Peripheral vascular disease refers to diseases of blood vessels outside the heart and brain. It's often a narrowing of the vessels that carry blood to leg and arm muscles. There are two types of these circulation disorders:

• Functional peripheral vascular diseases don't have an organic cause and don't involve defects in blood vessels' structure. They're usually short-term effects and can come and go. Raynaud's disease (or Raynaud's phenomenon) is an example. It can be triggered by cold temperatures, emotional stress, working with vibrating machinery or smoking.
• Organic peripheral vascular diseases are caused by structural changes in the blood vessels (such inflammation and tissue damage). Peripheral artery disease is an example. It's caused by atherosclerosis.