What are other names for congenital heart defects?
- Congenital heart disease
- Cyanotic heart disease
- Heart defects
- Congenital cardiovascular malformations
Types :
Most heart defects either obstruct blood flow in the heart or vessels near it, or cause blood to flow through the heart in an abnormal pattern. Rarely defects occur in which only one ventricle (single ventricle) is present, or both the pulmonary artery and aorta arise from the same ventricle (double outlet ventricle). A third rare defect occurs when the right or left side of the heart is incompletely formed — hypoplastic heart.
The following defects are described in this section:
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Patent ductus arteriosus (PDA)
Obstruction defects
- Pulmonary stenosis
- Aortic stenosis
- Coarctation of the aorta
- Bicuspid aortic valve
- Subaortic stenosis
- Ebstein's anomaly
Septal defects
- Atrial septal defect (ASD)
- Ventricular septal defect (VSD)
- Eisenmenger's complex
- Atrioventricular (A-V) canal defect (also calledendocardial cushion defect or atrioventricular septal defect)
Cyanotic defects
- Tetralogy of Fallot
- Transposition of the great arteries
- Tricuspid atresia
- Pulmonary atresia
- Truncus arteriosus
- Total anomalous pulmonary venous (P-V) connection
Hypoplastic left heart syndrome
Causes :
The cause may be due to a genetic predisposition or an environmental exposure during pregnancy.
Known genetic causes of heart disease includes chromosomal abnormalities such as trisomies 21, 13, and 18, as well as a range of newly recognised genetic point mutations, point deletions and other genetic abnormalities as seen in syndromes such as Velo-Cardio-Facial Syndrome, familial ASD with heart block, Alagille syndrome, Noonan syndrome, and many more.
Known antenatal environmental factors include maternal infections (Rubella), drugs (alcohol, hydantoin, lithium and thalidomide) and maternal illness (diabetes mellitus, phenylketonuria, and systemic lupus erythematosus)
Signs and Symptoms:
Many congenital heart defects have few or no symptoms. A doctor may not even detect signs of a heart defect during a physical exam.
Some heart defects do have symptoms. These depend on the number and type of defects and how severe the defects are. Severe defects can cause symptoms, usually in newborn babies. These symptoms can include:
- Rapid breathing
- Cyanosis (a bluish tint to the skin, lips, and fingernails)
- Fatigue (tiredness)
- Poor blood circulation
Congenital heart defects don't cause chest pain or other painful symptoms.
Abnormal blood flow through the heart caused by a heart defect will make a certain sound. Your doctor can hear this sound, called a heart murmur, with a stethoscope. However, not all murmurs are a sign of a congenital heart defect. Many healthy children have heart murmurs.
Normal growth and development depend on a normal workload for the heart and normal flow of oxygen-rich blood to all parts of the body. Babies with congenital heart defects may have cyanosis or tire easily when feeding. Sometimes they have both problems. As a result, they may not gain weight or grow as they should.
Older children may get tired easily or short of breath during exercise or activity. Many types of congenital heart defects cause the heart to work harder than it should. In severe defects, this can lead to heart failure, a condition in which the heart can't pump blood strongly throughout the body. Symptoms of heart failure include:
- Fatigue with exercise
- Shortness of breath
- A buildup of blood and fluid in the lungs
- A buildup of fluid in the feet, ankles, and legs
Diagnosis :
Antenatal diagnosis
An increasing number of cases of congenital heart disease are now diagnosed before a baby is born. This can be done by carrying out a foetal echocardiography.
A foetal echocardiography is a type of ultrasound scanner that has been specially designed to build a picture of the insides of the chambers of the heart.
Foetal echocardiography should be carried out during routine antenatal examinations, usually some time between the 18th and 20th week of pregnancy.
However, it is not always possible to detect heart defects (particularly mild ones) using a foetal echocardiography.
Postnatal diagnosis
If a baby is born with cyanotic heart disease, a diagnosis can usually be made quickly and confidently due to the distinctive blue colour of their skin.
If your baby is born with acyanotic heart disease, their symptoms may not become immediately apparent for several months, or possibly years, after birth. In some types of acyanotic heart disease, symptoms are not apparent until a child reaches three years of age.
Possible signs that your child may have acyanotic heart disease include:
- problems feeding,
- slow growth,
- shortness of breath after exercising,
- tiredness after exercising, and
- swelling of their hands, feet and ankles.
Tests Commonly Used To Diagnosis Congenital Heart Defects
- Echocardiogram
- ECG
- Chest X Ray
- Pulse Oximetry
- Cardiac Catheterization
There are a number of different surgical techniques that can be used to treat congenital heart disease.
Catheters
A catheter, similar to the tube that is used during diagnosis, is inserted into the heart, and tools are passed down the catheter to repair the heart defects.
The advantage of this type of surgery is that it is non-invasive, which means that your child will not have to have a major surgical incision (cut) made in their chest.
Open heart surgery
For more serious types of heart defects, it may be necessary to operate directly on the heart. During open heart surgery, the heart will be stopped and a machine used to pump blood around your child’s body.
An incision is made in your child’s chest so that the heart defects can be surgically repaired, or damaged parts of the heart, such as the valves, can be replaced.
Heart transplant
In the most serious cases of congenital heart disease, it may be necessary to remove the damaged heart and replace it with a healthy heart that has been donated by the family of a child who has recently died.
Treatment for common types of congenital heart disease
Specific treatments for the most common types of congenital heart disease are described below.
Septal defects
If your child is diagnosed with a ventricular septal defect (VSD) or an atrial septal defect (ASD), the recommended treatment will depend on the size of the defect.
If the defect is small, a policy of ‘watchful waiting’ may be recommended, where your child receives no immediate treatment but their health is carefully monitored. This is because 90% of small defects will close as the child grows older.
In cases of mild to medium-sized defects, it may be possible to seal the defect using a catheter. The catheter is guided to the site of the hole, and a specially designed mesh is passed through the catheter to seal the defect.
In cases of medium to large-sized defects, open heart surgery will probably be required. This involves a patch being stitched directly over the defect.
Stenosis
If your child is diagnosed with stenosis (narrowing of their aorta or pulmonary valve) the treatment that is recommended will depend on the extent of the stenosis.
In mild cases, a policy of ‘watchful waiting’ may be recommended. Medication 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 known as a balloon angioplasty. Once the valve has been widened, the balloon is removed. Sometimes, a metal coil (stent) is used to keep the valve widened.
In the most serious cases of stenosis, it is sometimes necessary to replace the valve during open heart surgery.
Replacement valves can be obtained from human donors, or 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.
An alternative technique, which involves using a catheter to replace the aortic valve, has recently become available. The technique is known as catheter insertion of a new aortic valve.
The catheter is passed through the groin and up into the heart, and then a replacement valve is moved through the catheter and into position.
As yet, there is not enough available evidence on the long-term safety or effectiveness of catheter insertion. Therefore, this type of treatment is usually only recommended for people who are too ill or weak to withstand the effects of open heart surgery.
Patent ductus ateriosus (PDA)
Many cases of patent ductus ateriosus (PDA) can be treated shortly after birth, using medication.
Two types of medication - indomethacin and ibuprofen - have been shown to effectively stimulate the closure of the duct that is responsible for PDA.
If a PDA does not respond to medication, a catheter can be used to seal the duct with a metal coil or plug.
Tetralogy of Fallot (TOF)
Babies born with Tetralogy of Fallot (FOT) who are experiencing severe symptoms of breathlessness may require emergency surgery to restore normal lung function. This can be done using a procedure known as a Blalock-Taussig shunt (a BT shunt).
During a BT shunt, an artery is diverted (or shunted) into the lungs so that a supply of oxygen-rich blood becomes available.
Further open heart surgery is then recommended when the baby is old enough to withstand the after-effects of surgery. During open heart surgery, the defect between the ventricles is sealed and the pulmonary valve is widened.
Transposition of the great arteries (TGA)
Transposition of the great arteries (TGA) will require open heart surgery, which is usually done shortly after your baby is born.
A surgical technique, known as an arterial switch, is usually used to treat cases of TGA. During an arterial switch, the arteries that are connected to the pulmonary and aortic valves are cut and reattached to their correct position on the other side of the heart.
Congenital heart disease in adulthood
About 85% of children with congenital heart disease will respond well to treatment and survive into adulthood. Living as an adult with congenital heart disease involves a new set of challenges.
Some adults will require specialised care. Routine medical procedures, such as giving birth or having a general anaesthetic, will need to be carried out by specialist staff with experience in treating adults with congenital heart disease.
There is also the risk that previous heart surgery, such as the insertion of a replacement valve, will fail and that further surgery will be required.
Due to these factors, it is recommended that older teenagers register with a specialised adult congenital heart disease clinic. The clinic will be able to provide regular check-ups and assessments, liaise with other specialised medical services as required, and provide ongoing support and advice.
Congenital Heart Disease At A Glance :
- Congenital heart defects are problems with the heart's structure that are present at birth. Congenital heart defects change the normal flow of blood through the heart.
- Congenital heart defects are the most common type of birth defect, affecting 8 out of every 1,000 newborns. Each year, more than 35,000 babies in the United States are born with congenital heart defects.
- There are many types of congenital heart defects ranging from simple to very complex.
- Doctors don't know what causes most congenital heart defects. Heredity may play a role.
- Although many heart defects have few or no symptoms, some do. Severe defects can cause symptoms such as:
- Rapid breathing.
- A bluish tint to skin, lips, and fingernails. This is called cyanosis.
- Fatigue (tiredness).
- Poor blood circulation.
- Rapid breathing.
- Serious heart defects are usually diagnosed while a baby is still in the womb or soon after birth. Some defects aren't diagnosed until later in childhood, or even in adulthood.
- An echocardiogram is an important test for both diagnosing a heart problem and following the problem over time. This test helps diagnose problems with how the heart is formed and how well it's working. Other tests include EKG (electrocardiogram), chest x ray, pulse oximetry, and cardiac catheterization.
- Doctors treat congenital heart defects with catheter procedures and surgery.
- Treatment depends on the type and severity of the defect.
- With new advances in testing and treatment, most children with congenital heart defects grow into adulthood and can live healthy, productive lives. Some need special care all though their lives to maintain a good quality of life.
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