Fulfilling the Promise of Percutaneous Angioplasty

It is ironic that in 1964, Dotters’ initial application of percutaneous transluminal angioplasty (PTA) targeted femoral-popliteal stenoses.1 Now, nearly 4 decades later, although angioplasty has gained wide acceptance as a first-line treatment for diseased coronary, iliac, and renal arteries, its role in femoral-popliteal vessels remains controversial and poorly defined. The initial PTA procedure is nearly always a success. Improved technology, including slick guidewires, sleek balloons, and sinuous stents can reliably open most femoral-popliteal obstructions. However, one cannot attempt angioplasty in the lower legs without running into its Achilles heel: restenosis. In contradistinction to angioplasty in the coronary, iliac, and renal vasculature, restenosis rates after lower-extremity PTA are unacceptably high. The femoral-popliteal system has unique anatomic and physiological properties. Blood flow rates are low, resistance is high, and lesions are often very long, with poor run-off. These characteristics raise the risk of recurrence to well over 50%, and in some reports, over 80%.2 3 Alternative surgical approaches using saphenous and prosthetic grafts provide better long-term patency but cause significantly more morbidity.4 Often, patients with peripheral vascular disease also have cardiac, cerebrovascular, and/or renal disease that increases the risk of major surgery. Although surgery is often embraced for limb salvage, surgery for the treatment of claudication is generally avoided. It is not surprising, therefore, that so many vascular medicine specialists currently recommend conservative medical therapy and walking programs as a first-line treatment for symptomatic femoral-popliteal disease.Over the past decade, much has been learned about the mechanism of restenosis. There are 2 major components of restenosis: the first is the mechanical renarrowing of the dilated region; the second is the biological proliferative response to injury.5 6 Percutaneous angioplasty is a purely mechanical intervention. In recent years, our mechanical tools have improved considerably. Careful quantitative angiography has taught us …