What Is Peripheral Vascular Disease (PVD) or Peripheral Artery Disease (PAD)?

Peripheral vascular disease (PVD) or peripheral arterial disease (PAD) is a slow and progressive circulation disorder. It may involve disease in any of the blood vessels outside of the heart and diseases of the lymph vessels - the arteries, veins, or lymphatic vessels. Organs supplied by these vessels such as the brain, heart, and legs, may not receive adequate blood flow for ordinary function. However, the legs and feet are most commonly affected, thus the name peripheral vascular disease.

Conditions associated with PVD that affect the veins include deep vein thrombosis (DVT), varicose veins, and chronic venous insufficiency. Lymphedema is an example of PVD that affects the lymphatic vessels.

When PVD occurs in the arteries outside the heart, it may be referred to as peripheral arterial disease (PAD). PAD is generally associated with blocked arteries of the legs. The blockage most often is the result of a chronic buildup of hard fatty material (atherosclerosis or hardening of the arteries) into the inside lining of the arterial wall of the legs.

This ultimately narrows and blocks the flow of blood which carries oxygen and nutrients to the limb. The femoral and popliteal arteries are the major arterial blood supply to the lower extremities and are a common location for atherosclerotic disease to develop.

The presence of atherosclerosis in the leg arteries is a strong indicator that there is also atherosclerosis in the arteries of the heart and brain, because atherosclerosis is a widespread disease of the arteries.

Atherosclerosis of the leg arteries may cause a blockage, obstructing blood flow, and potentially result in pain in the leg(s), ulcers or wounds that do not heal, and/or the need for amputation (surgical removal) of a foot or leg. 

Therefore, PAD has two major complications associated with its presence: limb complications (nonhealing wounds, ulcers, gangrene, loss of a limb) and risk for stroke and/or heart attack.

However, the terms "peripheral vascular disease" and "peripheral arterial disease" are often used interchangeably. In the US, 10 million people have peripheral artery disease. PAD occurs in 5 percent of adults older than 50 and in 20 percent of adults older than 70. It is frequently found in people with coronary artery disease, because atherosclerosis, which causes coronary artery disease, is a widespread disease of the arteries.

Conditions associated with PAD may be occlusive (occurs because the artery becomes blocked in some manner) or functional (the artery either constricts due to a spasm or expands). Examples of occlusive PAD include peripheral arterial occlusion and Buerger's disease (thromboangiitis obliterans). Examples of functional PAD include Raynaud's disease and phenomenon and acrocyanosis.