A PTA is a therapeutic interventional radiology procedure in which a stenosis ( a narrowing of an artery or vein) is opened using a balloon tipped catheter that is inflated to the normal size of the vessel. A stent is usually used to keep the vessel open. A stent is a small, metal, tube shaped scaffold. The stent is pre-mounted on a balloon catheter, and then the balloon is inflated at the site of the stenosis. The balloon is then deflated and removed, leaving the stent in place. A self-expanding stent may also be used. A more detailed explanation of stents follows under What is a stent?
Fatty deposits can accumulate in your blood vessels, reducing blood flow and in some cases, blocking it completely. These deposits may break off into pieces, forming "traveling clots" called emboli that can cause a heart attack or stroke. A PTA can open blocked vessels, restoring blood flow, and reducing these risks.
A stent is manufactured in one of two different configurations. The first type is called a balloon expandable stent. The stent is securely mounted on a balloon catheter and the catheter is advanced to the level of the narrowing. The balloon is then inflated which presses the stent against the vessel wall. The balloon is then deflated and the catheter removed. The second type is called a self-expanding stent. This stent is "spring-loaded" into a catheter and is secured to the catheter with an overlying sheath. The stent and catheter are advanced to the level of the narrowing, and once positioned, the sheath is pulled back allowing the stent to expand. The stent will expand to the normal size of the vessel. The catheter is then removed. The musculature of the vessel holds the stent in place. After a period of time, the vessel forms a cellular layer over the stent, so the stent basically becomes a part of the vessel. Because stents are made of stainless steel or metal alloys, they resist rust.
Angioplasty is often used as an alternative to by-pass surgery. You should consult
your physician to determine which form of treatment is best for you based on your
severity of disease. Ask your physician if you should consult an Interventional
Radiologist to see if you are a candidate for an angioplasty.
Several days prior to the procedure you will be given instructions from the Interventional Radiologist's office staff. You will need to have blood drawn at the hospital or a local clinic for testing. The staff will instruct you on how to prepare for the procedure including modification of your medications if necessary.
The procedure is performed in the interventional radiology suite. First, the nurse will give you a sedative through the intravenous line, which will be placed in your arm. You will feel relaxed and sleepy, but you will be awake throughout the procedure. The Interventional Radiologist will numb an area of your groin with a local anesthetic. He/she will then place a small, thin tube called a catheter into the femoral artery, which is a large artery in the groin. You will not feel any discomfort when the catheter is placed, but you may initially feel some slight pressure. The Interventional Radiologist will then advance the catheter to the area of the narrowed vessel. An angiogram, which an x-ray procedure that studies the arteries or veins, will then be performed to determine the location of the vessel stenosis. Because arteries and veins cannot be seen under x-ray, contrast media (x-ray dye) is used to "visualize" the vessels under x-ray.
Once the narrowed vessel has been identified, the Interventional Radiologist will then exchange the catheter for a stent delivery catheter or a balloon catheter. The Interventional Radiologist will direct the appropriate catheter to the narrowed area and either deploy the stent or inflate the balloon to open the vessel. The narrowing is usually caused by a build up of plaque in the vessel. The stent/ balloon pushes the plaque against the side of the vessel, thereby opening the vessel.
After the procedure, the catheter will be removed and the puncture site manually
compressed for about 20 minutes to prevent bleeding. After the procedure you will
need to lie in bed for 5 to 6 hours. You should plan to spend one night in the
hospital for observation. More specific post-procedure instructions will be given
to you prior to your discharge.