Coarctation of the Aorta

What is Coarctation of the Aorta?

The aorta (pronounced: ay-or-t uh) is the major blood vessel that carries blood away from the heart to the body. When someone has coarctation of the aorta, that person's aorta is narrowed at some point.

This disorder involves a narrowing (coarctation) of the aorta, usually just below the left subclavian artery and near the site where the ligamentum arteriosum joins the pulmonary artery to the aorta.The ligamentum arteriosum is a remnant of a fetal blood vessel called the ductus arteriosus.

Coarctation may be associated with mitral or aortic valve lesions (usually the bicuspid aortic valve) and with severe cases of hypoplasia of the aortic arch, patent ductus arteriosus, or a ventricular septal defect.

This disorder accounts for about 8% of all congenital heart defects in children and is more common in males than in females. When it occurs in females, it commonly is associated with Turner's syndrome, a chromosomal disorder that causes ovarian dysgenesis.

The prognosis for coarctation of the aorta depends on the severity of associated cardiac anomalies. The prognosis is good if the condition can be surgically corrected before it induces severe systemic hypertension or degenerative changes in the aorta.

Causes of Coarctation of the Aorta

Coarctation of the aorta may develop as a result of smooth-muscle spasm and constriction as the ductus arteriosus closes. Contractile tissue may reach inta the aortic wall, causing it to narrow.

Signs & Symptoms of Coarctation of the Aorta

Symptoms from coarctation depend on the severity of blood flow restriction. In severe cases, symptoms are present during infancy. In milder cases, symptoms may not develop until adolescence. Symptoms include decreased exercise performance, cold feet or legs, and shortness of breath. Other symptoms include:

• Chest pain
• Cold extremities
• Dizziness or fainting
• Hypertension (high blood pressure) with exercise
• Strong, throbbing headaches
• Fatigue

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 person 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.

Diagnostic Tests

Chest X-rays produce pictures by passing an X-ray beam through your body, which is absorbed in different amounts by body structures. A chest X-ray may show an enlarged heart or an indention in the aorta at the site of the coarctation.

Magnetic resonance imaging (MRI) - a diagnostic procedure that uses a combination of large magnets, radiofrequencies, and a computer to produce detailed images of organs and structures within the body.

Electrocardiography may initially show right ventricular hypertrophy and left-sided heart failure. If the coarctation isn't repaired, this test eventually shows left ventricular hypertrophy and a right axis deviation.

Echocardiography may disclose increased left ventricular muscle thickness, coexisting abnormalities, and the coarctation site.

Cardiac catheterization - During this procedure, your doctor inserts a thin flexible tube (catheter) into an artery or vein in your groin and threads it up to your heart. A dye is injected through the catheter to make your heart structures visible on X-ray pictures. Cardiac catheterization helps determine the severity of the aortic coarctation.

Treatment

For an infant with left-sided heart failure caused by coarctation of the aorta, treatment consists of medical management with prostaglandins, diuretics, and digoxin. Although most patients require surgery, the timing may be debatable. Most doctors recommend that surgery be done early. The procedure may involve end-to-end anastomosis or subclavian flap angioplasty. If the narrowed segment is long, the doctor may use a tubular graft, patch, or bypass conduit.

Prevention Tips

Coarctation of the aorta can't be prevented, because it's usually present at birth. However, if you or your child has a condition that increases the risk of aortic coarctation, such as Turner's syndrome, another heart defect, or a family history of congenital heart disease, discuss your risk of aortic coarctation with your family doctor.