The aorta is the major blood vessel that carries blood away from the heart to the body. When someone has coarctation of the aorta, the aorta is narrowed at some point.
Here's how a healthy heart and aorta work: Blood that needs oxygen comes from all over the body and enters the right side of the heart, which pumps it to the lungs. The lungs fill the blood with oxygen, and this oxygen-rich blood returns from the lungs to the left side of the heart. The left side of the heart finishes up by pumping the blood out through the aorta. From the aorta, the blood travels through arteries that reach all of the body's organs and tissues, bringing them oxygen. Then the blood returns to the heart through veins and begins the cycle once again.
When part of the aorta is narrowed, called a coarctation, that defect can affect the body's blood circulation because the left side of the heart has to work harder to pump blood through the narrowed aorta. Sometimes the narrowing is minor and may not even cause symptoms. In other cases the aorta may be more constricted, placing a strain on the heart's left ventricle (the chamber that pumps blood to the aorta and out to the body). A coarctation can occur anywhere in the aorta, but it is most often found after the point where the arteries that carry blood to the upper body and head branch off from the aorta.
What Causes Coarctation of the Aorta?
Coarctation of the aorta (or COA for short) is a congenital defect, meaning that someone is born with it. About 1 in 100 children is born with a heart problem, and coarctation represents about 8% of cases. Doctors don't know for sure why certain people are born with this narrowing of the aorta.
Coarctation occurs more commonly in boys. However, it is commonly seen in girls with Turner syndrome, in which one of a girl's two X chromosomes is incomplete or missing. COA may occur with other birth defects or congenital heart conditions, such as a ventricular septal defect (a hole in the wall between the heart's left and right ventricles).
Coarctation can also be associated with abnormalities of the other structures of the left side of the heart. A common association is a bicuspid aortic valve, in which the aortic valve between the left ventricle and aorta has two leaflets instead of the normal three.
Most people with COA are diagnosed when they are babies or young children. But some may not be diagnosed until they are teens or even adults. Usually, in this case, the narrowing in the aorta is not severe enough to cause serious symptoms while the person is very young. But even those who do not have major symptoms usually need to be treated because the coarctation can eventually cause problems. COA will not go away on its own.
Signs and Symptoms
Often an abnormal blood pressure test is the first sign of COA detected by a doctor. During a physical exam, the doctor may find that a child with a coarctation has a higher blood pressure in the arms than in the legs. The doctor may also hear a heart murmur or notice that the pulse in the groin is weak or difficult to feel. Any person diagnosed with high blood pressure should be checked for coarctation of the aorta.
Kids who have COA often do not have any symptoms and have only mild signs that are discovered by accident during a regular visit to the doctor. A child who does have symptoms may experience some or all of these:
- cold legs and feet
- shortness of breath, especially when exercising
- chest pain
Diagnosis and Treatment
Doctors may refer a child with the signs or symptoms of COA to a pediatric cardiologist — a doctor who specializes in diagnosing and treating heart disease in kids and teens. The cardiologist will listen to the heart, feel the pulses, and check blood pressure. The doctor will probably order an echocardiogram, a test that uses sound waves to create a picture of the heart and its circulation. Other tests that produce images of the heart, such as a chest X-ray, a magnetic resonance imaging (MRI) test, or a computerized tomography (CT) scan, may also be used to help the cardiologist look for a narrowing of the aorta.
A severe coarctation is usually diagnosed shortly after birth and repaired by surgery immediately. In an older patient, doctors often recommend that COA be treated quickly, since it can cause persistent high blood pressure and cause heart enlargement. The defect can also cause dissection or rupture of the aorta, which can be fatal in many people by the age of 40.
Coarctation of the aorta can be repaired either by surgery or other procedures. Different types of surgery can repair a narrowing of the aorta, but one of the most common ways to fix COA is to remove the narrow section and reconnect the two ends of the aorta.
In some cases, doctors may choose to do a procedure known as balloon dilation or balloon angioplasty. They insert a tiny balloon into a blood vessel in the leg and use a very thin wire to thread it up to the aorta, across the narrow area. When the doctor inflates the balloon, the narrow area is expanded. After the area has been widened, the balloon is removed. The cardiologist may also implant a device called a stent to keep the area open after the procedure.
Home Care
Once the defect has been fixed, most symptoms of COA disappear right away because the blockage that caused those symptoms is now gone. Some people will still have high blood pressure for a while and may have to take medicine to control it.
Kids and teens who have had surgery often feel completely better after a week or two, and those who have had the balloon treatment feel better even sooner, often within a couple of days. But doctors recommend that all patients avoid some physical activities — especially lifting heavy objects or sports that could cause an impact to the chest — for several weeks or months to give their bodies enough time to heal. Someone whose blood pressure remains high may have to continue to limit certain activities as long as the blood pressure remains high.
Kids who've had a COA corrected will still need to be monitored over time. In some, the narrowing of the aorta can return after surgery or balloon dilation treatment. Regular visits to a cardiologist — often every year or two after recovery — let the doctor monitor blood pressure and look for signs that COA could be returning.
If your child has COA or has had a coarctation repaired, call the doctor if he or she has shortness of breath, chest pain, or fainting. Overall, kids who have had coarctation of the aorta can expect to continue leading a normal life after their treatment.