Renal Artery Stenting
What is renal artery stenting?
Renal artery stenting is a procedure to open the renal arteries – the large blood vessels that carry blood to the kidneys – when they have become blocked due to renal artery stenosis (narrowing of the renal artery). This is most often caused by atherosclerosis or fibrous disease of the arteries. When a renal artery is clogged, blood flow to the kidneys is affected. Stenting opens the blockage and restores normal blood flow.
The kidneys help to control the amount of salt and fluid in the body by filtering blood and making urine. When the blood cannot get to the kidneys to remove salt and water, fluid builds up in the body. In addition, the kidney releases a hormone called renin that promotes the retention of salt and water and also causes the blood vessels in the body to become more rigid. Together, this results in a type of high blood pressure called renovascular hypertension. High blood pressure puts extra strain on the heart and other organs. Renovascular hypertension can also cause kidney failure, which can lead to dialysis or a kidney transplant.
How will I know if I need renal artery stenting?
Your doctor will use certain tests to see if you need renal artery stenting. Among these tests are the following:
- Angiography: During this test, a catheter is inserted through the groin into the aorta, the main artery in the body. The catheter is advanced to the renal arteries and a dye is released. A series of X-rays is taken to see how well the blood is flowing through the arteries.
- Magnetic resonance angiography: This test is similar to regular magnetic resonance imaging, which uses a large magnet to create images of the inside of the body. In magnetic resonance angiography, a contrast dye is injected into the blood so that the area that is being imaged stands out.
- Computed tomography angiography: Computed tomography uses a series of cross-sectional X-rays to build a three-dimensional image of the inside of the body. Again, this test makes use of a contrast dye to highlight the renal arteries.
- Duplex Doppler ultrasonography: This test uses sound waves to measure the size of the narrowed area and the speed of the blood flow within the renal arteries.
Will renal artery stenting cure renal artery stenosis?
In most cases, the angioplasty and stenting procedure does not cure renal artery stenosis, but it can slow the progress. Many patients with renovascular hypertension continue to take blood pressure medicine.