Aortic Coarctation

Signs and Symptoms

Aortic coarctation is a narrowing of part of the aorta, the artery that sends oxygenated blood from the heart to the rest of the body. Many people with this condition will not have symptoms until later in life. However, it can lead to hypertension resulting in stroke, congestive heart failure and complications of coronary artery disease.

When the aorta is too narrow, it restricts blood flow to the lower part of the body and increases blood pressure above the narrowing. This means your heart has to work harder to circulate blood to the rest of the body. As a result of the increased work, the heart wall initially thickens, a condition called hypertrophy. If the coarctation is not corrected, heart failure may develop. One of the symptoms of congestive heart failure is breathlessness. If you were born with aortic coarctation, you may have other heart abnormalities such as deformed aortic valves, patent ductus arteriosus or ventricular septal defect.

High blood pressure above the narrowing also can result in high blood pressure in the arteries that branch out from the aorta, including those in the arms and brain. This may increase the risk of a stroke.

Below the narrowing, the blood pressure may be too low and cause problems feeding enough blood into organs such as the kidneys.

Symptoms of aortic coarctation include:

• Difficulty breathing with exertion, called exertional dyspnea
• Headaches
• Nose bleeds, called epistaxis
• Leg fatigue and cramps

In untreated patients younger than 30 years old, aortic rupture and cerebral hemorrhage are the most common complications. After age 40, the incidence of congestive heart failure increases.

Diagnosis

If a person doesn't have severe symptoms at birth, the aortic coarctation may go unnoticed until adulthood. It is most commonly discovered in adults between the ages of 15 and 40, often because the doctor notices a heart murmur in a patient with high blood pressure. Rarely, a patient may come for emergency treatment because of aortic rupture, infection or cerebral bleeding.

Tests to determine whether a coarctation is present include:

• Blood pressure is checked to see whether there is lower blood pressure or reduced pulse in the legs compared to the arms
• Electrocardiogram (EKG or ECG), which records the heart's electrical activity
• Chest X-ray to see the heart's size
• Echocardiogram, which is an ultrasound examination of the heart
• Magnetic resonance imaging (MRI) to produce pictures of the heart

In addition, your doctor may use a cardiac catheterization procedure to inject a dye into the heart and to see on a moving picture X-ray how the heart and aorta are functioning.

Treatment

In the past, coarctation repair always involved heart surgery through an incision in the side of the chest that required five to seven days in the hospital for recovery. Now it is often possible to correct coarctation without surgery in a procedure called a cardiac catheterization.

Cardiac Catheterization

The heart catheterization consists of placing a long, thin, hollow plastic tube, called a catheter, into the blood vessel in the groin and passing it through vessels into the heart's chambers. The catheter is used to gather blood samples, take pressure measurements and inject dye for X-ray movies. Modern imaging technology allows doctors to see where the catheter is going and how the heart is functioning.

The diameter at the site of aortic narrowing is measured so that the proper size stent, an expandable slotted metal tube, can be selected. Sometimes, more than one stent will be needed for complete repair. If the narrowing is too close to the head and neck vessels, stent repair may not be possible. Surgical repair would then be necessary and would be scheduled for another time.

After an appropriate stent has been selected, it is placed over a deflated balloon at the catheter's tip. When the balloon reaches the site of the narrowing, it is expanded to widen the artery. The stent is left in place to support the newly widened artery walls and the catheter and balloon are withdrawn.

The procedure is safe and effective with immediate complete repair in over 98 percent of patients. Complications during the procedure are rare and almost all can be treated immediately. These include blood loss requiring a transfusion, allergic reaction to X-ray dye requiring medication, aneurysm and improper stent position requiring retrieval by catheter or surgery. There is a small risk of blockage of the groin vessels used for catheterization, which ordinarily responds to medication. Complications after the procedure, such as breakage, movement or infection of the stent, are extremely rare and occur in less than 1 percent of patients. In less than 5 percent of patients, an aneurysm or widening at the stent site may develop.

The catheterization and stent placement take approximately three to four hours. Patients are admitted to the hospital the morning of the procedure and discharged the following morning. Most often, patients are treated with a drug that blocks platelet function, such as clopidigrel, for a period of time after the procedure.

After treatment, follow-up will be necessary for the rest of your life. This will include taking antibiotics before dental or surgical procedures, regular magnetic resonance imaging (MRI) exams and perhaps subsequent surgery. Women should consult with a cardiologist before becoming pregnant to determine any risk factors.