Coarctation of the aorta is one of the most common cardiac defects and is responsible for 5-8% of all congenital heart problems. Learn all about this abnormal cardiac disorder, including its types, causes, symptoms, diagnosis and treatment.
Coarctation of the aorta Definition
It is a congenital condition of the heart wherein the aorta – the major artery responsible for supplying oxygenated blood to the body, undergoes constriction or narrowing. It may occur in any region of the blood vessel. But it is most often observed beyond the point where the arteries, that supply blood to the upper body and head, branch off from the aorta. This causes the heart to pump blood harder through the narrowed aorta. The condition is generally found to arise along with other cardiac anomalies such as aortic stenosis or ventricular septal defect.
It is also known as “Aortic coarctation”.
Coarctation of the aorta Types
The condition is categorized into several types, which are as follows:
Picture 1 – Coarctation of the aorta
In this form, aortic constriction is adjacent to the ductus arteriosus (DA) – a blood vessel joining the pulmonary artery to the peak of the aorta. The condition is usually a severe consequence of intracardiac defect that develops in the fetus. This results in decreased blood flow through the left section of the heart. In this way, there is a defective development of the aorta.
The narrowing of the aorta occurs at the region where the ductus arteriosus closes completely.
This constriction is distal to the closing of the ductus arteriosus to form the ligamentum arteriosum – a small ligament attached to the superior pulmonary artery. An obstructed flow of blood to the lower section of the body can even occur in the presence of an open DA. It is commonly diagnosed in adults. During fetal life, the DA undergoes fibrosis when it starts extending into the aorta. Aortic coarctation then gradually develops upon birth.
Coarctation of the aorta Incidence
Around 5-8 in 100 infants with a congenital heart disorder may have a narrowed aorta. It is more common in males than in females.
Coarctation of the aorta in Adults
As aforementioned, this condition may develop at the neonatal stage. However, it is usually visible in adulthood and is normally more fatal.
Coarctation of the aorta Symptoms
In most cases, the narrowing is minor and might not give rise to any major symptoms. In certain cases, however, the aorta may be more constricted and cause acute strain on the left ventricle or lower chamber of the heart. The degree of narrowing may vary from one individual to another. In severe cases, the symptoms can be noticed within the first few weeks of life. In mild cases, the condition is generally visible in young children and adults. Some of the features include:
- Profuse sweating
- Shortness of breath after vigorous exercise
- Pale skin
- Lack of muscular strength
- High blood pressure
- Cold feet
- Swelling of the feet and legs
- Acute chest pain
- Leg cramps or numbness
- Poor development
- Frequent episodes of faint
Coarctation of the aorta Causes
Medical experts are still uncertain about the cause of this abnormal condition that generally begins before birth. It is often found to be associated with rib notching where the surface of the bones gets deformed. However, there are certain disorders that could be closely linked to this neonatal condition and includes:
The genetic disorder is marked by the presence of only one X chromosome instead of two. Due to this reason it may have a direct impact on the fetal heart, and cause Aortic coarctation.
It is a cerebrovascular disorder that causes localized dilation or ballooning of the blood vessels supplying the brain. The abnormal widening of the blood vessels may cause narrowing of the aorta.
The bacteria of the intestinal tract or urinary tract may sometimes cause infection of the inner surface of the valves of the heart. It is a common cause for a number of congenital heart defects, including aortic coarctation.
Congestive Heart Failure
The pumping efficiency of the heart is severely impaired that brings about inadequate supply of oxygenated blood to the body. The hypertension that results due to heart failure may lead to constriction of the major artery.
Thickening of the aorta wall, owing to the accumulation of fatty substances such as cholesterol, may constrict or block the flow of blood. Formation of multiple plaques within the artery is one of the most frequent causes of Aortic coarctation.
Inflammatory destruction of blood vessels may often damage the aorta that leads to blocked or narrowed arteries.
Coarctation of the aorta Diagnosis
Affected patients usually appear healthy and have mild symptoms of the condition. Serious cases are often diagnosed during infancy. High blood pressure in the arms as well as a loud heart murmur during a heartbeat can be observed in individuals with a narrowed aorta. A huge difference of blood pressure between the arms and legs is also an important manifestation of aortic constriction. Such a discrepancy results in weak or delayed pulse in the legs. Physicians typically go for the following diagnostic tests for the proper detection of the condition:
It shows an abnormally enlarged heart with an aortic malformation.
Cardiac computed tomography (CT)
It is a non-invasive procedure that generates detailed images of the heart with the help of an X-ray machine. Physicians can easily evaluate any abnormality in the blood vessels of the cardiac system that comprises of the pulmonary artery venae cavae and aorta.
It is a common ultrasound test that uses high-frequency sound waves transmitted through a device called transducer to produce images of the heart. The technique helps in detecting the exact location and severity of the aortic defect, especially in newborns. A host of other cardiac abnormalities associated with the condition can be observed using this procedure.
Cardiac magnetic resonance imaging (MRI)
It is a well-known non-invasive technique that is regularly used to get elaborate images of the major blood vessels of the heart. Complete analysis of the images may aid the health care providers to detect any sort of congenital abnormality.
Magnetic resonance angiography (MRA)
It consists of a group of techniques that are based on the MRI technology to get precise images of the arteries of the heart. It is done to detect and evaluate stenosis or abnormal narrowing of the blood vessels.
Affected individuals may have to go through this invasive imaging procedure for the diagnosis of the condition. Here, a catheter is inserted into a blood vessel in the arm, groin, or neck that is directly threaded to the aorta with the help of a thin wire. A special contrast dye is then injected through the catheter. With the aid of an X-ray machine the internal structures of the heart can be easily visualized for any major defects.
It is an advanced form of cardiac catheterization where the catheter is placed directly in the aorta while taking an X-ray.
Coarctation of the aorta Treatment
Arterial hypertension or high blood pressure could become a permanent problem if the aortic defect is not corrected in time. A varied range of treatment approaches are presently available that could repair the condition. Some of the options include:
Picture 2 – Coarctation of the aorta Image
A host of drugs, including prostaglandins and inotropic agents are administered to the patients for stabilization of the symptoms. This is done to cure any heart failure and to keep the ductus arteriosus open so that the blood can pass efficiently to the lower part of the body.
Several open-heart surgical interventions can be performed to correct Aortic coarction. Some of these include:
Left subclavian flap angioplasty
In this process, the subclavian artery in the left arm is isolated and divided distally. Next, it is opened in a longitudinal manner up to the aorta. The flap of the artery is later folded down over the region of the aortic narrowing and sutured. The constricted area can be expanded in this way.
Resection with end-to-end anastomosis
The distal arch of the aorta is incised at its inferior side while the lower aorta is cut along its lateral side and the two are surgically sutured together. In this way, the narrowed segment of the aorta undergoes complete resection or removal.
Bypass graft repair
In this procedure, a plastic tube is placed between the ends of the aorta to bypass the narrowed segment and restore normal blood flow.
The constricted region of the aorta is cut across and a small patch made of synthetic material is attached to it for widening the artery. This particular method is effective in curing severe cases of the condition, where a major segment of the aorta is involved.
Balloon angioplasty and stenting
It is used for treating Aortic coarctation as well as re-coarctation that might occur again after surgery. Surgical therapists insert a catheter into the artery in the groin and thread it up to the heart using a guidewire. A deflated balloon is then placed through the opening of the narrowed blood vessel. Sometimes it is advisable to use a stent, which is a mesh-covered hollow tube inserted to keep the deformed aorta wide open.
Coarctation of the aorta Life Expectancy
Aortic coarctation is one of the most common causes of premature deaths and is quite difficult to prevent. Long-term survival of the patients depends on factors like age as well as degree and duration of the condition. For those who are treated in late childhood or early adulthood can survive up to 38 years of age. Maternal mortality is also quite high during pregnancy.
The treatment of Coarctation of the aorta involves a proper monitoring, in addition to medical cure. Sufferers of this condition should avoid lifting heavy objects and prolonged exercises. There is a high chance of relapse after surgery. So, a regular follow-up is very important. If you are suffering from intense chest pain or shortness of breath, do not ignore the condition. Call your health care provider for immediate check-up and treatment.