Your arteries carry blood rich in oxygen and nutrients from your heart to the rest of your body. When the arteries in your legs become blocked, your legs do not receive enough blood or oxygen, and you may have a condition called peripheral artery disease (PAD), sometimes called leg artery disease.
PAD can cause discomfort or pain when you walk. The pain can occur in your hips, buttocks, thighs, knees, shins or upper feet. Leg artery disease is considered a type of peripheral artery disease because it affects the arteries, blood vessels that carry blood away from your heart to your limbs. You are more likely to develop PAD as you age. One in 3 people age 70 or older has PAD. Smoking or having diabetes increases your chance of developing the disease sooner.
The aorta is the largest artery in your body and it carries blood pumped out of your heart to the rest of your body. Just beneath your belly button in your abdomen, the aorta splits into the two iliac arteries, which carry blood to each leg. When the iliac arteries reach your groin, they split again to become the femoral arteries. Many smaller arteries branch from your femoral arteries to take blood down to your toes.
Your arteries are normally smooth and unobstructed on the inside but, as you age, they can become blocked through a process called atherosclerosis, which means hardening of the arteries. As you age, a sticky substance called plaque can build up in the walls of your arteries. Plaque is made up of cholesterol, calcium and fibrous tissue. As more plaque builds up, your arteries narrow and stiffen. Eventually, enough plaque builds up to reduce blood flow to your leg arteries. When this happens, your leg does not receive the oxygen it needs. Physicians call this leg artery disease. You may feel well and still have leg artery disease or sometimes similar blockages in other arteries, such as those leading to the heart or brain. It is important to treat this disease not only because it may place you at a greater risk for limb loss, but also for having a heart attack or stroke.
What are the symptoms?
You may not feel any symptoms from peripheral artery disease at first. The most common early symptoms is intermittent claudication (IC). IC is discomfort or pain in your legs that happens when you walk and goes away when you rest. You may not always feel pain; instead you may feel a tightness, heaviness, cramping or weakness in your leg with activity. IC often occurs more quickly if you walk uphill or up a flight of stairs. Over time, you may begin to feel IC at shorter walking distances. Only about 50% of the people with leg artery disease have blockages severe enough to experience IC.
Critical limb ischemia is a symptom that you may experience if you have advance peripheral artery disease. This occurs when your legs do not get enough oxygen even when you are resting. With critical limb ischemia, you may experience pain in your feet or in your toes even when you are not walking.
In severe peripherl artery disease, you may develop painful sores on your toes or feet. If the circulation in your leg does not improve, these ulcers can start as dry, gray or black sores and eventually become dead tissue (called gangrene).
What causes peripheral artery disease (PAD)?
Athlerosclerosis causes peripheral artery disease. As you get older, your risk of developing leg artery disease increases. People older than age 50 have an increased risk of developing the disease, and men have a greater risk than women.
Other factors that increase your chances of developing the disease include:
- High blood pressure
- High cholesterol or triglycerides
- High levels of homocysteine, an amino acin in your blood
- Weighing over 30% more than your ideal weight
What tests will I need?
First your physician asks you questions about your general health, medical history and symptoms. In addition, your physician conducts a physical exam. Together these are known as a patient history and exam. As part of your history and exam, your physician will ask you if you smoke or have high blood pressure. Your physician will also want to know when your symptoms occur and how often. As part of the physical exam, your physician will conduct pulse tests, which measure the strength of your pulse in arteries behind your knees and feet.
After your exam, if your physician suspects peripheral artery disease, he or she may perform tests, such as:
- Ankle-brachial index (ABI), which compares the blood pressure in your arms and legs
- Blood tests for cholesterol or other markers for artery disease
- To better understand the extent of your leg artery disease, your physician may also recommend duplex ultrasound, pulse volume recording or angiogram
- Duplex ultrasound uses high-frequency sound waves to measure real-time blood flow and detects blockages or other abnormalities in the structure of your blood vessels
- Pulse volume recording measures the volume of blood at various points in the legs usng an arm blood pressure cuff and a Doppler probe
- Angiogram, which produces X-ray pictures of the blood vessels in your legs using a contrast dye to highlight your arteries
- Physicians usually reserve angiogram for people with more severe forms of leg artery disease
An atherectomy is a procedure in which your vascular surgeon inserts a specialized catheter into a blocked artery to remove a buidup of atheroclerotic plaque from within the vessel. The catheter contains a sharp rotating blade, grinding bit or laser filament as well as a collection system that permits your surgeon to remove the plaque from the wall of the vessel and collect or suction any resulting debris.
Atherectomy is typically used to treat blockages where angioplasty and stenting cannot be performed. This may be as a result of anatomical factors, the location of the blockage, the hardness of the plaque or other factors. More commonly, atherectomy is uses as a complement to angioplasty and stenting, removing significantly hardened blockages and allowing for the insertion of a balloon and stent. A stent is a small metal device that helps to prevent a blockage from reforming at the same location.
A variety of catheters can be used for this procedure, with the type of catheter being used dependent on the nature of the blockage treated.
For more information on the diagnosis, treatment and procedures regarding vascular disease, visit www.vascularweb.org.