How does coarctation of the aorta cause hypertension? How common is coarctation of the aorta? Let’s find out about the coarctation of aorta diagnosis and treatment!
Table of Contents
Coarctation Of Aorta Definition
Coarctation of aorta meaning – What is coarctation of aorta? Coarctation of the aorta is narrowing the aortic arch in one spot, just below where the left subclavian artery starts. If the stenosis is severe, collateral circulation develops around the coarctation site through the intercostal arteries and the branches of the subclavian arteries. This can lower the trans-coarctation gradient by letting blood flow around the blockage.
Coarctation Of Aorta Causes
What causes coarctation of aorta? It is not clear what causes coarctation of the aorta. It is usually a heart problem that is present at birth (congenital heart defect).
Coarctation is a cause of secondary hypertension, so young people with high blood pressure should think about it (BP). But the renin-angiotensin system is often wrong, leading to high blood pressure even after coarctation repair. In addition, there is a bicuspid valve in about 50–80% of cases, and the number of cerebral berry aneurysms is on the rise.
Significant native or recurrent aortic coarctation has been described as upper and lower extremity Peak-to-peak gradient greater than 20 mm Hg or mean Doppler systolic gradient greater than 20 mm Hg: upper extremity/lower extremity gradient greater than 10 mm Hg or mean Doppler gradient greater than 10 mm Hg when there is either decreased left ventricular (LV) systolic function or aortic regurgitation (AR); or upper extremity/lower extremity gradient greater than 10 mm Hg or mean Doppler.
This should be paired with anatomic proof of coarctation of the aorta, usually found through advanced imaging (cardiac magnetic resonance, CT angiography). The ESC guidelines have changed the severity criteria and say that stenting is necessary if the patient has normal blood pressure but a peak gradient of more than 20 mm Hg (class IIa) or if the stenosis by angiography is more than 50%. (class IIb).
Coarctation Of Aorta Diagnosis
- Systemic hypertension is the most common symptom.
- Echocardiography and Doppler are used to diagnose; a peak gradient of >20 mm Hg may be important if collaterals around the coarctation lower the gradient even though the coarctation severely blocks blood flow.
- 50–80% of patients also have a bicuspid aortic valve.
- Compared to the brachial artery, the pulse in the femoral artery is late.
- The systolic pressure is higher in the upper limbs than in the lower limbs, but the diastolic pressures are the same.
Coarctation Of Aorta Symptoms
Signs and symptoms of coarctation of aorta: If heart failure doesn’t happen when the baby is young, there are usually no signs until the high blood pressure causes LV failure. Even though it is rare, a brain bleed can happen.
Magnetic resonance angiography or CT angiography can find intracranial aneurysms in about 10% of people with coarctation of the aorta. A risk factor is getting older. In the neck and suprasternal notch, you can see strong arterial pulses. The pressure in the arms is too high, but the pressure in the legs is normal or low.
Exercise makes this difference even bigger. Compared to the brachial or radial pulse, the femoral pulse is weak and takes longer to show up. When large collaterals are present, a constant murmur may be heard high and in the middle of the back or over the left front of the chest. This is a sign that the coarctation is severe.
The coarctation can cause systolic ejection murmurs in the upper left lung field near the spine and the upper left lung field near the spine. In addition, due to a bicuspid aortic valve, there may be an aortic regurgitation or stenosis murmur. Turner syndrome is a chromosomal abnormality (XO) linked to coarctation. People with Turner syndrome may have a webbed neck.
Coarctation of Aorta Radiology
Most of the time, the ECG shows LV hypertrophy (LVH). Due to enlarged collateral intercostal arteries, an x-ray may show that the lower part of the ribs is scalloped or notched. The left subclavian artery may be dilated, and the aorta may be dilated after stenosis. The left ventricle (LV) may also be bigger. On a PA chest x-ray, the area of coarctation and the post stenotic dilation of the descending aorta can cause a “3” sign along the aortic shadow (the notch in the “3” representing the area of coarctation)
Coarctation 0f Aorta Diagnostic Evaluation
Echocardiography/Doppler can usually tell what’s wrong and may give more proof of a bicuspid aortic valve. Both MRI and CT are great ways to get good pictures of the anatomy of coarctation, and one or the other should always be done to define the anatomy of a coarctation. MRI, echocardiography, and Doppler can also estimate the gradient across the lesion. A cardiac catheterization gives clear information about the gradient and is needed if percutaneous stenting is to be considered.
Coarctation Of Aorta Treatment and Management at Home
Treatment of coarctation of the aorta – What is the best treatment for coarctation?
Cardiac failure is common in babies and older people who don’t get treatment for severe coarctation. Patients with a shown peak gradient of more than 20 mm Hg should be considered for intervention, especially if there is evidence of collateral blood vessels.
As was said above, the ESC guidelines also use the severity of stenosis (greater than 50%) to define severe coarctation. Many people with severe coarctation who don’t get treatment die before they turn 50 from high blood pressure, a ruptured aorta, infected endarteritis, or bleeding in the brain. Aortic dissection is also happening more often. Because the placenta flow can’t be supported, coarctation may be hard to handle during pregnancy.
The risk of dying during resection of the coarctation site is between 1% and 4%, and there is also a chance of spinal cord injury. Endovascular stenting is the best percutaneous interventional procedure. Self-expanding and balloon-expandable covered stents are better than bare metal stents when anatomically possible. The FDA has approved these stents with a cover.
Most repairs for adults with coarctation are done through the skin. If not, surgical resection should be done, usually with end-to-end anastomosis.
About 25% to 50% of people who have surgery to fix their high blood pressure are still hypertensive years later. This is because the renin-angiotensin system, endothelial dysfunction, aortic stiffness, altered arch morphology, and increased ventricular stiffness all change permanently. Whether the repair was done with balloon dilatation, a stent, or surgery may affect whether or not hypertension develops. If the coarctation stenosis comes back after treatment, long-term follow-up is needed.
I hope you understand the coarctation of aorta diagnosis and treatment guidelines.