Synonyms in the broadest sense
Narrowing of the aorta, constriction of the aorta, coarctatio aortae English: stenosis of the aortic isthmus, coarctation of the aorta, aortic coarctation
Aortic isthmus stenosis is a narrowing of the aorta. It is narrowed after it emerges from the heart and after the branch of the artery that supplies the upper half of the body. In this area the aorta makes an arc, which is why it is called the aortic arch.
The different forms
There is a childlike and an adult form of vascular change of the aorta. In the infantile form, aortic isthmus stenosis is present from birth and there are usually other heart defects. About 7% of all congenital heart defects are aortic coarctation.
Adults (adult form) with a narrowed aorta have acquired this vascular stenosis, i.e. it has not existed since birth. Accompanying heart diseases are rare in this form of aortic coarctation. At 6 to 10%, aortic isthmus stenosis is one of the most common heart defects in newborns.
There are various forms of aortic coarctation which differ anatomically. Often, the vascular constriction lies before the ductus arteriosus (a structure from the embryonic blood circulation) enters the aorta. This form is called preductal aortic isthmus stenosis.
More rarely, the stenosis lies behind the point where the aterior duct enters the aorta. Then it is called postductal aortic coarctation. If a newborn infant suffers from preductal isthmus stenosis, a life-threatening situation can arise because the ductus arteriosus closes soon after birth.
The ductus arteriosus supplies the lower half of the body with blood in the unborn child. In the case of preductal isthmus stenosis, it is therefore important to give the drug prostaglandin in order to reopen the ductus arterious and keep it open. Depending on how pronounced the stenosis is, newborns may already show signs of heart failure (cardiac insufficiency) before the operation: increased sweating, accelerated breathing, weakness in drinking and failure to thrive. If a newborn is born with a pronounced aortic coarctation, the child may show shock-like deterioration. In newborns and infants it is therefore important to detect aortic coarctation as early as possible and to initiate a relieving therapy.
High blood pressure can occur with given changes in the aorta. Normally the blood pressure in the legs or the lower half of the body is 30-40 mmHg higher than in the arms or the upper half of the body, but the opposite is true for aortic isthmus stenosis. The narrowing of the aorta leads to an inverse blood pressure difference between the arms and legs.
The blood pressure in the vascular system is increased in the section before the constriction and decreased after the constriction. Aortic isthmus stenosis is also called hypertension of the upper extremities with the symptoms headache, dizziness, nosebleed (also nosebleed can occur in connection with headache) and a feeling of throbbing in the head area. The blood pressure values of the lower half of the body are lowered (hypotension) and there may be weakness in the legs up to a reduced blood supply in the legs.
A difference in blood pressure can be a symptom of aortic isthmus stenosis. This means that there is a marked difference in blood pressure between the arms and the legs. This pulse deficit is the main symptom of aortic coarctation and is noticeable to those affected, for example by having warm hands but cold feet.