coarctation of the aorta


Also found in: Dictionary, Thesaurus, Legal, Acronyms, Encyclopedia, Wikipedia.
Related to coarctation of the aorta: tetralogy of Fallot, patent ductus arteriosus

Coarctation of the Aorta

 

Definition

A defect that develops in the fetus in which there is a narrowing of the aortic arch, the main blood artery that delivers blood from the left ventricle of the heart to the rest of the body. Coarctation of the aorta is diagnosed in both newborns and adults. Approximately 10% of newborns with congenital heart disease have coarctation of the aorta.

Description

Blood leaves the heart by way of the left ventricle and is distributed to the body by arteries. The aortic arch is the first artery to carry blood as it leaves the heart. Other arteries to the head and arms branch off the aortic arch. A narrowing of the aorta at any spot produces resistance to the flow of blood. This causes high blood pressure before the narrowing and low pressure below the narrowing (downstream). Parts of the body supplied by arteries that branch off the aortic arch before the narrowing have high blood pressure, while most of the lower body does not receive enough blood supply. To compensate for this, the heart works harder, and the blood pressure rises.
Approximately half of all infants with coarctation of the aorta are diagnosed within the first two months of life. Frequently, there are other congenital cardiac complications present. Infants with Turner syndrome have a 45% rate of also having coarctation. There is evidence that some cases of coarctation may be inherited.

Causes and symptoms

In newborns with congenital heart disease, coarctation of the aorta develops while the baby is in the womb. Among the consequences of coarctation of the aorta is ventricular hypertrophy, an enlarging of the left ventricle in response to the increased back pressure of the blood and the demand for more blood by the body. Symptoms in infants include shortness of breath (dyspnea), difficulty in feeding, and poor weight gain. Older children usually don't have symptoms, but may display fatigue, shortness of breath, or a feeling of lameness in their legs.

Diagnosis

Infants usually have an abnormal "gallop" heart rhythm and may also have heart murmurs. Sometimes excessive arterial pulses can be seen in the carotid and suprasternal notch arteries, indicating increased pressure in these arteries, while the femoral pulse is weak or cannot be detected. The systolic pressure is higher in the arms than in the legs. Enlargement of the heart can be seen in x rays. Similar symptoms are seen in older children and adults. A 10 mm Hg (mercury) pressure difference between the upper and lower extremities is diagnostic for coarctation of the aorta. For some patients, the systolic pressure difference is observed only during exercise. Infants frequently have an abnormal electrocardiogram (ECG) that indicates that the right or both ventricles are enlarged, while in older children the ECG may be normal or show that the left ventricle is enlarged. The coarctation may be detected in echocardiographic examination.

Treatment

Drugs can be used to treat the hypertension and heart failure. Surgery is recommended for infants with other, associated cardiac defects and for those infants not responding to drug therapy. Surgery is indicated for infants that don't require immediate surgery, but who develop severe hypertension during the first several months of life. Patients are advised to avoid vigorous exercise prior to surgical correction of the coarctation. Recoarctation can occur in some patients, even if they have had surgery.

Prognosis

Approximately half of all infants diagnosed with coarctation of the aorta have no other cardiac defects and will respond well to medical management. Most of these children will eventually outgrow the condition after several years of life. Although their hypertension may increase for several months early in life, it will eventually decrease as the circulatory system develops. Surgery is required for infants that have severe coarctation of the aorta or have associated cardiac defects. The average life span of children who have coarctation of the aorta is 34 years of age. The most common complications for children who have not had surgery are hypertension, aortic rupture, intracranial bleeding, and congestive heart failure. Women who have an uncorrected coarctation of the aorta have a mortality rate of 10% during pregnancy and a 90% rate of complications.

Key terms

Dyspnea — Difficulty in breathing. Usually associated with heart or lung diseases.
Electrocardiogram — A graph of the heart's beating produced by an instrument that detects the electrical signals made by the heart.

Resources

Books

Alexander, R. W., R. C. Schlant, and V. Fuster, editors. The Heart. 9th ed. New York: McGraw-Hill, 1998.

coarctation of the aorta

a congenital cardiac anomaly characterized by a localized narrowing of the aorta. It results in increased pressure proximal to the defect and decreased pressure distal to it. The most common site of coarctation is just beyond the origin of the left subclavian artery from the aorta, resulting in high blood pressure in the upper extremities and head and low blood pressure in the lower extremities. Symptoms are directly related to the pressure changes created by the constriction. Clinical manifestations include dizziness, headaches, fainting, epistaxis, reduced or absent femoral pulses, and muscle cramps in the legs from tissue anoxia during increased exercise. Diagnosis is based on characteristic pressure changes in the upper and lower body and specific radiologicalnd echocardiographic findings, including notching of the lower ribs, left ventricular hypertrophy, and dilation of the aorta proximal to the stricture. A murmur may or may not be present. Surgical repair is recommended for minor defects because of the high incidence of untreated complications, including aortic rupture, hypertension, infective endocarditis, subarachnoid hemorrhage, and congestive heart failure.
enlarge picture
Coarction of the aorta

coarctation of the aorta

A localized congenital malformation resulting in narrowing of the aorta, often resulting in hypertension in adolescents and young adults. On physical assessment, it produces a delayed pulse in the femoral arteries relative to the pulse perceived at the radial arteries. Chest x-rays may show rib notching. Surgical correction of the obstruction may cure high blood pressure.
See also: coarctation

coarctation of the aorta

A congenital narrowing of a short section of the main artery of the body, the aorta, usually just beyond the point at which the arteries to the head and arms are given off. The pulses in the arms are much stronger than those in the legs.
References in periodicals archive ?
4) Coarctation of the aorta is treated with either percutaneous transluminal angioplasty with or without endovascular stent placement or surgery.
While this appearance is not limited to aortic coarctation, the finding of bilateral, symmetric rib notching in a patient >6 years of age, especially in association with an abnormal aortic contour as described above, is virtually diagnostic of coarctation of the aorta.
Endovascular stent implantation for coarctation of the aorta in children and young adults: intermediate follow-up results from Turkey.
Some individuals with coarctation of the aorta are known to have altered structure and function of both the coronary and other systemic arteries.
Cardiac catheterization and angiography revealed CBT, coarctation of the aorta and stenosis at the origin of left subclavian artery (Fig.
The most common associated lesions are arch abnormalities, specifically interrupted aortic arch, and coarctation of the aorta.
2]; 3) type I diabetes mellitus; 4) symptomatic orthostatic hypotension; 5) stenotic valvular heart disease; 6) acute coronary syndrome or cerebrovascular accident in the past 6 months; 7) planned cardiovascular intervention in the next 6 months; 8) primary pulmonary hypertension; 9) coarctation of the aorta, thyroid disorders, or Cushing's disease; and 9) alcohol or drug abuse.
While aortic wall abnormalities have been described in inherited connective tissue disorders such as Marfan syndrome and bicuspid aortic valve disease (52, 53), recent reports indicate similar aortic involvement in classical congenital heart disease entities such as coarctation of the aorta, tetralogy of Fallot and transposition of the great arteries; MRI is central in defining the problem (54).