Aortoiliac Occlusive Disease

What is aortoiliac occlusive disease?
Aortoiliac occlusive disease occurs when your iliac arteries become narrowed or blocked. The main artery in the body, the aorta, splits into two branches supplying each leg.  These branches are called the iliac arteries. The iliac arteries go to your legs, where they divide into many smaller arteries that run down to your toes. Aortoiliac disease is a narrowing of the aorta and/or iliac arteries causing disturbances in blood flow.

As people age, plaque can build up in the walls of arteries. Plaque is composed of cholesterol, calcium, and fibrous tissue. The more plaque builds up, the more arteries narrow and stiffen. This process is called atherosclerosis, or hardening of the arteries. Eventually, enough plaque builds up to interfere with blood flow in your iliac arteries or leg arteries.
As the iliac arteries become narrowed or blocked, your legs may not receive the blood and oxygen they need. This lack of oxygen is called ischemia and it can cause pain. In severe cases, ulcers or gangrene can develop, which can even result in losing a limb. However, these developments are uncommon unless the process is not treated and is allowed to progress.

What are the symptoms?
Early on patients may feel pain, cramping, or fatigue in the legs when walking or exercising. The pain with walking usually occurs in your buttocks, thighs, and legs. This is called intermittent claudication because it stops with rest. As the disease progresses, the pain occurs after shorter distances. Ultimately, patients may develop pain at rest.  Some men who have aortoiliac occlusive disease also lose the ability to have or maintain an erection.

Signs of advanced disease include:

• Severe pain, coldness, and numbness in a limb
• Sores on your toes, heels, or lower legs
• Weakened muscles in your legs
• Gangrene (tissue death), which may require amputation

If you experience any of these advanced symptoms, it usually means that your leg arteries are blocked in more than one place. Your physician may need to treat more than one site to prevent gangrene or limb loss.
What causes aortoiliac occlusive disease?

• Most cases are caused by atherosclerosis.
• Risk factors for hardening of the arteries include:
• Smoking
• High cholesterol
• High blood pressure
• Obesity
• Having a family history of heart disease

In rare cases, other conditions can cause blockages of the arteries.

What tests will I need?
After inquiring about your medical history and conducting a physical exam, if your physician suspects you may have aortoiliac disease, he or she may perform tests to further define its extent and severity, such as:

Ankle-brachial index (ABI)
For the non-invasive ABI, blood pressure is measured in your ankle and in your arm. These two numbers are compared to determine your ABI. Normally, the blood pressures in your ankle and arm should be about equal. If your ABI is low, you may have aortoiliac disease.

Doppler ultrasound
Doppler ultrasound is another test that uses sound waves to show blood flow and problems with the structure of blood vessels. This test better identifies specific arteries that are blocked.

Angiography
There are three types of arteriography that may be performed: contrast arteriography, CT angiography (CTA), and MR Angiography (MRA).
Contrast arteriography usually provides better resolution but is a more invasive test.  Contrast dye is injected into the arteries and then x-ray images are taken which reveal the structure of the arteries. This test finds the exact location and pattern of blockages.  One of the benefits of this test is that if a blockage is identified and is appropriate for treatment by angioplasty and a stent, this procedure may be carried out at the same time.
CTA and MRA are scans that are specifically dedicated to evaluating your blood vessels and identifying if blockages are present.

How is aortoiliac occlusive disease treated?

Lifestyle Changes
If you are a smoker, the most important step you can take is to quit smoking. Chemicals in tobacco can damage your arteries and also increase your chance of having complications from aortoiliac occlusive disease.
Maintaining a healthy weight, following a structured walking program at least 3 or 4 times a week, and eating a low-fat and high-fiber diet can help slow hardening of the arteries. Medications to lower the cholesterol may also be prescribed.
Strict blood pressure and diabetes control are also important.
Diabetics may also develop impaired sensation of the feet, a condition called neuropathyIn such cases, it is important to practice good foot hygiene, wear protective, well fitting, and cushioned footwear, and avoid injuries to your foot. This type of care can be very important because, as you lose the protective feeling in your feet, you can develop sores on them that may be difficult to heal.

Angioplasty or Surgery
For severe aortoiliac occlusive disease, particularly if it does not improve with the measures described above, your physician may recommend a minimally invasive treatment called angioplasty to improve the circulation in your legs. For more extensive blockages or those that cannot be treated with angioplasty, surgery to bypass or clear your blocked arteries may be required.
During an angioplasty procedure, a balloon is directed to the affected artery and pushes the plaque in your artery against your artery walls, widening the vessel. In some circumstances, a tiny mesh-metal tube called a stent may then be placed into the narrowed area of your artery to keep it open. The stent remains permanently in your artery. After successful angioplasty, blood flows more freely through your artery.

Bypass surgery creates a detour around the narrowed or blocked sections of your artery. Although more invasive, bypass surgery restores blood flow in about 85 percent of patients. Results are commonly maintained for 10 or more years.

Another treatment is an endarterectomy.  Here, your vascular surgeron removes the plaque contained in the inner lining of the diseased artery. This leaves a wide-open artery and restores blood flow through your leg artery.
The best choice of the treatment depends upon the pattern of blockage as well as how much blockage you have. Your vascular surgeon will help you determine which method of treatment is best for your particular situation.