What is Coarctation of the Aorta (Narrowing of the Aorta)?
Coarctation of the aorta is a condition where the aorta, the main artery that carries blood from the heart to the rest of the body, becomes narrower. This usually happens just past the left subclavian artery, but can also occur in other parts of the aorta including the thoracic or abdominal aorta. The narrowing increases the blood pressure in the upper body, which can cause high blood pressure in the arms. If not treated, coarctation can lead to early onset heart disease, problems with the ventricles in the heart, ballooning or tearing of the aorta, and issues with the blood vessels in the brain by the time a patient reaches their 30s or 40s.
What Causes Coarctation of the Aorta (Narrowing of the Aorta)?
The most common cause of a condition called coarctation of the aorta is the narrowing of the aorta near an area known as the patent ductus arteriosus or ductal ligamentum. It’s believed that the tissue in this area can tighten the nearby part of the aorta, which shrinks the inner tube of the aorta.
Coarctation can also be more complicated, showing up as underdeveloped aortic arch or along with other problems related to the left side of the heart, like mitral stenosis, aortic stenosis, or underdeveloped left heart syndrome. Coarctation around the middle of the chest can happen with mid-aortic syndromes.
Over time, the body adapts by forming detours around the narrowed segment of the aorta.
Risk Factors and Frequency for Coarctation of the Aorta (Narrowing of the Aorta)
Coarctation, a type of congenital heart disease, affects between 6% to 8% of people diagnosed with this condition, equivalent to around 0.06% to 0.08% of the general population. It’s responsible for a portion of children who have high blood pressure. People with Turner syndrome, which is a condition where a female has only one X chromosome, have a higher chance of developing left-sided heart diseases like coarctation. So, women diagnosed with coarctation are usually recommended to take karyotype tests, which help in diagnosing Turner syndrome. The condition often goes hand in hand with a bicuspid aortic valve – a heart valve with two leaflets instead of three.
It’s important to note that if a close relative, such as a sibling or parent, has been diagnosed with a left-sided heart disease blocking blood flow, the risk of coarctation and other heart conditions increases by ten times.
Signs and Symptoms of Coarctation of the Aorta (Narrowing of the Aorta)
Coarctation of the aorta is a heart condition that can show up in different ways, depending on a person’s age. In newborns, symptoms may include difficulty in feeding, symptoms of shock like poor blood circulation, a distinctive sound in the heartbeat known as a gallop, and a heart murmur related to leakage in the mitral valve. People with severe coarctation could have issues feeling the pulse in their thigh and top of the foot areas. There’s also oftentimes a noticeable delay in pulse between the arm and the thigh.
Hypertension or high blood pressure in the upper body is a common symptom, so any child or young adult being checked for this condition should have their blood pressure measured in all four limbs. Older kids might have a particular kind of heart murmur that lasts into the diastolic phase (the period when the heart is relaxing and filling with blood) and can be heard near the lower part of the left shoulder blade. This murmur might suggest blood flowing over the coarcted (narrowed) area or through enlarged side branches of the aorta.
There can also be a clicking sound as well as a heart murmur during systole (the period when the heart is contracting and pumping out blood) that can be heard near the top of the breast bone on the left side. These are common findings in people with a bicuspid aortic valve (a condition where the valve between the left ventricle of the heart and the aorta has only two leaflets or cusps instead of the normal three).
While rare, adults can also suddenly present with either a rupture of the main blood vessel exiting the heart (aortic dissection) or a stroke due to an undiagnosed coarctation of the aorta.
Testing for Coarctation of the Aorta (Narrowing of the Aorta)
In a patient suffering from a condition called coarctation, the EKG (a test that checks the heart’s electrical activity) may show raised levels of energy in the heart’s exterior leads. This suggests that the left side of the heart is larger than normal. An echocardiogram (a type of ultrasound used to examine the heart) can back this up as it may also show that the left part of the heart is larger than it should be.
In newborn babies, the performance of the left ventricle in the heart might be reduced. The heart may also have issues with the mitral valve, which might not close properly and can leak. The left atrium, one of the heart’s compartments, can also become larger because there is high pressure inside it.
The echocardiogram could also show a narrowing in the part of the aorta that bends closest to the left subclavian artery. Speeds captured with Doppler ultrasound (a test that uses sound waves to capture images of blood flowing through the vessels) could speed up in this area. But it might also seem that the aorta is underdeveloped or atypically small. The pulses in the abdominal aorta (the large blood vessel that supplies blood to the abdomen, pelvis, and legs) are lower, with blood flow continuing into the heart’s resting phase.
CT scans (X-ray scans that take many images which are combined to create detailed pictures of your body) and MRI (scans that use strong magnetic fields and radio waves to produce detailed images of the inside of the body) can provide a detailed look at the aorta, and are especially good for showing the details of the aortic arch (a bend in the aorta) before and after treatment.
Treatment Options for Coarctation of the Aorta (Narrowing of the Aorta)
In a newborn who shows signs of shock, the first step should be to stabilize their heart and lung function. One method to temporarily help this situation involves using a drug called Prostaglandin E1, which opens a temporary blood vessel called the ductus arteriosus and can also relax the tightened area in the aorta. Often, this medical support alone can improve the function of the heart.
However, the treatment for this condition, called coarctation of the aorta, is to remove the narrowed part. This can be done either with a surgical procedure or through a method using a catheter (a thin tube inserted into blood vessels). The surgical method involves cutting out the narrowed portion and then stitching the normal parts of the aorta back together. The catheter method uses a balloon and a small wire tube called a stent to widen the narrowed area.
Mostly, the surgical method is preferred for newborns and small children, while the catheter method can be used in adolescents and adults. Balloon widening has been done in newborns and children as well. However, no method provides a complete cure for this condition.
There’s around a 10% chance of the aorta narrowing again in newborns after the surgical treatment. If that happens, a balloon treatment is recommended. The balloon treatment method actually increases the risk of aorta bulging or aneurysm over time. And even after treatment, there is a higher chance of developing high blood pressure. There’s also an increased risk of bulging blood vessels in the brain in patients with this condition, whether they have been treated or not.
These risks are why patients diagnosed with coarctation of the aorta should continue to see a heart disease specialist who specializes in congenital (birth) conditions throughout their lives.
What else can Coarctation of the Aorta (Narrowing of the Aorta) be?
The conditions mentioned include:
- Aortic dissection: a serious condition where the main artery leading from the heart splits into two.
- Coarctation of the aorta: a narrowing of the aorta that can increase blood pressure.
- Myocarditis: an inflammation of the heart muscle.
- Pediatric hypoplastic left heart syndrome: a birth defect that affects the normal blood flow through the heart.
- Pediatric sepsis: a life-threatening condition where a child’s body reacts severely to an infection, which can lead to tissue damage and organ failure.
- Peripheral arterial occlusive disease: a condition where the arteries that supply blood to the limbs are blocked.
These are all significant health issues that require medical attention.
What to expect with Coarctation of the Aorta (Narrowing of the Aorta)
Coarctation of the aorta – a narrowing of the large blood vessel that delivers oxygen-rich blood from the heart to the body – is a lifelong condition with a cautious long-term prognosis. Regular medical check-ups are critical as the narrowing can recur and high blood pressure can persist.
People with this condition also require a safeguard against a heart infection called endocarditis if they’re undergoing any invasive procedure. As for short-term outcomes, those who can’t control their high blood pressure generally fare worse than those without high blood pressure.
Data for long-term outcomes are limited because many patients lose contact with healthcare providers. However, their survival rates are generally lower than the average population. People who don’t get the coarctation fixed are typically not expected to live past the age of 50.
Possible Complications When Diagnosed with Coarctation of the Aorta (Narrowing of the Aorta)
Common Complications:
- Recurrent coarctation – a repeated narrowing of the aorta
- Aortic aneurysm – an enlarged area in the aorta
- Hypertension – high blood pressure
- Cerebral aneurysm – a bulging, weakened area in the wall of an artery in the brain
- Cardiomyopathy – a disease of the heart muscle
- Paralysis – the risk of inability to move post surgery can be decreased by cooling the body to 34-35 °C and reducing the duration of aortic obstruction
- Post coarctectomy syndrome – a set of symptoms occurring after surgery to correct aortic coarctation
Recovery from Coarctation of the Aorta (Narrowing of the Aorta)
After the coarctation is fixed, it’s essential to keep an eye on the patient’s blood pressure and provide treatment if it’s too high.
Preventing Coarctation of the Aorta (Narrowing of the Aorta)
There’s no known way to prevent coarctation, but if you suspect you might have it, it’s advised that you see a cardiologist promptly for an echocardiogram. This is a type of heart scan that can help in detecting this condition early on.
To keep your heart healthy, it’s beneficial to get regular exercise, abstain from smoking, and maintain a healthy weight. These lifestyle choices not only promote your overall health but can also help manage coarctation symptoms and improve your heart function.
