Peripheral artery disease (PAD) is a progressive disease occurring as a result of plaque accumulation (atherosclerosis) in the arterial system that carries blood to the extremities (arms and legs) as well as vital organs. The vessels that are most affected by PAD are the arteries of the lower extremities, the aorta, the visceral arterial branches, the carotid arteries and the arteries of the upper limbs. In the lower extremities, PAD affects three major arterial segments i) aortic-iliac, ii) femoro-popliteal (FP) and iii) infra-popliteal (primarily tibial) arteries. The disease is commonly classified clinically as asymptomatic claudication, rest pain and critical ischemia.
A stent is a wire mesh “scaffold” that is permanently implanted in the artery to keep the artery open and can be combined with angioplasty to treat PAD. There are two types of stents: i) balloon-expandable and ii) self expandable stents and are available in varying length. The former uses an angioplasty balloon to expand and set the stent within the arterial segment. Recently, drug-eluting stents have been developed and these types of stents release small amounts of medication intended to reduce neointimal hyperplasia, which can cause re-stenosis at the stent site. Endovascular stenting avoids the problem of early elastic recoil, residual stenosis and flow limiting dissection after balloon angioplasty.