Congenital heart disease

Congenital heart disease is a general term for a group of birth defects that affect the heart.

Congenital heart disease can take more than 30 different forms, because there are over 30 different types of heart defect. The two main types are:

• cyanotic heart disease
• acyanotic heart disease

Cyanotic heart disease is a condition where problems with the heart mean there isn't enough oxygen in the blood.

Babies born with it often have a blue tinge on parts of the body such as the fingers, toes and lips, because they aren't getting enough oxygen.

They may also have these symptoms:

• breathlessness
• chest pain
• palpitations
• fainting
• fatigue

Acyanotic heart disease is a type of congenital heart disease where the blood carries enough oxygen, but it's pumped around the body in an abnormal way.

A baby born with acyanotic heart disease may show no obvious symptoms. Over time, though, the condition can cause health problems.

In this group of conditions, blood pressure can rise a great deal. The heart has to work much harder and comes under more strain. This can weaken the heart and raises the risk of heart failure, where the heart muscle can't pump blood around the body efficiently.

The blood pressure in the lungs is also often too high. This is called pulmonary hypertension, and it can damage the lungs and cause symptoms such as:

• breathlessness
• fatigue
• dizziness
• fainting

Congenital heart disease is the most common type of birth defect. About 1 in 180 babies are born with it.

Some babies with congenital heart disease need surgery straight after birth. Many others will probably need surgery or medicine at some point during childhood.

The condition can sometimes develop alongside certain genetic conditions, such as Down's syndrome. An infection during pregnancy, such as rubella, can also cause it. But in many cases of congenital heart disease, no clear cause is found.

The outlook for congenital heart disease varies with the type and severity of the heart defect.

Research into the causes, along with better treatments, means that 80% of children with congenital heart disease will survive into adulthood.

This brings new challenges for health services, because some of these adults have complex health needs and require specialised care for life. In response, the Department of Health has recommended setting up specialised centres to care for adults with congenital heart disease.

In adults, the condition is sometimes known as 'grown-up congenital heart disease' (GUCH) or Adult Congenital Heart Disease (ACHD).

Cyanotic heart disease can cause several symptoms:

• a blue tinge to the lips, fingers and toes (cyanosis)
• palpitations
• fainting
• fatigue
• chest pains
• breathing problems

Children with cyanotic heart disease have lower levels of oxygen in their blood. This is known as hypoxia.

Sometimes their oxygen levels can fall even further, and that can bring on other symptoms such as anxiety, confusion or disorientation.

Acyanotic heart disease can cause these symptoms:

• severe tiredness
• palpitations
• chest pain
• shortness of breath (particularly during activities such as climbing the stairs)

Some symptoms show up in both cyanotic and acyanotic heart disease. These include:

• poor appetite and feeding difficulties
• sweating, particularly when a baby is feeding
• delayed growth

Children with acyanotic heart disease are usually underweight. Children with cyanotic heart disease are usually underweight and also small for their age.

To understand how congenital heart disease can affect your child's heart and general health, it helps to first understand how a healthy heart works. You can find out how your heart works on the British Heart Foundation website.

Congenital heart disease develops when abnormalities in the heart's structure stop it from working as it should.

The 2 main types are:

• cyanotic heart disease
• acyanotic heart disease

Ventricular septal defect (VSD) is a very common cause of acyanotic heart disease. In a VSD, there is a hole between the left and right ventricle.

Blood pressure is higher on the left-hand side of the heart, so blood gets pushed through the hole and into the right ventricle.

The heart then has to work harder to pump this extra blood out of the right ventricle, and that can strain it. The extra blood, and the pressure it carries, can also raise the blood pressure in the lungs and damage them (pulmonary hypertension).

In pulmonary stenosis, the pulmonary valve on the right side of the heart is unusually narrow. This means the heart has to work harder to pump blood into the lungs, and that extra effort can put a strain on the heart.

In aortic stenosis, the aortic valve on the left side of the heart is narrower than it should be, so the heart has to work harder to push blood through it. The aortic valve is the main route that carries oxygen-rich blood out to the body. When it's narrowed, the body's oxygen supply can drop, and that can cause breathlessness and dizziness.

Patent ductus ateriosus (PDA) is a duct, or passage, in the heart that is meant to close shortly after birth.

While a baby is in the womb, the heart has no need to send blood to the lungs, because the baby gets all the oxygen it needs from the mother through the placenta. So the ductus ateriosus works as a bypass, which means blood can flow back into the heart without going through the lungs.

Shortly after birth, as the baby begins to breathe normally, the duct should close. In PDA, though, the duct doesn't close completely. Some oxygen-rich blood that is meant to be pumped away from the lungs leaks back through the duct and into the lungs again.

This puts strain on the heart and the lungs, because both have to work harder to make up for the problems the duct causes.

Tetralogy of Fallot (TOF) is the most common cause of cyanotic heart disease. It isn't one heart defect but a combination of four different ones. Tetralogy is a Greek word that means 'four-fold', and Fallot is the name of the doctor who first identified the condition.

In TOF, four defects affect the heart:

• A hole between the left and right ventricle (Ventricular Septal Defect).
• A narrowing of the pulmonary valve (pulmonary stenosis).
• The muscles of the right ventricle are unusually thick (right ventricular hypertrophy).
• The aorta sits over both the left and right ventricles, instead of just the left ventricle as in a normal heart (overriding aorta).

Because of this complex set of heart defects, oxygen-rich blood and oxygen-low blood become mixed. So blood with lower-than-normal oxygen content is pumped around the body.

The body's cells and tissue don't get enough oxygen, and the child develops the symptoms of cyanotic heart disease.

You can find out more about TOF on the British Heart Foundation website.

Transposition of the great arteries (TGA) is a major cause of cyanotic heart disease.

In TGA, the pulmonary artery is attached to the left side of the heart, and the aorta is attached to the right side. So blood that is low in oxygen, which should go to the lungs, gets pumped around the body instead. This causes the symptoms of cyanotic heart disease.

You can find out more about TGA on the British Heart Foundation website.

In many cases of congenital heart disease, doctors can't find a clear reason why a baby is born with a defective heart. Some risk factors are known, though, and they are listed below.

Women with diabetes are five times more likely to give birth to a baby with congenital heart disease than women who don't have diabetes. It's estimated that out of every 100 pregnancies in women with diabetes, three to four will end with a baby born with a heart defect.

The higher risk is thought to come from high levels of insulin in the blood, which may interfere with the development of the foetus.

Rubella (also called German measles) is a viral infection, and it is a major risk factor for congenital heart disease when a woman catches it in early pregnancy.

If a woman gets rubella during the first 12 weeks of pregnancy, there is an 80% chance that her baby will be born with a birth defect, such as congenital heart disease.

If a mother drinks more than the recommended daily amount of alcohol during pregnancy, her baby has a higher risk of being born with congenital heart disease.

It's best to avoid alcohol altogether while you're pregnant. However, no adult should drink more than 2-3 units a day.

Several genetic conditions can cause congenital heart disease. These are health conditions a baby inherits from one or both parents.

Down's syndrome is the best known of them. Children born with it have a range of disabilities because of a genetic abnormality. Approximately half of children with Down's syndrome will have congenital heart disease.

Other genetic conditions linked to congenital heart disease include:

• Turner syndrome
• Noonan syndrome

More and more cases of congenital heart disease are now found before a baby is born, by doing a foetal echocardiograph.

This is a type of ultrasound scan that has been specially made to build a picture of the unborn baby's heart. It should be done during routine antenatal examinations, usually sometime between the 18th and 20th week of pregnancy.

A foetal echocardiography can't always pick up a heart defect, particularly a mild one.

If your baby is born with cyanotic heart disease, doctors can usually diagnose it quickly and with confidence, because the skin has a distinctive blue colour.

Acyanotic heart disease is different. If your baby is born with it, the symptoms may not become clear for several months, or even years, after birth.

Possible signs that your child may have a cyanotic heart disease include:

• problems feeding
• slow growth
• shortness of breath after exercising
• tiredness after exercising
• swelling of their hands, feet and ankles

You should contact your doctor if your child has any of these symptoms. Further tests can confirm or rule out congenital heart disease.

An echocardiogram may be used to check your child's heart. Sometimes there are underlying problems with the heart that were missed during a foetal echocardiogram, and these can be picked up as a child grows up.

You can find out more about an echocardiogram on the British Heart Foundation website.

An electrocardiogram (ECG) is a test that measures the electrical activity of the child's heart. Electrodes are placed on the skin across the chest, arms and legs, and then connected to an ECG machine. The machine analyses the electrical signals the heart produces to assess the heart rhythm.

Find out more about an ECG on the British Heart Foundation website

A chest X-ray of the heart and lungs can show whether there's anything abnormal in the lungs, or whether the heart is larger than normal. Either one can be a sign of congenital heart disease.

You can find out more about a chest X-ray on the British Heart Foundation website.

Pulse oximetry is a simple test that measures how much oxygen is in the blood.

The doctor places a small sensor on your child's fingertip, ear or toe. The sensor sends out light waves, and a computer connected to it checks how much of that light is absorbed. It then gives you a reading as a percentage.

In a healthy person, the reading should be 94% or above. Children with cyanotic heart defects often have readings below this.

Cardiac catheterisation is a useful way for doctors to find out exactly how blood is pumping through your child's heart.

During the procedure, the doctor inserts a small, flexible tube called a catheter into one of your child's blood vessels, usually in the groin or arm. The tube is then moved up into the heart, and X-rays are used to help guide it.

A contrast dye that shows up on X-rays can be injected into the tube. The medical staff watch the dye as it moves through the heart, and this lets them see how well each chamber is working. They can also take blood pressure readings in different parts of the heart. Both of these help with diagnosis and with planning treatment.

Cardiac catheterisation is usually done under a local anaesthetic, and it is a relatively painless procedure.

Doctors can use several different surgical techniques to treat congenital heart disease, and some of them are explained below.

A thin tube called a catheter, much like the one used during diagnosis, is passed into the heart. Doctors then pass tools down the catheter to repair the heart defects.

The advantage of this type of surgery is that it's minimally invasive. This means your child will not need open heart surgery.

When a child has a more serious type of congenital heart disease, the doctors may need to operate directly on the heart.

In open heart surgery, the surgeon may stop the heart for a time and use a machine to pump blood around your child's body (this is called a bypass machine). The surgeon makes an incision in your child's chest. Through it, the heart defects can be repaired, or damaged parts of the heart, such as the valves, can be replaced.

In more serious cases of congenital heart disease, the heart may be too damaged, and the child too ill, for corrective surgery to be done safely. When that happens, the child's heart may have to be replaced with a donated heart.

If your child needs a heart transplant, their details will be placed on the National Transplant Database (NTD). Depending on the condition of your child's heart, they may need to stay in hospital to support the heart's function until a donated heart becomes available. Machines such as the ventricle assist device (VAD) act like an external mechanical heart and can help pump blood around the body.

Priority for heart transplants is based on clinical need, not on who came first. If your child is in a very unstable condition, they will be given priority, while more stable children will have to wait longer.

Once a donated heart of the right size and blood group becomes available, the transplant team will contact you and ask you to go to the transplant unit as soon as possible. You may be given a bleeper so they can reach you quickly.

You can find out more about heart transplantation on the British Heart Foundation website.

If your child is diagnosed with a ventricular septal defect (VSD) or an atrial septal defect (ASD), the treatment the doctor recommends will depend on the size of the defect.

If the defect is small, the doctor may suggest 'watchful waiting'. Your child gets no treatment straight away, but their health is checked carefully over time. This is because 90% of small defects close by themselves as the child grows older.

For mild to medium-sized defects, it may be possible to seal the hole using a catheter. The catheter is guided to the site of the hole, and a specially made mesh is passed through it to close the defect.

For medium to large defects, open-heart surgery may be needed. In this operation, a patch is stitched directly over the defect.

If your child is diagnosed with stenosis (a narrowing of one of their valves), the treatment the doctor recommends will depend on how severe the narrowing is and whether your child has symptoms.

In mild cases, the doctor may suggest "watchful waiting", which means keeping an eye on the condition over time. Medicine that lowers blood pressure may also be recommended, to reduce the strain on your child's heart and lungs.

In more serious cases of stenosis, a catheter can be used to widen the valve. A small balloon is passed up through the catheter and then inflated to widen the affected valve. This is called a balloon angioplasty. Once the valve has been widened, the balloon is removed. Sometimes a metal coil (stent) is used to keep the valve open.

In more serious cases, it's sometimes necessary to replace the valve with open heart surgery. Replacement valves can come from human donors, or they can be made from artificial materials such as titanium, or taken from pigs and modified for human use. Pigs are used because their hearts are the most similar to the human heart.

Some people are too ill or weak to withstand open heart surgery. For them, a catheter approach can be used. The catheter is passed through a blood vessel in the groin and up into the heart, and a replacement valve is passed through it and into position.

Many cases of patent ductus ateriosus (PDA) can be treated soon after birth with medicine. Two medicines, indomethacin and a special type of ibuprofen, have been shown to work well in helping the duct close. This duct is what causes PDA.

If the PDA doesn't respond to medicine, doctors can use a catheter to seal the duct with a metal coil or plug.

Babies born with Tetralogy of Fallot (TOF) who have severe breathlessness may need emergency surgery, such as a Blalock-Taussig shunt (a BT shunt).

In a BT shunt, an artery is diverted (or shunted) towards the lungs, so the baby has a supply of oxygen-rich blood. Further open-heart surgery is then recommended once the baby is old enough to cope with the after-effects of the operation. During this open-heart surgery, the defect between the ventricles is sealed and the pulmonary valve is widened.

Transposition of the great arteries (TGA) needs open-heart surgery, and this is usually done soon after your baby is born.

Doctors usually treat TGA with a technique called an arterial switch. In this operation, the affected arteries are cut and then reattached in their correct position on the other side of the heart.

About 80% of children with congenital heart disease will survive into adulthood. Living as an adult with congenital heart disease brings a new set of challenges, and some adults will need specialised care.

Routine medical procedures, such as giving birth or having a general anaesthetic, need close supervision by specialist staff who have experience in treating adults with congenital heart disease. There is also a risk that earlier heart surgery, such as the insertion of a replacement valve, will fail and that more surgery will be needed.

Because of this, older teenagers are advised to register with a specialised adult congenital heart disease clinic. The clinic can give you regular check-ups and assessments, work with other specialised medical services when they are needed, and offer ongoing support and advice.

Your doctor or treatment team can tell you more about services in your area for adults with congenital heart disease.

Many children with congenital heart disease have delays in their development. They may take longer to reach certain stages, such as walking or talking.

Some children with congenital heart disease also have learning difficulties, and they need specialised educational and psychological help.

If your child has congenital heart disease, your local educational authority should draw up an individual education plan (IEP). The IEP assesses your child's current and future needs. It also gives access to any specialised services your child needs, such as speech and language therapy or an educational psychologist.

The IEP will also take into account what level of physical activity is safe for your child. Children with congenital heart disease should be encouraged to be as active as possible, but certain activities, such as contact sports, may have to be avoided.

Both children and adults with congenital heart disease have a higher risk of developing endocarditis. This is an infection of the lining of the heart. If it isn't treated, it can be life-threatening, because it damages the valves of the heart.

The symptoms of endocarditis include:

• fever
• chills
• sweating (including night sweats)
• muscular aches and pains
• chest pain
• coughs
• weakness and fatigue
• headache
• shortness of breath

Endocarditis needs to be treated with injections of antibiotics (intravenous antibiotics), and that means a hospital stay of several weeks.

The infection usually starts somewhere else in the body, such as on the skin or the gums, and then spreads through the blood into the heart. Gum disease can lead to endocarditis, so if you have congenital heart disease, it's very important to keep your mouth and teeth very clean and well cared for.

Doctors also usually recommend that you avoid any cosmetic procedure that pierces the skin, such as tattoos or body piercings.