by Maria Adams, MS, MPH
Anatomy and Physiology
Your heart pumps blood that is carried by arteries to organs and tissues throughout your body. Your veins return the blood back to your heart. With few exceptions, arterial blood is oxygen-rich, while venous blood is oxygen-depleted.
Your organs and tissues need a steady supply of oxygen and other nutrients delivered through the blood to function properly. As your blood circulates it also absorbs nutrients from food in the intestines, regulates temperature, and removes waste products.
Reasons for Procedure
Fatty deposits, called atherosclerotic plaques, can build up inside your arteries, narrowing the passageway and interfering with blood flow. This arterial blockage is called stenosis. This condition also increases the risk of blood clots forming and getting stuck around areas of plaque build-up.
Plaque build-up can occur in anyone. It's a slow process that tends to progress as we age. However, certain conditions can put you at greater risk for atherosclerosis, including: kidney disease involving dialysis, diabetes, high blood cholesterol, high blood pressure, obesity.
Additionally, certain lifestyle factors, such as cigarette smoking, physical inactivity, and a diet high in saturated fat, may increase your risk of atherosclerosis.
Atherosclerosis can affect large and medium-sized arteries throughout the body. The most commonly involved are the: carotid arteries in the neck, coronary arteries around the heart, abdominal aorta, renal arteries to the kidney, Iliac arteries in the groin, femoral and popliteal arteries in the leg.
Insufficient blood flow to a tissue generally causes pain, particularly at times when the tissue requires extra oxygen. Therefore, people with stenosis in the arteries supplying the legs may experience pain and cramping during exercise, but not at rest. Low blood flow to the legs over a long period of time may lead to persistent pain, cold feet, open sores, and if blood flow is completely interrupted, gangrene.
Some of the tests your doctor may perform to diagnose stenosis in your arteries include: comparison of blood pressure in your arms and legs, x-ray angiography, which uses a special dye injected into the blood stream to produce x-ray images of your arteries, magnetic resonance angiography, or MRA, which uses a powerful magnet, radio waves, and computers to produce images of your arteries, doppler study, which uses sound waves to measure blood flow through your arteries.
An angioplasty is only done when less invasive treatment options have failed to improve your condition. The first line of treatment should always consist of lifestyle changes, such as: following a low-calorie, low-fat diet, participating in a progressive exercise program and/or quitting smoking.
In addition, medications are often prescribed that can decrease pain during exercise or lower the risk of further complications. These may include drugs that: lower blood pressure, improve cholesterol levels, dilate, or expand, your arteries, make your blood less likely to clot.
In severe cases of stenosis, and in people who have not responded to lifestyle changes or medications, an invasive procedure may become necessary. The three most common procedures to treat atherosclerotic stenosis are: percutaneous transluminal angioplasty or balloon angioplasty, bypass surgery, endarterectomy, most commonly done for blockages in the carotid arteries leading to the brain.
Percutaneous transluminal angioplasty, or PTA, involves threading a catheter equipped with a tiny balloon through an artery to the site of a stenosis. When the balloon is inflated, the plaque is pushed aside and the narrowed artery is widened, allowing more blood to flow through. Although this procedure is most commonly used to treat blockages in the coronary arteries, it is also often performed on other arteries prone to atherosclerosis, particularly those leading to the legs.
In a bypass graft, a surgeon restores blood flow by using a vein, or an artificial vessel, to construct an alternate route around the narrowing in an artery. In an endarterectomy, a surgeon directly restores blood flow inside an artery by opening it up and removing the plaque inside.
In the days leading up to your procedure: Arrange for a ride to and from the hospital and for some help at home afterwards. The night before, eat a light meal, and do not eat or drink anything after midnight. If you regularly take medications, herbs, or dietary supplements, your doctor may ask you to temporarily discontinue them. Do not start taking any new medications, herbs, or dietary supplements before consulting your doctor. You may be asked to shower using special antibacterial soap the morning of your procedure.
Most non-coronary angioplasties take 1-2 hours. You will remain awake for the procedure, but may be offered a sedative to help you relax. To begin the procedure, you will be placed on a table equipped with a fluoroscope. A fluoroscope is capable of taking x-ray images of many parts of the body from multiple angles.
Your doctor will numb your skin around where the catheter is to be inserted. Since the arteries of the leg are most easily accessed, the femoral artery in the groin serves as the insertion site in most cases. Your doctor will initially gain access to the artery by inserting a hollow needle through which the balloon-tipped catheter is passed.
Watching on the fluoroscopy screen, your doctor will gently advance the catheter until it is positioned in the artery being treated and inject a special dye. This dye allows the fluoroscope to take x-ray images, called angiograms, which let your doctor identify the exact location of the blockages.
Next, your doctor will move the catheter until the deflated balloon at its tip is positioned at the site of the stenosis. Then, by rapidly inflating and deflating the balloon, your doctor will gently push the plaque and vessel wall out, partially reestablishing blood flow. This procedure may be repeated for any additional blockages.
In some cases, your doctor may place a stent, which is a wire mesh that remains in the artery to hold it open. To perform this procedure, your doctor will place a collapsed stent over the deflated balloon on the tip of the catheter. When the balloon is inflated, the stent expands and locks into place.
At the end of the procedure, your doctor will remove the catheter through the original insertion site.
Risks and Benefits
Possible complications of PTA include: bleeding at the point of the catheter insertion, perforation of the artery, blood clots, allergic reaction to the x-ray dye, and/or infection.
Additionally, it is possible that the procedure will not be successful, or that your artery will narrow again, requiring a repeat angioplasty or bypass surgery.
Potential benefits of PTA include: improved blood flow through the previously narrowed artery, reducing pain and/or restoring the function of the tissues downstream, decreased risk of ulcers, gangrene, amputation, and other complications in the areas affected by the arterial stenosis, avoidance of the risks and complications associated with a more invasive procedure, such as bypass surgery.
In a non-cardiac percutaneous transluminal angioplasty, or any procedure, you and your doctor must carefully weigh the risks and benefits to determine whether it's the right procedure for you.
After the Procedure
After your procedure, a pressure bandage will be applied to the catheter insertion site and you will be asked to lie still to prevent bleeding. You will be carefully monitored in the recovery area to be sure blood flow through the affected artery is maintained. Most patients are discharged the same day as their procedure, but some remain in the hospital 1-2 days for observation.
Once home, you should contact your doctor if you experience: redness, swelling, increasing pain, excessive bleeding, or discharge from the catheter insertion site, pain, tingling, numbness, or discoloration in the limb that was treated, cough, shortness of breath, or chest pain, inability to urinate, persistent nausea and vomiting, and/or signs of infection, such as fever and chills.
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