Congenital Heart Defects
What are congenital heart defects?
Congenital (kon-JEN-i-tal) heart defects are problems with the heart's structure that are present at birth. These defects can involve the interior walls of the heart, valves inside the heart, or the arteries and veins that carry blood to the heart or out to the body. Congenital heart defects change the normal flow of blood through the heart.
There are many different types of congenital heart defects. They range from simple defects with no symptoms to complex defects with severe, life-threatening symptoms.
Congenital heart defects are the most common type of birth defect, affecting 8 of every 1,000 newborns. Each year, more than 35,000 babies in the US are born with congenital heart defects. Most of these defects are simple conditions that are easily fixed or need no treatment.
A small number of babies are born with complex congenital heart defects that need special medical attention soon after birth. Over the past few decades, the diagnosis and treatment of these complex defects has greatly improved.
As a result, almost all children with complex heart defects grow to adulthood and can live active, productive lives because their heart defects have been effectively treated.
Most people with complex heart defects continue to need special heart care throughout their lives. They may need to pay special attention to certain issues that their condition could affect, such as health insurance, employment, pregnancy and contraception, and preventing infection during routine health procedures.
Types of congenital heart defect:
Holes in the heart can occur:
- In the upper chambers (atrial septal defects)
- In tower chambers (ventricular septal defects)
- Between all four chambers (atrioventricular septal defects)
- In the great artery, which is called patent ductal arteriosus
The holes are part of the circulation system in the foetus but should close up after birth.
More complex conditions include tetralogy of Fallot. The main symptom is cyanosis, and for this reason babies with this problem are commonly known as 'blue babies'.
In tetralogy of Fallot, the baby has a large hole in the heart, allowing blood to pass from the right ventricle to the left without going through the lungs. There is a narrowing at or just below the pulmonary valve, the right ventricle is more muscular than normal and the aorta lies directly over the hole - the ventricular septal defect.
Babies may have rapid breathing or fall unconscious. Older children may become short of breath and faint.
An obstruction, or stenosis, can occur between the valves between the upper and lower chambers of the heart. More frequently, the obstruction is between the ventricles and trunks coming from them, either the valve to the lungs or the valve to the body.
Only severe aortic stenosis requires surgery, and some children may have the condition without showing any symptoms. The obstruction can also be within the vessels themselves. In this case, the narrowing is within the artery and effects supplies of blood to different parts of the body. This defect may not be picked up for many years.
Congenital heart disease (CHD) can describe a number of different problems affecting the heart. It is the most common type of birth defect. Congenital heart disease is responsible for more deaths in the first year of life than any other birth defects. Many of these defects need to be followed carefully. Some heal over time, others will require treatment. Congenital heart disease is often divided into two types: cyanotic (blue discoloration caused by a relative lack of oxygen) and non-cyanotic. The following lists cover the most common of the congenital heart diseases:
- Tetralogy of Fallot
- Transposition of the great vessels
- Tricuspid atresia
- Total anomalous pulmonary venous return
- Truncus arteriosus
- Hypoplastic left heart
- Pulmonary atresia
- Some forms of total anomalous pulmonary venous return
- Ebstein's anomaly
- Ventricular septal defect (VSD)
- Atrial septal defect (ASD)
- Patent ductus arteriosus (PDA)
- Aortic stenosis
- Pulmonic stenosis
- Coarctation of the aorta
- Atrioventricular canal (endocardial cushion defect)
These problems may occur alone or together. The majority of congenital heart diseases occurs as an isolated defect and is not associated with other diseases. However, they can also be a part of various genetic and chromosomal syndromes such as Down syndrome, trisomy 13, Turner syndrome, Marfan syndrome, Noonan syndrome, and DiGeorge syndrome.
No known cause can be identified for most congenital heart defects. Congenital heart diseases continue to be investigated and researched. Drugs such as retinoic acid for acne, chemicals, alcohol, and infections (such as rubella) during pregnancy can contribute to some congenital heart problems.
Symptoms depend on the specific condition. While congenital heart disease is present at birth, the symptoms may not be immediately obvious. Defects such as coarctation of the aorta may not cause problems for many years. Other problems, such as a small ventricular septal defect (VSD), may never cause any problems, and some people with a VSD have normal physical activity and a normal life span.
Exams and Tests
Diagnostic tests depend on the specific condition.
Treatment depends on the specific condition. Some congenital heart diseases can be treated with medication alone, while others require one or more surgeries.
In tetralogy of Fallot, surgery may be needed to increase blood flow to the lungs with a shunt, linking the aorta and the pulmonary artery. The child is able to develop and the defect can be corrected later.
An arterial switch operation may be necessary to reconnect the arteries correctly. With holes in the heart, oxygenated, red blood from the lungs passes into the right side of the heart, where it mixes with bluish blood and is sent back to the lungs. The heart is put under extra strain, potentially causing it to enlarge and causing high blood pressure and blood vessel damage. Growth and nourishment are affected.
Holes in the heart are closed with one or two patches and the single valve is divided into two. Blood circulation should be returned to normal but the reconstructed valve may not work normally.
If the defect is too complex to repair in infancy, a pulmonary artery band may be surgically used to reduce blood flow and high pressure in the lungs (pulmonary hypertension). The band is later removed and surgery carried out.
Balloon valvuloplasty, which involves threading a balloon through a dilated heart valve, is usually used to correct pulmonary valvular stenosis, although open-heart surgery may be necessary.
How well a patient does depends on the specific defect.
Complications depend on the specific condition and treatment.
When to Contact a Medical Professional
Call your health care provider if you suspect that your child has a heart problem.
Avoid alcohol and other drugs during pregnancy. Doctors should be made aware that a woman is pregnant before prescribing any medications for her. A blood test should be done early in the pregnancy to see if the woman is immune to rubella. If the mother is not immune, she must avoid any possible exposure to rubella and should be immunized immediately following delivery.
Poorly controlled blood sugar levels in women who have diabetes during pregnancy are also associated with a high rate of congenital heart defects during pregnancy.
Experts believe that some prescription and over-the-counter medications and street drugs used during pregnancy increase the risk of heart defects.
and street drugs used during pregnancy increase the risk of heart defects. There may be some hereditary factors that play a role in congenital heart disease. Genetics does appear to play a role in many diseases, and multiple family members may be affected. Talk to your health care provider about screening.
Expectant mothers should receive good prenatal care. Many congenital defects can be discovered on routine ultrasound examinations performed by an obstetrician. The delivery can then be anticipated and the appropriate medical personnel (such as a pediatric cardiologist, a cardiothoracic surgeon, and a neonatologist) can be present, and ready to help as necessary. Such preparation can mean the difference between life and death for some babies.