Coarctation of the Aorta in Children
Basics of Coarctation of the Aorta
The aorta is the major blood vessel that carries blood away from the heart to the body. When a child has coarctation of the aorta, the aorta is narrowed at some point.
The aorta is shaped like a candy cane. The first section moves up toward the head (ascending aorta), then curves into a C-shape as smaller arteries attached to it carry blood to the head and arms (aortic arch). Beyond the curve, the aorta straightens again and moves downward towards the abdomen, carrying blood to the lower part of the body (descending aorta).
The narrowed segment (called “coarctation”) can occur anywhere in the aorta, but is most common in the segment just after the aortic arch. This 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 might not even cause symptoms. In other cases, the aorta is more constricted, placing a strain on the heart’s left ventricle, the chamber that pumps blood to the aorta and out to the body. With more severe narrowing, there are more symptoms, increasing the likelihood the defect will be detected when a child is very young. While some infants are diagnosed with coarctation, the problem can go undetected until adolescence.
Fast Facts of Coarctation of the Aorta
- Thirty percent to 40 percent of children with coarctation of the aorta also have a bicuspid aortic valve — a valve that has two leaflets instead of the usual three.
- Coarctation of the aorta occurs in about 6 percent to 8 percent of all children with congenital heart disease.
- Boys have the defect twice as often as girls.
Causes of Coarctation of the Aorta
Coarctation of the aorta is a congenital (present at birth) defect. Doctors don’t know for sure why certain people are born with this defect.
Symptoms of Coarctation of the Aorta
Each child may experience symptoms of coarctation of the aorta differently, but the most common ones include:
- Pale skin
- Heavy and/or rapid breathing
- Poor feeding
- Poor weight gain
- Cold feet and/or legs
- Diminished or absent pulses in the feet
- Blood pressure in the arms significantly greater than the blood pressure in the legs
Mild narrowing may cause no symptoms. Often, a school-age child or adolescent is diagnosed with high blood pressure or a heart murmur during a physical examination. Some children complain of headaches or cramps in the lower sections of their body.
The symptoms of coarctation of the aorta can resemble other medical conditions or heart problems, so it is important to consult with a child's physician for a diagnosis.
Health Problems Related to Coarctation of the Aorta
Coarctation of the aorta can create health problems if left untreated. Below are a few examples.
- Because the left ventricle must work harder to try to move blood through the narrowing in the aorta, eventually it will be unable to handle the extra workload and fail to pump blood efficiently.
- With blood pressure higher above the narrowing and lower below it, older children may have headaches from too much pressure in the head’s blood vessels. They may also suffer from cramps in the legs or abdomen from too little blood flow in that region. Meanwhile, the kidneys may not make enough urine because they need the right blood flow and right blood pressure to perform the task.
- High blood pressure may weaken the walls of the ascending aorta, the aortic arch or any of the arteries in the head and arms. The weakening can lead to spontaneous tears in any of these arteries and potentially cause a stroke or uncontrollable bleeding.
- With coarctation of the aorta, there is a higher than average chance of developing an infection in the valves of the heart (known as “bacterial endocarditis”) or an infection in the aorta itself (“bacterial endarteritis”). Both complications are exceedingly rare.
- The coronary arteries, which supply oxygen-rich (red) blood to the heart muscle, may narrow in response to elevated pressure.
Tests, Procedures and Diagnosis of Coarctation of the Aorta
When a child's physician hears a heart murmur during a physical examination, the physician may refer the child to a pediatric cardiologist, who specializes in the diagnosis and treatment of congenital heart defects and heart problems that may develop later in childhood. To make a diagnosis, a cardiologist performs a physical examination, listens to a child's heart and lungs, and makes other observations. Heart murmurs are evaluated on the basis of pitch, loudness and duration, which give the cardiologist an initial idea of which heart problem a child may have. Diagnostic testing for congenital heart disease varies by a child's age and clinical condition, and may include:
- Chest X-ray. This diagnostic test uses X-ray energy beams to produce images onto film of internal tissues, bones and organs.
- Electrocardiogram (ECG or EKG). A test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias) and detects heart muscle damage.
- Echocardiogram (or “echo”). A procedure that evaluates the structure and function of the heart by using sound waves recorded on an electronic sensor that produces a moving picture of the heart and its valves. The vast majority of aortic coarctations are diagnosed by echocardiography.
- Cardiac catheterization (or “cath”). During this diagnostic procedure, a catheter is carefully threaded through the arteries and veins of the groin and advanced up to the heart. Dye is squirted into the heart and aorta and pictures are taken of the anatomy. Catheterization may also be used to repair the coarctation if a child is large enough.
- Magnetic resonance imaging (MRI). This diagnostic procedure uses a combination of large magnets, radiofrequencies and a computer to produce detailed images of organs and structures within the body.
Treatment of Coarctation of the Aorta
A child’s physician determines the specific treatment for coarctation of the aorta based on:
- A child's age, overall health and medical history
- Severity of the disease
- A child's tolerance for specific medications, procedures or therapies
- Expectations for the course of the defect
- Parents’ opinions or preferences
Coarctation of the aorta is treated by repairing the narrowed vessel. Options include:
- Interventional cardiac catheterization. During this procedure, the child is sedated, and a small, thin, flexible tube (catheter) is inserted into a blood vessel in the groin and gently guided to the inside of the heart. Once the catheter is in the heart, the cardiologist passes an inflated balloon through the narrowed section of the aorta to open the area. A small device called a stent may also be placed in the narrowed area after the balloon dilation to keep the aorta open. Following the procedure, most children remain in the hospital for an overnight observation.
- Surgical repair. Coarctation of the aorta may be repaired during surgery while a child is under general anesthesia. The narrowed area may be surgically removed or made larger with the help of surrounding structures or a patch.