Coarctation of the aorta

Alternative names

Aortic coarctation

Definition

Aortic coarctation is a birth defect in which the major artery from the heart (the aorta) is narrowed somewhere along its length, most commonly just past the point where the aorta and the subclavian artery meet.

Causes, incidence, and risk factors

Coarctation means narrowing; aortic coarctaction is a birth defect (congenital disorder) in which a portion of the aorta is narrowed. The aorta is the source blood vessel for many arteries, which supply the body with blood and nutrients.

Aortic coarctation causes low blood pressure and low blood flow in the arteries that branch off below the narrow spot; high blood pressure occurs in the arteries that branch off closer to the heart. As a result, aortic coarctation often leads to high blood pressure in the upper body and arms (or one arm) and low blood pressure in the lower body and legs.

Aortic coarctation is more common in some genetic conditions, such as Turner's syndrome, but it can also be associated with congenital abnormalities of the aortic valve, such as a bicuspid aortic valve.

Aortic coarctation occurs in approximately 1 out of 10,000 people. It is usually diagnosed in children or adults under 40.

Symptoms

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:

• dizziness or fainting
  
• pounding headache
  
• chest pain
  
• cold extremities
  
• nosebleed
  
• leg cramps with exercise
  
• hypertension (high blood pressure) with exercise
  

Note: There may be no symptoms.

Signs and tests

An examination reveals high blood pressure in the arms and low blood pressure in the legs, with a significant blood pressure difference between the arms and legs. The femoral (groin) pulse is weaker than the carotid (neck) pulse, or the femoral pulse may be totally absent.

Listening to the heart through a stethoscope reveals a murmur that is harsh and can be heard in the back. There may be signs of left-sided heart failure (especially in infants) or signs of aortic regurgitation.

Coarctation is often discovered during a newborn infant's first examination or during a well-baby exam. The health care provider will detect that the femoral pulses are absent or very weak. Taking the pulses in an infant is an important part of the examination as there may not be any other symptoms or findings until the child is older.