Laser angioplasty of peripheral arteries: basic principles, current clinical studies, and future directions.

Percutaneous transluminal angioplasty (PTA) is a routine procedure for the treatment of peripheral arterial disease. However, its main limitation is late restenosis occurring at a 1-year rate of 6%-60%. Restenosis arises from injury to the arterial wall including overstretching, compression and rupture of the atherosclerotic plaque during balloon inflation. It is hypothesized that better long-term angioplasty results are observed if atherosclerotic plaques are removed rather than compressed and fractured. Laser angioplasty is one method to remove atherosclerotic plaques. We discuss the principles of lasers, physical properties of laser light, history of laser angioplasty and effects of laser radiation on tissues. Large clinical studies using laser angioplasty are critically assessed. In comparison to conventional PTA, there are some advantages of laser angioplasty: easier passage through chronic and calcified occlusions and according to some studies, better short- and medium-term results regarding limb salvage and management of in-stent restenoses. The main drawback of laser angioplasty is that current laser catheters are not able to create a sufficiently wide channel in the occlusion, meaning that adjunctive balloon dilatation is still required. Thus, long-term data may be misleading. Basic and applied research should continue to focus on enlargement of plaque ablation.