Occlusive Disease
The ideal hemodialysis vascular access is one that provides reliable, complication-free access to deliver prescribed dialysis
Peripheral arterial occlusive disease is the 2nd most common non-traumatic cause of amputations worldwide.
On the inside, normal arteries are smooth and unblocked. As time passes, atheromatous plaques accumulate in their wall, causing their interior lining to thicken and become slender. Cholesterol, calcium, destroyed cells, and fibrous tissue make up the plaques. Similar to the furring of water pipes, this process is known as atherosclerosis, or the hardening of the arteries.
A plaque may be complicated by bleeding in it, cracking of its surface and blood clotting. Complicated atherosclerosis may cause narrowing (stenosis) or complete blockage (occlusion) of an artery, and usually occurs close to the areas where arteries divide into branches.
Blood rich in nutrients and oxygen is transported from the heart to the rest of the body through arteries. When the arteries in the legs develop enough plaque to reduce the blood flow in them, because of stenosis or occlusion, the condition is called peripheral arterial occlusive disease (PAOD). The arteries which may be affected by PAOD are the abdominal aorta, the iliac, the femoral, the popliteal and the tibial arteries.
Do I need to treat this if
I have no symptoms?
- You may have no symptoms and still have atherosclerosis causing occlusive disease in your leg arteries or in the arteries supplying vital organs, like the heart or the brain.
- It is important to start treatment for this disease in the early stages, because it may increase the risk of losing a leg, but also of suffering a heart attack or a stroke.
What causes PAOD?
- It is caused by atherosclerosis of the peripheral arteries (aorta and leg arteries).
- It affects individuals of advanced age (usually over 60 years). One in three people over 70 years have PAOD. Men have a greater risk than women.
- It is much more common in smokers, diabetics, people with high cholesterol, people with high blood pressure and people with obesity. The conditions predisposing to atherosclerosis are called (atherosclerotic) risk factors. Coincidence of two or more risk factors increases the risk of POAD significantly.
Initially, your physician will ask about your general health state, your symptoms and your medical history (other medical conditions and risk factors you may have). Then, he/she will examine you, especially in the abdomen and the legs (groins, behind the knees, feet) to assess the strength of your pulses in your arteries.
If your physician suspects PAOD, it is possible to proceed to simple tests such as:
- Ankle-brachial pressure index (ABPI or ABI) measurement, by measuring and comparing the systolic blood pressure in your arms and legs
- Blood tests, including cholesterol and other markers for peripheral artery disease
For more precise assessment of the extent of the disease and the severity of the blockages in your arteries – particularly if operative management is planned the surgeon may order: Colour-flow duplex ultrasonography, CT/MR peripheral angiogram. This painless test uses ultrasounds and can show your physician how open your arteries are and how quickly blood flows through them.
Digital subtractive angiography (DSA) of the abdominal aorta, iliac and lower limb arteries. This is an invasive test using x-rays to take pictures of the arteries by injecting contrast in them. Under local anaestesia in your groin or arm, an artery is punctured and then a catheter is advanced to the area of interest
Computed tomographic angiography (CTA). It uses x-rays for imaging of the blockages of the arteries
Magnetic resonance angiography (MRA). It uses magnetic fields and radio waves for imaging of the blockages of the arteries.
Smaller branches of the arteries(the “collateral circulation”) can grow and carry more blood to the limb and the muscles of the limb as a coping mechanism to the reduced blood circulation in the leg.
How is Peripheral arterial disease treated?
There are three lines of treatment: Conservative management, open operation and endovascular procedure (balloon angioplasty and/or stenting).
- Changes of lifestyle (See below What can I do to help myself?)
- All patients need to take an antiplatelet drug (Aspirin or similar) and lipid-lowering drugs (statins, fibrates)
- Walking exercise. Regular walking, for example at least 30 minutes 3-5 times a week, may help improve your symptoms within a few month
Arterial bypass operation with a graft
With this operation a new artery for blood flow to your leg is created bypassing the blockage of your artery. As bypass graft, the vascular surgeon uses a vein from your leg or a plastic tube, and connects it above and below the blockage. This procedure may be performed under general or spinal anaesthesia.
Balloon Angioplasty and/or stent placement
In certain cases like short blockages in large arteries, your vascular surgeon will select this procedure to increase the blood flow to your leg. This is commonly performed under local anaesthesia. The blockage is opened with a balloon under x-ray guidance. Occasionally, a metal stent is inserted to fit the dilated artery and hold it open. The value of this procedure is controversial in cases of intermittent claudication. The decision about the type of management depends upon the morphology and the extent of blockages as well as the general state of your health.
Quitting smoking completely
Exercising aerobically, such as brisk walking,
for 25 to 30 minutes dailyTaking your medication to control blood
pressure, blood cholesterol and diabetes
