypoplastic Left Heart Syndrome, while the ductus arteriosus (connection which joins the lung artery and the body artery) is being kept open with Prostaglandin therapy. (See Fetal Circulation).
The aims of the first operation are:
- To improve the flow of red blood (oxygenated blood) around the body by attaching the base (trunk) of the lung artery (pulmonary artery) to the body artery (aorta). It may be necessary to enlarge the body artery with a patch.
- To provide a blood flow to the lungs through a passage (shunt), creating a link between the lung artery (pulmonary artery) and the body artery (aorta). The passage is made out of soft plastic (Gore-Tex).
- To create a permanent passage (septectomy) between the collecting chambers (left and right atrium) ensuring that a mix of red (oxygenated) blood and blue (deoxygenated) blood is flowing around the body.
This operation is extremely complicated and holds a high risk (chance of the baby dying). Ask your surgeon about the risk for your child. The baby may need to be in hospital for some weeks following this surgery to ensure that their condition is stable before being sent home.
Modified Norwood Procedure (Norwood with a Sano Shunt)
The reconstruction of the main artery leaving the right side of the heart (pulmonary / aorta vessel) remains as described above; this provides a flow of blood to the body.
The lung (pulmonary) flow of blood is provided by a Gore-Tex tube that leads from the right pumping chamber (right ventricle) to the left lung vessel (pulmonary artery). This connection ensures that blood reaches the lungs where it collects oxygen that is then passed around the body.
This, like the previously described procedure, is an extremely complicated operation and holds a high risk (chance of the baby dying). Ask your surgeon about the risks for your child.
This section explores the sort of complications that can occur before, during or after heart surgery when a child or young adult has a single ventricle heart.
When doctors discuss a new baby’s diagnosis and the treatment path that they plan for them to travel, they also discuss the risks that go hand in hand with a complex heart problem and the treatments available.
Most parents understand that there are major problems when you only have one heart pump.
Here we briefly discuss a broad range of problems that can occur. It is very important that parents, and patients themselves as they get older, talk to their medical team about the risks as not all problems are a risk for each child.
Low oxygen levels
All children with a cyanotic heart condition (blue children) have lower-than-normal oxygen levels. It is safe for them to be moderately low for short periods of time, especially when there is a treatment plan in place and the children are carefully monitored, but if left too low for long periods of time it can affect energy levels and brain function.
There is also a risk of low oxygen levels when a child undergoes surgery or in the post-operative recovery time, especially if the team use the heart-lung bypass machine. Low oxygen levels leading to problems with the brain are known as neurological incidents.
Doctors will explain the risk of low oxygen levels but they will also work to reduce that risk as much as they can.
All children get coughs and colds which need treating in the normal way but post-operatively there is a risk that the chest scar wound both inside the body and on the skin will become infected. The doctors work to prevent this by giving antibiotics but it can still occur after surgery. If the scar is weeping or red a test will be done to identify the type of infection and treatment will begin.
There is also a risk of something called bacterial endocarditis. This is an infection that starts in the mouth and can travel to the heart. For more information about dental care and endocarditis see Dental Care section.
After any operation there is a risk of bleeding. Blood loss will be measured and replacements will be given if the medical staff feel that the loss is compromising blood flow. If the blood pressure remains low for long periods the kidneys are unable to work properly and ultimately blood containing oxygen is unable to reach the brain.
If bleeding occurs between the heart muscle and the outside skin of the heart it can cause problems with the pumping of the heart. If this happens the surgeons may need to remove the blood that has collected there.
Chest drain losses
After chest surgery children and adults have chest drains inserted to ensure that any fluid or blood in the chest can drain away. In some cases the drainage becomes excessive. This could be increased blood loss or because fluid fat is leaking in the chest. If the drainage is excessive, and doctors are unable to keep fluid intake in balance, children can go into shock and collapse.
The heart is responsible for pumping blood around the body. If the heart is not working efficiently, especially around the time of surgery, there is a risk that the blood will clot on areas where surgery has been performed or in pockets of the heart where blood moves slowly. There are also changes to the liver’s function in patients who have a Fontan circulation which makes the risk of clotting greater than normal. There are a number of risks associated with this clotting. The heart’s pumping can be compromised if clots grow within the heart. Small bits of the clot can travel into the lungs, causing problems with breathing, or to the brain where they could cause a stroke. Children and young adults undergoing heart surgery or living with a Fontan circulation are often prescribed anticoagulation medication to reduce the risk of clots. See LHM’s booklet Living with Anticoagulation.
A stroke is a disruption to the circulation of blood to the brain either because of a bleed or because of a blockage, usually a clot. This disruption causes damage to the brain tissue, a condition that is called a stroke. Strokes can take different forms. They can affect mobility, sight, speech and memory, and can cause developmental problems. Medical teams will be working to avoid strokes by making sure that the risk of clots is low, and that the heart is supported to pump well and maintain the oxygen circulating to the brain.
An arrhythmia is a problem with the rate or rhythm of the heartbeat. During an arrhythmia, the heart can beat too fast, too slowly, or with an irregular rhythm. Children with single ventricle hearts have a risk of arrhythmias because of the structure of their heart. The risk is increased after surgery when the circulation has been altered. Arrhythmias can be treated with medications or the use of a pacemaker but often a post-operative arrhythmia will disappear once the heart has recovered from the operation.
A number of these complications can occur routinely around the time of surgery or treatment and so the medical and nursing staff will be watching for them and will intervene with treatment swiftly to help resolve the problems.
Preparation for hospital
Many families contact Little Hearts Matter for advice about how to prepare their children for the later stages of surgery or for a hospital admission for a cardiac catheter. For more information about this see section on Preparation for hospital.
Surgical treatments for right-sided single ventricle conditions
It is often difficult to predict which early procedure will be most helpful in supporting a newborn baby with a complex right-sided single ventricle condition. Some children are born with too much blood flowing to their lungs, others with not enough. In some conditions it is not until after birth that the doctors are able to decide exactly which of the following procedures will be needed by each child.
Many single ventricle conditions cause a restriction of the blood supply to the lungs. As it is essential that blood flows to the lungs to collect oxygen for the body, connections must be created to re-route blood around any blockages within the heart. Surgeons will insert tubes made of either donated heart tissue or Gore-Tex (a specialised plastic) to form connections from the body circulation to the lung circulation. This treatment is often used within the first few weeks of life, as it is a simple solution to the circulation problem. Further more complex surgery will be done as the child grows.
Some children are born with a circulation that causes too much blood flow to the lungs. If the lungs are left with too high a flow, this can damage the lung blood vessels over time. To prevent this damage a band is placed around the base of the lung artery (pulmonary artery). This is usually removed at a later stage of surgery.
Septostomy or Septectomy
Many of the children are born with valves that are malformed so that they block the flow of blood around the heart. It is important to divert blood around the blockages by creating extra channels within the heart. Doctors may choose to create a hole between the two collecting chambers (atria) of the heart either during a cardiac catheterisation or during surgery.
Septectomy is the surgical procedure.
Septostomy is a cardiac catheterisation procedure. (See Cardiac Tests).
The treatment for children with single ventricle heart disease has evolved over the last 20 years. Doctors are now able to offer surgery and medical care that supports the half a heart that each child has to give the children a good, though not perfect, circulation. When one pump is doing the job of two, the heart will gradually tire, leading to increasing heart failure and ultimately the need for new treatment options. Transplantation, with all its challenges, is one of these options.
This following information provides an introduction to transplantation. The aim is to help anyone facing this treatment to gain a greater understanding of the assessment process, surgery and an overview of the risks involved. It will not give you an answer to every question you have about your child. These in-depth questions will be answered by the transplant team during transplant assessment.
Reading this information may be difficult for some parents because transplant is an emotive subject. If you would like to receive support or further information please don’t hesitate to contact the LHM team on 0121 455 8982.
Who needs a transplant?
Transplants are done in children for two main reasons – either the child was born with a healthy heart which developed a problem in pumping blood around the body or the child was born with a heart problem which could not be fixed by regular surgery.
Problems can develop in a previously healthy heart because of a severe viral infection or a genetic defect in the way the heart muscle is programmed to work.
Children born with some serious heart defects, e.g. Hypoplastic Left Heart Syndrome (only one main pumping chamber instead of two), can often benefit for many years from surgery but eventually the valves may leak (back flow), the heart muscle may become worn out or the lung artery pressure may be too high for the blood to be able to flow into the lungs and the circulation gradually fails. If these problems become severe the children may be better treated with a transplant.
The heart transplant story
The history of transplantation can be seen as traumatic and emotional. The bravery of the children who have gone before has allowed for the advances we see today.
The first human heart transplant was undertaken by Professor Christiaan Barnard at Groote Schuur Hospital in Cape Town, South Africa in 1967. He transplanted the heart of Denise Darvall, who was sadly knocked down by a drunk driver just outside the hospital, into a 50-year-old man – Louis Washkansky. The first baby to receive a heart transplant underwent surgery just three days later in New York. Sadly the baby passed away within hours and Washkansky after three weeks.
However, several units around the world were also ready to undertake transplants and so over the next two years over one hundred procedures were performed. Unfortunately most recipients lived for only a short time as the heart was rejected by the immune system. The immune system is very powerful and designed to seek out and destroy things that shouldn’t be in our bodies – mostly these are germs but the immune system also recognises the transplanted heart as “foreign” and tries to reject it. Back in the 1960s and 1970s the drugs available to prevent rejection were not very good and as the results were so poor, transplants were effectively abandoned for a decade until a new and much better drug called Ciclosporin was discovered.
The new era of heart transplantation thus began in 1979 and since then there have been over 100,000 heart transplants in adults and 10,000 in children around the world. In Europe the first successful heart transplant in a baby was performed at Freeman Hospital, Newcastle in 1987 and one year later Great Ormond Street Hospital in London began their transplant programme. These remain the two children’s transplant centres in the UK. Each centre undertakes 15-20 transplants a year and together they have performed more than 600 transplants, making them amongst the biggest children’s heart transplant centres in the world.
How long do heart transplants last for?
Heart transplants are a life-saving treatment but sadly the transplanted heart doesn’t last as long as the natural heart.
The International Society of Heart and Lung Transplantation (www.ishlt.org) keeps a registry of the children’s transplants notified to them from all around the world. Of all the 10,000 children with heart transplants in the ISHLT Registry, half were still alive 15 years after their transplant.
The results from individual centres may be better than the average – for example, transplanted children at the Freeman Hospital live on average for over 20 years. Whilst this extra time to live is to be valued, much research is being undertaken to improve the situation still further.
Why don’t transplants last as long as normal hearts?
There are several reasons why a transplanted heart does not last as long as a normal heart: the children have to survive the transplant operation and the recovery period; despite better medicines, rejection can still occur and may not respond to treatment; additional anti-rejection medication is necessary in the first few months (as rejection is more common then) and so this is when the immune system is at its weakest and serious infections can occur. On average, of ten children undergoing a transplant, eight will still be alive after one year but one or two will have died either at the time of transplant, in the intensive care unit afterwards or because of rejection or infection in that first year.
The medicines we give the children are now much better than the older medicines but they still have side effects that can affect some children:
- Some medicines gradually reduce the function of the kidneys. Usually this doesn’t affect the children but is noticeable on blood tests. For a few, however, many years after transplant, the kidney function may become so poor that kidney dialysis or a kidney transplant becomes necessary.
- As the medicines weaken the immune system, infections can be more frequent and take longer for the children to get over. This is more common in small children as they haven’t yet met many of the germs that older children already have some resistance to.
- Another natural function of the immune system is to destroy cancer cells that the body makes from time to time. It is less efficient at doing this after a transplant and so cancers are more common than in other children. Fortunately most of these cancers can be successfully treated.
Further information on medications after a transplant can be found further down.
However, the main reason why the transplanted heart doesn’t last forever is that over time the coronary arteries (blood vessels that feed blood and oxygen to the heart muscle itself) become blocked and the heart muscle stops working – usually gradually, but occasionally suddenly. This problem, often called chronic rejection, is common to all organ transplants – heart, liver, kidney or lung and none of them last forever. Over the years treatments have improved a little but the main problem hasn’t been solved.
At present the only solution is a re-transplant. A re-transplant cannot be promised, any more than a first-time transplant due to a lack of donors, but if possible it will be undertaken.
In the future we hope that better treatments will become available and that the children who have recently received a heart transplant will benefit from tissue engineering, stem cell treatment or advances in artificial pump technology.
What is the quality of life after a transplant?
After a transplant children are able to do most normal things – play with friends, go to school, have pets, join in sleepovers, travel abroad on holiday and have fun.
There are some things of course that are not normal. The children have to take medicines morning and night to prevent rejection occurring, they need blood tests to check that they are on the right amount of medication – not too much and not too little – and they need clinic check-ups to make sure their heart is working well.
The frequency of check-ups varies – in the beginning it may be every week but as time goes by the visits become less frequent and for some it is just four times a year.
Some children may have difficulty concentrating – this is probably because they were very ill before and around the time of transplant and because of the medications they need afterwards. A small number also experience psychological difficulties. However, most of the children are able to do well at school and take part in lessons, and many have gone on to university. Furthermore, most children can participate in physical exercise in school and at home – they tend to be better at the short-burst activities rather than those that require a lot of stamina (for example, cross country running). Many take part in the annual Transplant Games which help increase confidence and self-esteem and are a great opportunity to have fun and meet up with other transplant families. As the children become adults they can work in most jobs and go on to have children themselves if they wish.
How does a child get on the heart transplant list?
Once a child is showing signs that their heart is failing to do its job properly their medical team will need to decide what treatment options are available to give them a better quality of life for longer.
If they decide that it is time to consider the transplant option they will refer them to one of the two children’s transplant centres in the UK. The centres will then make arrangements for an assessment to be made – this is usually over two to three days as an inpatient when all the previous information known about the child is reviewed and further blood tests and scans are undertaken as needed.
This information is required to see if a transplant is necessary, how quickly it is required and how the risks can be minimised. The assessment gives the transplant team a chance to get to know you and your child and most importantly allows time for you to get as much information about transplant as you want or need.
Once it is decided between you and the transplant team that transplant is the best option then your child will be placed on the transplant list. There are two lists in the UK – urgent and routine. Each has set rules that need to be met but in general terms the urgent list is mainly for children who are too poorly to leave hospital whilst the routine list is for those who can wait at home. Currently, however, very few children on the routine list receive transplants as there are always more children waiting urgently in hospital and not enough donors to go around.
Sadly this means that to have a realistic chance of transplant some children have to wait until they are so poorly they have to be in hospital to get on the urgent list. When a donor heart becomes available it is offered to the first suitable child on the urgent list, taking into consideration their size, blood group and any antibodies they may have against the donor organ, regardless of which hospital they are in.
The transplant team and transplant assessment
When you are sent to a transplant centre for assessment and through all transplant care you will be looked after and treated by the transplant team.
The team is made up of transplant cardiologists and surgeons, specialist nurses, psychologists, play specialists and transplant co-ordinators (who co-ordinate the donation and retrieval of any organs, support the family and generally organise the transplant process).
This team works together to make families feel comfortable, explains the stages of assessment and treatment and, after transplant, co-ordinates ongoing care.
Transplant assessment offers children, young adults and their families an opportunity to seek answers to questions about what transplant means for them. All decisions about transplantation will be taken as a team – doctors, nurses, psychologists and the family.
How long is the wait for a transplant?
As there are not enough donors for all the children most have to wait for their transplant. On average the waiting time is five months and sadly around one in four children die whilst waiting for a transplant.
The graph shows what happens to 100 children listed for transplant in the UK. At time zero 100 children are on the list, by one month 78 are still listed, 22 have received transplants, ten have died but no child’s heart function has recovered. By one year nine are still on the list, 60 have received transplants, 23 have died and eight have recovered. The arrow points to the time (5 months) when half of those listed have had a transplant – i.e. the average wait is five months.
However, for any one particular child the length of time waiting for a transplant varies depending upon their size, blood group and whether or not they have developed antibodies against potential donors (HLA antibodies). Children are not born with HLA antibodies against other people’s organs but can develop them if they have had heart operations in the past, blood transfusions or some types of infections. These are the types of technical issues the transplant assessment looks at and tries to overcome in order to minimise the risks.
How are children kept alive whilst waiting for a transplant?
Keeping the children alive and well whilst they wait for a transplant can be very challenging – especially for children with single ventricle circulations. Some are able to manage with medicines but others need medication given directly into their veins to keep them alive. If these are not enough to help the circulation then the support of a mechanical heart might be needed.
Mechanical hearts or pumps are very good for children with a two ventricle circulation but do not work as well for those with a single ventricle. As with all treatments this type of treatment has complications.
One of the most common pumps used, especially in small children and babies, is the Berlin Heart (see picture). The pump has two pipes (cannulae) that take blood out of the heart, pump the pressure up and then two cannulae to return the blood to the lungs (right heart pump) and body (left heart pump). If the right heart is undamaged only a left heart pump is necessary. The pipes come out from under the rib cage and the main complications are bleeding, infection and blood clots. Clots occur in up to one in three children despite the use of blood thinners and are especially worrying as clots may become loose and travel to the brain causing stroke.
A different type of pump called Heartware is available for some older children and can be implanted inside the chest although a cable still needs to be passed out of the body and attached to the power supply (battery or mains) and controller. This system is good enough for some children to be managed at home. In the future we expect these pumps to become smaller and easier to use.
Can the heart recover?
Not all hearts can recover but some may, for example, if damaged by a virus. Even if the recovery is not complete it may be sufficient to avoid transplant for the time being. Delaying or avoiding transplant altogether is obviously preferable provided the child’s own heart function recovers enough to keep them well and active.
How are we contacted when a heart is available?
Once a child has been accepted for a transplant the transplant team at the transplant hospital will explain the next steps, give parents contact details and keep in touch. It can be a stressful time waiting for a heart to become available so the transplant nurses and co-ordinators will help to support families as much as they can.
When a suitable heart becomes available the transplant team will get in touch if a child has been able to wait for their heart transplant at home. Parents will be contacted on their mobile phone or, occasionally, via a bleeper to ring the transplant hospital. Whilst there is only a four-hour window to remove a heart and transplant it into the patient the transplant team will know of a possible donor some hours before and so make arrangements at that time for the child to come to the hospital in plenty of time.
What about the donor?
Of course without donor families no one could receive a transplant – it is such a bitter-sweet gift as to give a donor heart means that someone in their family has died. However, the donor families often say that the only comfort they get is knowing their loved one has saved lives. Transplant families often wish to thank the donor family and can write a letter to them. The transplant co-ordinator can advise and facilitate this process as it is obviously a difficult letter to write. Occasionally donor and recipient families wish to meet and this may be possible to arrange.
One way everyone can help is to sign up to the NHS Organ Donor Register, tell their families their wishes and encourage their family and friends to do so too – it truly is the greatest gift anyone can give.
The transplant operation
The transplant team usually gets several hours warning of a possible donor. A team is sent to inspect the heart and, if it is suitable, then it is removed and brought to the transplant unit.
There is a four-hour window from taking the heart from the donor to implanting it into the child. The recipient transplant co-ordinator manages the whole process, ensuring the donor and the recipient medical teams work seamlessly together.
The child is taken to the operating theatre before the donor heart arrives as it takes some time to remove the old heart – the main veins and arteries are cut through and the old heart removed with the child being kept alive with the heart-lung machine as for any other heart operation.
Once the donor heart arrives it is connected by stitching together the veins that bring blood back from the body and lungs, and the main arteries that take blood to the lungs and body (see diagram).
Although children with single ventricle circulations often have very different anatomy the surgeons are very skilled and with proper planning can connect in the new heart. The old heart is sent for pathological examination. The transplant operation takes several hours to complete. Afterwards the child is brought back to the intensive care unit to recover.
Recovery, with the exception of the additional transplant medications, is very similar to any child recovering from an open heart operation. The period in the intensive care unit is usually a few days to weeks, depending on how poorly the child was prior to the transplant.
Once the child has recovered sufficiently they are able to go to the heart ward. To prevent infections, visiting by those other than immediate family is restricted. On the ward whilst the child is recovering a teaching programme is put in place so that parents/carers gain confidence in managing the transplant medicines, and learn how to look out for rejection and the other complications that can occur.
What happens after going home?
Once the child has recovered and the family are familiar with the transplant system then they can go home. It can still take time to fully recover and most children stay off school until three months after the transplant. The number of medicines is often quite large initially but after three months this is usually reduced and may be less than the number of medicines the children took before transplant. As rejection is possible any time after transplant these medicines need to be taken for life.
Clinic visits are frequent at the heart transplant unit at first. The heart is monitored by blood tests, scans and sometimes by taking a small piece of the heart muscle away at a cardiac biopsy (similar to a cardiac catheter test) usually under an anaesthetic. There is also an annual “MOT” visit where more tests may be undertaken. Once the recovery is established there will be shared care between the transplant unit and the local cardiac team.
Life after transplant is very different for children who have never been ill before but is not so different for children born with a serious heart problem who are used to taking medications and hospital check-ups. It brings its own challenges and rewards but most children have an active, fulfilling life.
Commonly used post-transplant medications
All children will be on some medications (usually at least twice a day) following cardiac transplant with the medication tailored to the individual. It is important that doses of medication, in particular immunosuppressants, are not missed. Although this can seem arduous at first, families and children soon get into a routine. Many will have been taking regular medication prior to the transplant and taking the medication becomes as much a part of everyday life as teeth brushing.
When a heart is transplanted into a body the immediate reaction of that body is to reject it, just like the body would fight an infection. Of course it is important that the body gradually accepts the new heart and stops fighting it. Medications called immunosuppressants are given twice a day for life to stop the body rejecting the heart.
There are a variety of different medications that work in different ways to reduce rejection. The transplant centres guide the immunosuppression treatment and the choice of drugs depends upon the individual needs of the child and whether they develop any side effects to the medicines. There is more than one drug in each category and so, even if a child reacts to one medicine, another can be chosen.
These form the backbone of the immune suppression regime and most children will be on one calcineurin inhibitor lifelong following heart transplant (usually given twice daily). The two drugs commonly used are Tacrolimus and Ciclosporine. It is vital that doses are not missed. If the medication cannot be taken (for example, during a vomiting illness) medical advice needs to be urgently sought from the transplant centre. The levels of the drugs are monitored by regular blood tests.
Anti cell proliferation medications
These are often used in addition to calcineurin inhibitors. There are three commonly used (although not together) drugs. They are Mycophenolate Mofetil, Azathioprine and Rapamycin. The choice depends upon the needs of a particular child, for example, if kidney function is a concern then Rapamycin might be chosen.
Steroids are given at the time of transplant and for a few days afterwards. Sometimes they are needed for longer. The transplant doctors will advise if this is the case.
Following a heart transplant, children’s immune systems are suppressed by the medications and they are therefore more susceptible to infections. Antibiotics are usually given for a period of three to six months following the transplant as the immune system is at its weakest then, to reduce the risk of infection. These may include Cotrimoxazole and Acyclovir. Actual infections are of course treated by specific antibiotics to defeat the germ.
Blood pressure medications
Children often have high blood pressure soon after transplant, most commonly because they overcompensate as they now have good heart function having been used to poor heart function in the past. The high blood pressure then goes away but usually returns some years later due to the effect of the immunosuppressant on the kidney function which then drives the rise in blood pressure. High blood pressure is usually readily treated with medications, for example, Captopril, Enalapril or Amlodipine.
Medicines to remove excess fluid (for example, Furosemide) are often used early post-transplant, however, in most cases diuretics can be stopped in the months following transplant as the new heart’s function normalises.
Statins have become a standard part of management following heart transplant. Most people know of them for their cholesterol lowering effect. However, whilst this does occur in transplant recipients, they have been shown to help the heart last for a longer period of time. Whilst the reason for this is unclear they probably reduce inflammation in the blood vessels and act as a ‘weak’ immunosuppressant.
Heart transplantation – A guide for families, is available to download as a pdf booklet and also includes a personal account of Oliver’s transplant journey.
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