Congenital heart disease

Congenital heart disease


Congenital heart disease is a general term for a range of birth defects that affect the normal workings of the heart.

The term “congenital” means the condition is present at birth.

Congenital heart disease is one of the most common types of birth defect, affecting up to 9 in every 1,000 babies born in the UK.

Why it happens

In most cases, no obvious cause of congenital heart disease is identified. However, some things are known to increase the risk of the condition, including:

  • Down’s syndrome  a genetic disorder that affects a baby’s normal physical development and causes learning difficulties
  • the mother having certain infections, such as rubella, during pregnancy
  • the mother having poorly controlled type 1 diabetes or type 2 diabetes
  • other chromosome defects, where genes may be altered from normal and can be inherited 

Read more about the causes of congenital heart disease and preventing congenital heart disease.

Many cases of congenital heart disease are diagnosed before a baby is born during an ultrasound scan in pregnancy. However, it’s not always possible to detect congenital heart defects in this way.

Signs and symptoms

Congenital heart disease can have a number of symptoms, including:

  • rapid heartbeat
  • rapid breathing
  • excessive sweating
  • extreme tiredness and fatigue
  • a blue tinge to the skin (cyanosis)
  • tiredness and rapid breathing when a baby is feeding 

These problems are sometimes noticeable soon after birth, although mild defects may not cause any problems until later in life.

Read more about the symptoms of congenital heart disease and diagnosing congenital heart disease.

Types of congenital heart disease

There are many types of congenital heart disease and they sometimes occur in combination. Some of the more common defects include:

  • septal defects  where there’s a hole between two of the heart’s chambers (commonly referred to as a “hole in the heart”)
  • coarctation of the aorta  where the main large artery of the body, called the aorta, is narrower than normal
  • pulmonary valve stenosis  where the pulmonary valve, which controls the flow of blood out of the lower right chamber of the heart to the lungs, is narrower than normal
  • transposition of the great arteries  where the pulmonary and aortic valves and the arteries they’re connected to have swapped positions

Read more about the types of congenital heart disease.

Treating congenital heart disease

Treatment for congenital heart disease usually depends on the defect you or your child has.

Mild defects, such as holes in the heart, often don’t need to be treated, as they may improve on their own and may not cause any further problems.

Surgery or interventional procedures are usually required if the defect is significant and causing problems. Modern surgical techniques can often restore most or all of the heart’s normal function, and nowadays about 80% of children with congenital heart disease will survive into adulthood.

However, people with congenital heart disease often need treatment throughout their life and therefore require specialist review during childhood and adulthood. This is because people with complex heart problems can develop further problems with their heart rhythm or valves over time.

Most surgery and interventional procedures aren’t considered to be a cure. The affected person’s ability to exercise may be limited, which can progress over time and may lead to the need for further surgery or intervention.

Some people with more complex congenital heart disease may not have a normal life span. It’s important that a person with heart disease and their parents or carers discuss these issues with their specialist medical team.

Read more about treating congenital heart disease and the complications of congenital heart disease.

Types of congenital heart disease

Congenital heart disease refers to a range of possible heart defects.

The following defects are described below:

Aortic valve stenosis

Aortic valve stenosis is an uncommon and serious type of congenital heart defect. It accounts for around 5% of cases of congenital heart disease.

In aortic valve stenosis, the aortic valve that controls the flow of blood out of the main pumping chamber of the heart (the left ventricle) to the body’s main artery (the aorta) is narrowed. This affects the flow of oxygen-rich blood away from the heart, towards the rest of the body, and may result in the left ventricle muscle thickening because the pump has to work harder.

Coarctation of the aorta

Coarctation of the aorta (CoA) is where the main artery (the aorta) has a narrowing, which means that less blood can flow through it.

CoA accounts for around 10% of cases of congenital heart disease. It can occur by itself or in combination with other types of heart defects  most commonly a ventricular septal defect or a type of defect known as a patent ductus arteriosus (see below).

In around half of all cases, the narrowing can be severe and will require treatment shortly after birth.

Ebstein’s anomaly

Ebstein’s anomaly is where the valve on the right side of the heart (the tricuspid valve), which separates the right atrium and right ventricle, doesn’t develop properly. This means blood can flow the wrong way within the heart, and the right ventricle may be smaller and less effective than normal.

Ebstein’s anomaly can occur on its own, but it often occurs with an atrial septal defect (see below). It’s estimated that Ebstein’s anomaly accounts for less than 1% of congenital heart disease cases.

Patent ductus arteriosus

Patent ductus arteriosus (PDA) is a rare type of congenital heart disease, affecting around 5 in every 100,000 babies.

As a baby develops in the womb, a blood vessel called the ductus arteriosus connects the pulmonary artery directly to the aorta. The ductus arteriosus diverts blood away from the lung (which isn’t working normally before birth) to the aorta.

A patent ductus arteriosus is where this connection doesn’t close after birth as it’s supposed to. This means that extra blood is pumped into the lungs, forcing the heart and lungs to work harder.

Pulmonary valve stenosis

Pulmonary valve stenosis is a defect where the pulmonary valve, which controls the flow of blood out of the right heart pumping chamber (the right ventricle) to the lungs, is narrower than normal. This means the right heart pump has to work harder to push blood through the narrowed valve to get to the lungs.

Pulmonary valve stenosis accounts for around 10% of cases of congenital heart disease.

Septal defects

A septal defect is where there’s an abnormality in the wall (septum) between the main chambers of the heart. The two main types of septal defect are outlined below.

Atrial septal defects

An atrial septal defect (ASD) is where there’s a hole between the two collecting chambers of the heart (the left and right atria). It’s a common type of congenital heart defect that affects about 2 in every 1,000 babies.

When there’s an ASD, extra blood flows through the defect into the right side of the heart, causing it to stretch and enlarge.

Ventricular septal defects

A ventricular septal defect (VSD) is also a common form of congenital heart disease, affecting around 2 in every 1,000 babies. It occurs when there’s a hole between the 2 pumping chambers of the heart (the left and right ventricles).

This means that extra blood flows through the hole from the left to the right ventricle, due to the pressure difference between them. The extra blood goes to the lungs, causing high pressure in the lungs and a stretch on the leftsided pumping chamber. Small holes often eventually close by themselves, but larger holes need to be closed using surgery.

Single ventricle defects

A single ventricle defect is where only one of the pumping chambers (ventricles) develops properly. Without treatment, these defects can be fatal within a few weeks of birth. Nowadays, however, complex heart operations can be carried out which improve longer-term survival, but may leave a person with symptoms and a shortened life span.

Two of the more common single ventricle defects are described below.

Hypoplastic left heart syndrome

Hypoplastic left heart syndrome (HLHS) is a rare type of congenital heart disease, where the left side of the heart doesn’t develop properly and is too small. This results in not enough oxygenated blood getting through to the body.

Tricuspid atresia

Tricuspid atresia is where the tricuspid heart valve hasn’t formed properly. The tricuspid valve separates the right-sided collecting chamber (atrium) and pumping chamber (ventricle). As there’s no blood flow into the right pumping chamber, the pump doesn’t develop and is too small. 

It’s estimated that 10 babies in every 100,000 are affected by tricuspid atresia.

Tetralogy of Fallot

Tetralogy of Fallot is a combination of several defects, affecting about 3 in every 10,000 babies.

The defects making up tetralogy of Fallot are:

  • ventricular septal defect  a hole between the left and right ventricle
  • pulmonary stenosis  narrowing of the pulmonary valve
  • right ventricular hypertrophy  where the muscle of the right ventricle is thickened
  • displaced aorta  where the aorta isn’t in its usual position coming out of the heart

As a result of this combination of defects, oxygenated and non-oxygenated blood mixes, causing the overall amount of oxygen in the blood to be lower than normal. This may cause the baby to appear blue (known as cyanosis) at times.

Total (or partial) anomalous pulmonary venous connection (TAPVC)

TAPVC occurs when the four veins that take oxygenated blood from the lungs to the left side of the heart aren’t connected in the normal way. Instead, they connect to the right side of the heart.

Sometimes, only some of the four veins are connected abnormally, which is known as partial anomalous pulmonary venous connection and may be associated with an atrial septal defect. More rarely, the veins are also narrowed, which can be fatal within a month after birth.

TAPVC is an uncommon type of congenital heart disease, affecting around 7 in every 100,000 babies.

Transposition of the great arteries

Transposition of the great arteries is relatively common, accounting for around 5% of cases of congenital heart disease.

It’s where the pulmonary artery (lung artery) and main body artery (the aorta) are “swapped over” and are connected to the wrong pumping chamber. This leads to blood that’s low in oxygen being pumped around the body.

Truncus arteriosus

Truncus arteriosus is an uncommon type of congenital heart disease, affecting around 5 in every 100,000 babies.

It’s where the two main arteries (pulmonary artery and aorta) don’t develop properly and remain as a single vessel. This results in too much blood flowing to the lungs which, over time, can cause breathing difficulties and damage the blood vessels inside the lungs.

Truncus arteriosus is usually fatal within a year of birth, if it isn’t treated.

Symptoms of congenital heart disease

Congenital heart disease can have a range of symptoms, because the condition refers to several different types of heart defect.

General signs of congenital heart disease can include:

In more severe cases, these problems may develop shortly after birth. However, symptoms sometimes don’t develop until the teenage years or early adulthood.

Read more about the types of congenital heart disease.


Children and adults with congenital heart disease can also develop a range of further problems, such as:

Read more about the complications of congenital heart disease.

Causes of congenital heart disease

Congenital heart disease is caused when something disrupts the normal development of the heart.

It’s thought that most cases occur when something affects the heart’s development during about week five of pregnancy. This is when the heart is developing from a simple tube-like structure into a shape more like a fully-formed heart.

While some things are known to increase the risk of congenital heart disease, no obvious cause is identified in most cases. 

Increased risk

There are a number of things that can increase the chances of a child having congenital heart disease. Some of these are described below.

See types of congenital heart disease for more information on the different heart defects mentioned below. 

Genetic conditions

Several genetic health conditions that a baby inherits from one or both parents can cause congenital heart disease. It’s also recognised that certain types of congenital heart disease run in families.

Down’s syndrome is the most widely-known genetic condition that can cause congenital heart disease. Children with Down’s syndrome are born with a range of disabilities as the result of a genetic abnormality.

About half of all children with Down’s syndrome have congenital heart disease. In 90% of cases, this is a type of septal defect.

Other genetic conditions associated with congenital heart disease include:

  • Turner syndrome  a genetic disorder that only affects females; it’s estimated that 25% of children with Turner syndrome will be born with congenital heart disease, which is usually a type of valve or artery narrowing problem.
  • Noonan syndrome  a genetic disorder that can cause a wide range of potential symptoms; around 80% of children with Noonan syndrome will be born with congenital heart disease, and in about half of all cases, this will be pulmonary stenosis.

Maternal diabetes

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 3-6% of women with diabetes who become pregnant will give birth to a baby with a heart defect  most commonly, transposition of the great arteries.

This increased risk only applies to type 1 diabetes and type 2 diabetes. It doesn’t apply to gestational diabetes, which can develop during pregnancy and usually disappears once the baby is born.

The increased risk is thought to be caused by high levels of the hormone insulin in the blood, which may interfere with the normal development of a foetus.


If a pregnant woman drinks too much alcohol during pregnancy, it can have a poisonous effect on the tissue of the foetus. This is known as foetal alcohol syndrome.

It’s estimated that as many as half of all children with foetal alcohol syndrome will have congenital heart disease  most commonly, ventricular or atrial septal defects.

The Department of Health recommends that pregnant women shouldn’t drink alcohol. If you choose to drink, you shouldn’t drink more than one or two units of alcohol once or twice a week to minimise the risk to your unborn baby.

See Can I drink alcohol if I’m pregnant? for more information about alcohol and pregnancy.


Rubella (German measles) is an infectious condition caused by a virus. It isn’t usually a serious infection for adults or children, but it can have a devastating effect on an unborn baby if a mother develops a rubella infection during the first 8 to 10 weeks of pregnancy.

A rubella infection can cause multiple birth defects, including congenital heart disease. All women of childbearing age should be vaccinated against rubella. The vaccine is now given as part of the routine childhood vaccination schedule. Contact your GP for advice if you’re not sure whether you’ve been vaccinated against rubella.


Women who get flu during the first trimester (three months) of pregnancy are twice as likely to give birth to a baby with congenital heart disease than the general population. The reasons for this are unclear.

The flu vaccine is recommended for all pregnant women.


There are several medications linked to an increased risk of a baby being born with congenital heart disease. These include:

  • certain anti-seizure medications  such as benzodiazepines and lithium
  • certain acne medications  such as isotretinoin and topical retinoids (see treating acne for more information)
  • ibuprofen  women who take the painkiller ibuprofen during the first trimester of their pregnancy are twice as likely to give birth to a baby with congenital heart disease than the general population

Paracetamol is a safer alternative, although ideally you should avoid taking any medicines while you’re pregnant, particularly during the first three months of pregnancy.

See Can I take ibuprofen when I’m pregnant? and Can I take paracetamol when I’m pregnant? for more information and advice.

Speak to your GP or pharmacist if you’re unsure about which medications should be avoided during pregnancy.

Phenylketonuria (PKU)

Phenylketonuria (PKU) is a rare genetic condition present from birth. In PKU, the body can’t break down a chemical called phenylalanine, which builds up in the blood and brain. This can cause learning and behavioural difficulties.

PKU can usually be effectively treated with a low-protein diet and dietary supplements. Pregnant mothers with PKU who don’t do this are six times more likely to give birth to a baby with congenital heart disease than the general population.

Read more about phenylketonuria and pregnancy.

Organic solvents

Women who are exposed to organic solvents are three times more likely to give birth to a baby with congenital heart disease than the general population.

Organic solvents are chemicals found in a wide range of products and substances, such as paint, nail polish and glue.

Diagnosing congenital heart disease

In many cases, congenital heart disease is diagnosed during pregnancy. However, a diagnosis may sometimes only be confirmed after the birth.

Diagnosis during pregnancy

Congenital heart disease may initially be suspected during a routine ultrasound scan of the baby in the womb. Specialist ultrasound called foetal echocardiography will then be carried out at around 18 to 22 weeks of the pregnancy to try to confirm the exact diagnosis.

This may be also undertaken if there’s a family history of congenital heart disease or where there’s an increased risk. Echocardiography is a type of ultrasound scan, where high-frequency sound waves are used to create an image of the heart.

However, it’s not always possible to detect heart defects, particularly mild ones, using foetal echocardiography.

Read more about ultrasound scans during pregnancy.

Diagnosis after the birth

It’s sometimes possible to diagnose a baby with congenital heart disease shortly after birth if some of the characteristic signs or symptoms of congenital heart disease, such as a blue tinge to the skin (cyanosis), are present.

Your baby’s heart will be checked as part of the newborn physical examination. The examination involves observing your baby, feeling their pulse, and listening to their heart with a stethoscope. Heart murmurs are sometimes picked up.

However, some defects don’t cause any noticeable symptoms for several months or even years. You should see your GP if you or your child shows signs of the condition. Further testing can usually help to confirm or rule out a diagnosis.

Further testing

Further tests that may be used to diagnose congenital heart disease are described below.


Echocardiography is often used to check the inside of the heart. Heart problems that were missed during foetal echocardiography can sometimes be detected as a child develops.


An electrocardiogram (ECG) is a test that measures the heart’s electrical activity. Electrodes are placed on the skin around the heart and are connected to a computer. The computer analyses the electrical signals produced by the heart to assess how well it’s beating.

Chest X-ray

A chest X-ray of the heart and lungs can be used to check whether there’s an excess amount of blood in the lungs, or whether the heart is larger than normal. Both may be signs of heart disease.

Pulse oximetry

Pulse oximetry is a test that measures the amount of oxygen present in the blood.

The test involves placing a special sensor on the fingertip, ear or toe that sends out light waves. A computer is connected to the sensor and measures how the light waves are absorbed.

Oxygen can affect how the light waves are absorbed, so by analysing the results, the computer can quickly determine how much oxygen is present in the blood.

Cardiac catheterisation

Cardiac catheterisation is a useful way of obtaining more information about exactly how the blood is being pumped through the heart.

During the procedure, a small, flexible tube called a catheter is inserted into a blood vessel, usually through an artery and/or vein in the groin or arm. The catheter is moved up into the heart, guided by X-rays or sometimes an MRI scanner, and allows pressure measurements in different parts of the heart or lungs to be taken.

A coloured dye that shows up on X-rays can also be injected into the catheter. The dye can be studied as it moves through the heart, allowing the shape and function of each heart chamber, vessels and the lung to be assessed.

Cardiac catheterisation is painless, because it’s carried out under a general anaesthetic or a local anaesthetic.

Coping with a diagnosis

Being told that you or your child has a potentially complex and lifelong condition such as congenital heart disease can be a confusing and frightening experience, even if the condition is relatively mild.

It’s natural to want to find out as much as possible about congenital heart disease, including the available treatments, and how it can affect your life.

Below is a list of charities and support groups you may find useful:

  • The Children’s Heart Federation  a group of charities dedicated to helping people affected by congenital heart disease
  • The Down’s Heart Group  a charity offering support and information on heart conditions associated with Down’s syndrome
  •  a website with a range of stories about children with different types of congenital heart disease, including interviews with their parents

You may also want to find out what help is available for parents who care for children with complex conditions. Read tips for caring for a disabled child.

The specialist nurse at the congenital heart disease department at your hospital can point you in the direction of further information.

Treating congenital heart disease

Treatment for congenital heart disease depends on the specific defect you or your child has.

Mild heart defects don’t usually need to be treated, although it’s likely that you’ll have regular check-ups to monitor your health.

More severe heart defects usually require surgery and long-term monitoring of the heart throughout adult life by a congenital heart disease specialist.

In some cases, medications may be used to relieve symptoms or stabilise the condition before and/or after surgery. 

These may include diuretics to remove fluid from the body and make breathing easier, and digoxin to slow down the heartbeat and increase the strength at which the heart pumps.

Types of congenital heart disease

Treatment plans for the following types of congenital heart defect are described below:

See types of congenital heart disease for descriptions of these defects.

Aortic valve stenosis

The urgency for treatment depends on how narrow the valve is. Treatment may be needed immediately, or it could be delayed until the development of symptoms.

If treatment is required, a procedure called a balloon valvuloplasty is often the recommended treatment option in children and younger people.

During the procedure, a small tube (catheter) is passed through the blood vessels to the site of the narrowed valve. A balloon attached to the catheter is inflated, which helps to widen the valve and relieve any blockage in blood flow.

If balloon valvuloplasty is ineffective or unsuitable, it’s usually necessary to remove and replace the valve using open heart surgery. This is where the surgeon makes a cut in the chest to access the heart.

There are several options for replacing aortic valves, including valves made from animal or human tissue, or your own pulmonary valve. If the pulmonary valve is used, it will be replaced at the same time with a donor pulmonary valve. This type of specialised surgery is known as the Ross procedure. In older children or adults, it’s more likely that metal valves will be used.

Coarctation of the aorta

If your child has the more serious form of coarctation of the aorta that develops shortly after birth, surgery to restore the flow of blood through the aorta is usually recommended in the first few days of life.

Several surgical techniques can be used, including:

  • removing the narrowed section of the aorta and reconnecting the two remaining ends
  • inserting a catheter into the aorta and widening it with a balloon or metal tube (stent)
  • removing sections of blood vessels from other parts of your child’s body and using them to create an aorta in the region of the coarctation or bypass around the site of the blockage (this is similar to a coronary artery bypass graft, which is used to treat heart disease)

Sometimes, older children and adults can develop a newly diagnosed coarctation or partial recurrence of the previous blockage. The main goal of treatment will be to control high blood pressure using a combination of diet, exercise and medication. Some people will need to have the narrowed section of the aorta widened with a balloon and stent.

Read more about treating high blood pressure.

Ebstein’s anomaly

In many cases, Ebstein’s anomaly is mild and doesn’t require treatment. However, surgery to repair the abnormal tricuspid valve is usually recommended if the valve is very leaky. 

If valve repair surgery is ineffective or unsuitable, a replacement valve may be implanted. If Ebstein’s anomaly occurs along with an atrial septal defect (see below), the hole will be closed at the same time.

Patent ductus arteriosus (PDA)

Many cases of PDA can be treated with medication shortly after birth.

Two types of medication have been shown to effectively stimulate the closure of the duct that’s responsible for PDA. These are indomethacin and a special form of ibuprofen.

If the PDA doesn’t close with medication, the duct may be sealed with a coil or plug, which is implanted using a catheter.

Pulmonary valve stenosis

Mild pulmonary valve stenosis doesn’t require treatment, because it doesn’t cause any symptoms or problems.

More severe cases of pulmonary valve stenosis usually require treatment, even if they cause few or no symptoms. This is because there’s a high risk of heart failure in later life if it’s not treated.

As with aortic valve stenosis, the main treatment for pulmonary valve stenosis is a balloon to the pulmonary valve (valvuloplasty). However, if this is ineffective or the valve isn’t suitable for this treatment, surgery may be needed to open the valve (valvotomy) or replace the valve with an animal or human valve.

Septal defects

The treatment of ventricular and atrial septal defects depends on the size of the hole. No treatment will be required if your child has a small septal defect that doesn’t cause any symptoms or stretch on the heart. These types of septal defects have an excellent outcome and don’t pose a threat to your child’s health.

If your child has a larger ventricular septal defect, surgery is usually recommended to close the hole.

A large atrial septal defect and some types of ventricular septal defect can be closed with a special device inserted with a catheter. If the defect is too big or not suitable for the device, surgery may be needed to close the hole. 

Unlike open heart surgery, the catheter procedure doesn’t cause any scarring and is associated with just a small bruise in the groin. Recovery is very quick. This procedure is undertaken in specialist units that treat congenital heart problems in children and a small number of additional adult centres.

Single ventricle defects

Tricuspid atresia and hypoplastic left heart syndrome are treated in much the same way.

Shortly after birth, your baby will be given an injection of medication called prostaglandin. This will encourage the mixing of oxygen-rich blood with oxygen-poor blood. The condition will then need to be treated using a three-stage procedure.

The first stage is usually performed during the first few days of life. An artificial passage known as a shunt is created between the heart and lungs, so blood can enter the lungs. However, not all babies will need a shunt.

The second stage will be performed when your child is four to six months old. The surgeon will connect veins that carry oxygen-poor blood from the upper part of the body (Superior Vena Cava) directly to your child’s pulmonary artery. This will allow blood to flow into the lungs, where it can be filled with oxygen.

The final stage is usually performed when your child is 18 to 36 months old. It involves connecting the remaining lower body vein (Inferior Vena Cava) to the pulmonary artery, effectively bypassing the heart itself.

Tetralogy of Fallot

Tetralogy of Fallot is treated using surgery. If your baby is born with severe symptoms, surgery may be recommended soon after birth.

If the symptoms are less severe, surgery will usually be carried out when your child is three to six months old.

During the operation, the surgeon will close the hole in the heart and open up the narrowing in the pulmonary valve.

Total anomalous pulmonary venous connection (TAPVC)

TAPVC is treated with surgery. During the procedure, the surgeon will reconnect the abnormally positioned veins into the correct position in the left atrium.

The timing of surgery will usually depend on whether your child’s pulmonary vein (the vein that connects the lungs and heart) is also obstructed.

If the pulmonary vein is obstructed, surgery will be performed after birth. If the vein isn’t obstructed, surgery can often be postponed until your child is a few weeks or months old.

Transposition of the great arteries

As with treatment for single ventricle defects, your baby will be given an injection of a medication called prostaglandin shortly after birth. This will prevent the passage between the aortic and pulmonary valve (the ductus arteriosus) closing after birth.

Keeping the ductus arteriosus open means that oxygen-rich blood is able to mix with oxygen-poor blood, which should help relieve your baby’s symptoms.

In some cases, it may also be necessary to use a catheter to create a temporary hole in the atrial septum (the wall that separates the two upper chambers of the heart) to further encourage the mixing of blood.

Once your baby’s health has stabilised, it’s likely that surgery will be recommended. This should ideally be carried out during the first month of the baby’s life. A surgical technique called arterial switch is used, which involves detaching the transposed arteries and reattaching them in the correct position.

Truncus arteriosus

Once your baby is in a stable condition, surgery will be used to treat truncus arteriosus. This is usually carried out within a few weeks after birth.

The abnormal blood vessel will be split in two to create two new blood vessels, and each one will be reconnected in the correct position.

Complications of congenital heart disease

Children and adults with congenital heart disease are at an increased risk of developing further problems.

Developmental problems

Many children with congenital heart disease experience delays in their development. For example, they may take longer to start walking or talking. They may also have lifelong problems with physical co-ordination.

Some children with congenital heart disease also have learning difficulties. These are thought to be caused by a poor oxygen supply during early life, which affects the development of the brain.

Natural intelligence is usually unaffected, but some children often perform well below the academic level they would be expected to reach.

This is because of problems such as:

  • impaired memory
  • problems expressing themselves using language
  • problems understanding the language of others
  • low attention span and difficulty concentrating
  • poor planning abilities
  • poor impulse control  acting rashly without thinking about the possible consequences

These can lead to problems with social interaction and behaviour in later life.

Respiratory tract infections

The risk of developing respiratory tract infections (RTIs) is higher in people with congenital heart disease. RTIs are infections of the lungs and airways, such as pneumonia.

Symptoms of an RTI can include:

  • a cough, which can be severe and bring up phlegm and mucus
  • wheezing
  • rapid breathing
  • chest tightness

Treatment for an RTI depends on the cause. For example, infections caused by bacteria can be treated with antibiotics.


People with congenital heart disease also have an increased risk of developing endocarditis. This is an infection of the lining of the heart and valves, or both. If it’s not treated, it can cause life-threatening heart damage.

Symptoms of endocarditis can include:

  • a high temperature (fever) of 38C (100.4F) or above
  • chills
  • loss of appetite
  • headache 
  • muscle and joint pain
  • night sweats
  • shortness of breath 
  • persistent cough

Endocarditis will need to be treated in hospital with antibiotic injections.

The condition usually develops when an infection in another part of the body, such as on the skin or the gums, spreads through the blood and into the heart.

As gum disease can potentially lead to endocarditis, it’s very important to maintain excellent oral hygiene if you have congenital heart disease.

It’s also usually recommended that you avoid having any cosmetic procedure that involves piercing the skin, such as tattoos or body piercings.

Pulmonary hypertension

Some types of congenital heart disease can cause the blood pressure inside the arteries that connect the heart and lungs to be much higher than it should be. This is known as pulmonary hypertension.

Symptoms of pulmonary hypertension can include:

  • shortness of breath
  • extreme tiredness 
  • dizziness
  • feeling faint
  • chest pain 
  • a rapid heartbeat

A range of medications can be used to treat pulmonary hypertension. Read more about treating pulmonary hypertension.

Heart rhythm problems

Children and adults with congenital heart disease are at risk of developing different types of heart rhythm problems. These may come from the top of the heart (atrial arrhythmia) or from the ventricular chambers, which are more concerning (ventricular arrhythmia).

At rest, a normal heart rate is between 60 and 100 beats a minute. The heart may either beat too slowly, which may require a pacemaker, or too fast, which may require medication or, rarely in a child, an implantable cardioverter defibrillator to deliver an electric shock to the heart to stop the rhythm problem.

There are two particular fast rhythms that come from the top of the heart and become more common with age. These are atrial fibrillation and atrial flutter.

Sudden cardiac death

There’s a small but significant risk of sudden cardiac death in people with a history of congenital heart disease. It’s estimated that 1 in every 1,000 adults with congenital heart disease die suddenly in this way every year.

Identifying people at risk of sudden cardiac death is difficult, but those with higher risk ventricular arrhythmias should be fitted with an implantable cardioverter defibrillator.

However, many people have a sudden cardiac death without a rhythm problem being identified, so it’s a concern for most people with congenital heart disease.

Heart failure

Heart failure is where the heart can’t pump enough blood around the body to meet the body’s needs. It can occur shortly after a baby with a severe congenital heart defect is born, or as a later complication, of any treated or untreated type of congenital heart disease.

Symptoms of heart failure can include:

  • breathlessness when you’re active or sometimes resting
  • extreme tiredness and weakness
  • swelling in the abdomen (tummy), legs, ankles and feet

Treatments for heart failure can include medication and the use of an implanted device such as a pacemaker.

Many types of surgery for congenital heart disease are referred to as palliative, because they’re not able to perfectly recreate a normal physiological circulation. This is particularly true for people with tricuspid atresia and single ventricles. Although palliative surgery may work well for many decades, there are elements of this unusual circulation that can fail.

In this case, medication and alternative surgery or interventional procedures may be necessary. Ultimately, if there are severe symptoms of heart failure that don’t improve with treatment, a heart transplant may need to be considered. However, in the UK, relatively few heart transplants are carried out each year, because of the shortage of donated hearts.

Read more about treating heart failure.

Blood clots

Having a history of congenital heart disease can also increase the risk of a blood clot forming inside the heart and travelling up to the lungs or brain.

This can lead to a pulmonary embolism (where the blood supply to the lungs is blocked) or a stroke (where the blood supply to the brain is blocked).

Medications can be used to prevent, dissolve or remove blood clots.

Preventing congenital heart disease

As so little is known about the causes of congenital heart disease, there’s no guaranteed way of avoiding having a baby with the condition.

However, if you’re pregnant, the following advice can help reduce the risk:

  • Ensure you are vaccinated against rubella and flu.
  • Avoid drinking alcohol or taking drugs.
  • Take 400 micrograms of folic acid supplement a day during the first trimester (first 12 weeks) of your pregnancy  this lowers your risk of giving birth to a child with congenital heart disease, as well as several other types of birth defect.
  • Check with your GP or pharmacist before you take any medication during pregnancy, including herbal remedies and medication that’s available over the counter.
  • Avoid contact with people who are known to have an infection.
  • If you have diabetes, make sure it’s controlled.
  • Avoid exposure to organic solvents, such as those used in dry cleaning, paint thinners and nail polish remover.

See vitamins and nutrition in pregnancy, infections in pregnancy and your antenatal care for more information and advice.

If you have congenital heart disease and become pregnant, your congenital heart specialist will usually arrange an echocardiogram (heart scan) for your baby approximately 20 weeks into your pregnancy. This is to check whether your baby has any evidence of congenital heart disease. This scan will be in addition to your usual antenatal ultrasound scans.