Interventional Therapy for PAD
In patients with claudication, the natural history of the limb disease is relatively benign in that the risk of progression to critical limb ischemia and limb loss is quite small. Therefore, the decision to proceed with interventional therapy in patients with claudication is typically based on lack of response to medical therapy and a suitable lesion for angioplasty or surgery.
Angioplasty with or without stenting has been evaluated in both the iliac and femoral arteries. Although the initial technical success is high (>90% for both), the durability of angioplasty with stenting is far greater in the iliac vessels.
The Trans-Atlantic Inter-Society Consensus (TASC) document provides summary recommendation for lesions that are appropriately treated with angioplasty. In the iliac arteries, a single stenosis of 10 cm or less, two stenoses less than 5 cm, and unilateral common iliac occlusion are best treated initially with angioplasty. In the femoral arteries, a single stenosis of 10 cm or less and multiple lesions each less than 3 cm may also be approached with angioplasty, typically without a stent.
Surgery for claudication generally involves two operations, the aortofemoral bypass and the femoral above-knee popliteal bypass. Aortofemoral bypass has good patency in older patients (80% patent at 10 years). However, these procedures have a 3% to 5% mortality risk and a 1% incidence of graft infection. Aortic surgery is a morbid operation from which an older patient frequently requires months to recover completely. Femoral popliteal bypass is less durable, with patencies of 50% to 60% at 5 years. Operative mortality rates up to 3% are typical when operating for claudication. In addition, femoral popliteal bypass is more likely to lead to limb threat following graft failure. The TASC recommendations for aortoiliac surgery are for more diffuse disease, which would include bilateral stenoses of 5-10 cm, diffuse, multiple unilateral stenoses greater than 10 cm, bilateral occlusions, and diffuse disease involving the aorta and iliac arteries. In the femoral vessels, similar criteria apply for surgery, including multiple stenoses or occlusions, each 3 to 5 cm, and complete common or superficial artery occlusions.