What is Peripheral Vascular Disease (PVD)?

Arteriosclerosis/Atherosclerosis

This is a process which causes narrowing and hardening of the arteries. It is characterized by the following process:

• Fatty streak (early lesion)
• Atheromatous plaques (mature lesion) which may gradually enlarge and thicken, and undergo calcification, haemorrhage, or rupture due to weakness in the plaque.
• Formation of thrombus (clot) at the site of the ruptured plaque. If this happens, and the thrombus enlarges, the blood flow may be completely blocked.

Calcium deposits in the artery walls also contribute to the progressive “stiffening” or “hardening” of the arteries, which compounds the build up of atheroma to cause a poorer blood flow.

Atheroma can build up silently over many years; and gradual narrowing may cause less severe symptoms than a sudden blockage, as an alternative collateral circulation has time to form.

The term “collateral circulation” in this context refers to the opening up of smaller arteries, as an alternative route to carry blood around the blockage to the tissues beyond.

Arteriosclerosis can affect any artery in the body, such as:

• The aorta and iliac arteries, leading most commonly to aortic aneurysm or, (if the lower aorta and/ or both common iliac arteries are affected) ischaemia of the buttocks and thighs.
• The coronary arteries supplying the heart. If the narrowing is enough to cause symptoms, this is known as ischaemic heart disease (IHD) and leads to angina and heart attacks. Click here for IHD guidance
• The arteries supplying the brain. This is known as cerebrovascular disease, and may lead to transient ischaemic attacks or strokes. Click here for Stroke guidance
• The arteries supplying limbs This is known as peripheral vascular disease (PVD) and usually affects the femoral and popliteal arteries (lower limbs)
• Much more rarely, the arteries in the upper limbs are affected. However, arteriosclerosis is very uncommon in arteries supplying the upper limb.

It would be assumed that if a person has arteriosclerosis affecting the lower limbs, arteriosclerosis will also be present in many other parts of the body, and that a person with advanced peripheral vascular disease may be in a poor clinical condition generally.

The effects vary and depend on the severity of the narrowing and hardening of the arteries, at what level it occurs and whether an adequate collateral circulation has been built up.

PVD affects the legs eight times more commonly than the arms and in this context is also known as Lower Limb Ischaemia.

In this guidance the emphasis is on PVD affecting the lower limbs.

Click on the links for details of:

• Major Risk Factors for PVD
• The Mechanism of Claudication
• Effects of Arteriosclerosis / Arterial Disease Diagram

Amended April 2008