Coarctation of the Aorta is a congenital heart defect that happens when there is a narrowing of the aorta as it makes the turn to supply the lower part of the body. The coarctation (narrowing) is usually located, just after the takeoff of the left subclavian artery (the branch to the left arm).

The left heart pump (Left Ventricle), then has to pump harder to force the blood to get through the narrowed area, so that the abdomen and legs can receive enough blood, with time the left ventricle muscle becomes thicker (hypertrophied).

The blood pressure gets higher, so as to push the blood across the narrowed area. As the blood squeezes through the obstructed area, it scatters under high pressure into strong jets; most of which move the blood forward but others hit hard against the walls of the aorta. Since so much moving energy is wasted in trying to force the blood through, the pressure beyond the narrowed area itself will be low.

In your child, this leads to high pressure in the arms and low pressure in the legs. High pressure in the arms would also be transmitted to high pressure to the arteries going to the brain. If this pressure goes untreated it may affect the arteries in the brain and cause stroke.

Symptoms:
Because of high blood pressure in the in the upper part of the body, your child may complain of headaches, nose bleeds, or blurred vision. And since the lower body is receiving blood at low pressure, the growth of the lower body be compromised, the lower body will look small compared with the upper body. The legs may be shorter than usual, cold, and when your child tries to play or run he may complain of pain in his calves (intermittent claudication). This is like muscle cramps but they are caused by a lack of blood supply to exercising muscles.

If the doctor finds that your child has high blood pressure it is very important to check that he does not have coarctation of the Aorta. If he complains of his calves hurting when he plays that also the pulses in his legs are normal and he does not have decreased pulses. It is very important to recognize and treat this condition very early, because if the blood pressure stays high for a long time, after correcting the defect the blood pressure may not return back to normal and your child may need medication for his entire life.