Aortic Coarctation (Coarctation of the Aorta)

What happens in coarctation of the aorta

The aorta leaves the heart, arches over the top and runs down through the chest and abdomen. Coarctation is usually a narrowing in the upper chest, just after the branches that supply the head and arms and close to where a fetal blood vessel (the ductus arteriosus) joins.

The heart must pump harder to push blood through the narrow segment. As a result:

• blood pressure is high above the narrowing, in the arms and head
• blood pressure and flow are low below the narrowing, in the legs and lower body
• the left side of the heart thickens over time and can fail

Before birth, the ductus arteriosus bypasses the aorta, so the baby is fine in the womb. After birth, the ductus normally closes within days. If the coarctation is severe, closure of the ductus suddenly cuts off blood flow to the lower body, causing collapse. In milder cases, the body grows extra blood vessels (collaterals) around the narrowing, so problems may not appear for years.

Associated conditions

Coarctation often occurs with other heart problems:

• Bicuspid aortic valve (an aortic valve with two leaflets instead of three) in roughly half or more of people with coarctation. See aortic valve disease.
• Ventricular septal defect and patent ductus arteriosus.
• Brain aneurysms, which are more common in people with coarctation.
• Turner syndrome: a chromosome condition in girls, of whom a significant minority have coarctation.

Symptoms

In newborns and infants

• Poor feeding, tiring or sweating during feeds
• Fast or labored breathing
• Pale, gray or blotchy skin, and cold legs
• Irritability or unusual sleepiness
• Weak or absent pulses in the groin
• Poor weight gain

Severe cases cause shock and heart failure as the ductus closes, often in the first 1 to 2 weeks.

In older children and adults

Many have no symptoms. Possible signs include:

• High blood pressure in the arms, often found at a routine checkup
• Headaches and nosebleeds
• Leg cramps, weakness or tiredness with exercise
• Cold feet
• Chest pain or breathlessness

Diagnosis

• Examination: comparing pulses and blood pressure in the arms and legs. A blood pressure that is higher in the arms than the legs, or groin pulses that are weak or delayed compared with the wrist pulse, are classic signs. A heart murmur may be heard.
• Newborn pulse oximetry screening: detects some critical heart defects, though coarctation can be missed.
• Echocardiogram: ultrasound of the heart shows the narrowing and associated defects. It is the main test in babies and children.
• Prenatal ultrasound: coarctation is sometimes suspected before birth, though it is hard to confirm until after the ductus closes.
• ECG and chest X-ray: may show heart strain, and in adults, notching of the ribs from enlarged collateral vessels.
• CT or MRI angiography: detailed images of the aorta, used in older children and adults and for planning treatment.

Treatment

Emergency care in newborns

Babies who are critically ill receive a medicine called prostaglandin E1 through a vein to reopen the ductus arteriosus and restore blood flow to the lower body, followed by surgery.

Surgical repair

Surgery is the usual treatment in babies and young children. The narrow segment is removed and the ends are joined (resection with end-to-end anastomosis), or the aorta is widened with a patch or graft.

Balloon angioplasty and stent

A catheter is passed through a blood vessel in the groin to the narrowing, where a balloon widens it and a metal stent holds it open. This is commonly used in older children and adults, and to treat re-narrowing after previous surgery.

Blood pressure management

Many people continue to have high blood pressure after a successful repair and need blood pressure medicines.

Complications

• High blood pressure, even after repair
• Re-narrowing (recoarctation)
• Aneurysm at the repair site
• Aortic dissection (a tear in the aorta wall)
• Early coronary artery disease, stroke and heart failure
• Problems with an associated bicuspid aortic valve, such as stenosis or leakage

Outlook and living with coarctation

With timely repair, most children grow up to lead active lives. However, coarctation is a lifelong condition. Adults should be followed by a cardiologist with expertise in adult congenital heart disease, with regular blood pressure checks (including checking for differences between arms and legs) and periodic imaging of the aorta. Many people can exercise normally, though very heavy weightlifting may be restricted if blood pressure is high or the aorta is enlarged. Pregnancy is often possible but should be planned with a cardiologist and obstetrician.

Frequently asked questions

What is coarctation of the aorta?

Coarctation of the aorta is a narrowing of the body's main artery, present from birth. It forces the heart to pump harder and causes high blood pressure in the arms and low blood flow to the legs. Severe cases cause heart failure in newborns, while milder cases may be found later as high blood pressure.

What are the symptoms of coarctation of the aorta in adults?

Many adults have no symptoms. The most common sign is high blood pressure in the arms, with weaker pulses and lower pressure in the legs. Others include headaches, nosebleeds, leg cramps or tiredness with exercise and cold feet. A doctor can check by comparing arm and leg pulses.

How is coarctation of the aorta treated?

It is treated by surgically removing or widening the narrow segment, or by balloon angioplasty with a stent through a catheter. Newborns who are critically ill first receive medicine to keep a fetal blood vessel open. Many people also need blood pressure medicine and lifelong follow-up.

Can coarctation of the aorta come back after repair?

Yes. Re-narrowing (recoarctation) can happen, especially after repair in infancy. It is usually treated with balloon angioplasty and a stent. Regular checkups with blood pressure measurement in the arms and legs and periodic imaging help detect it early.

Is coarctation of the aorta genetic?

It is usually not inherited in a simple pattern, but it does run in some families and is linked to conditions such as Turner syndrome. Parents with a congenital heart defect have a higher chance of having a child with one, so fetal echocardiography may be offered in future pregnancies.