ROME — New international guidelines on the management of peripheral arterial disease recommend an expanded role for endovascular therapies at the expense of open surgical procedures, Dr. Lars Norgren reported at the annual meeting of the Cardiovascular and Interventional Radiological Society of Europe.
The first report of the TransAtlantic Inter-Society Consensus (TASC-I) on the management of peripheral arterial disease, published in 2000, recommended endovascular therapies as the procedures of choice in patients with morphologically focal type A lesions of the iliac or femoropopliteal arteries, and surgery for their opposite—type D lesions—which are diffuse, extensive, and multilevel.
These recommendations remain unchanged in TASC-II, to be published late this year, although the length of stenosis that qualifies lesions as type A has been expanded. The big change in TASC-II involves the morphologically intermediate type B and type C lesions. TASC-I concluded that more evidence was needed before firm treatment recommendations for B and C lesions could be made, whereas TASC-II comes down in favor of endovascular therapy for type B and surgery for type C lesions, said Dr. Norgren, professor of surgery at Lund (Sweden) University.
“The patient's comorbidities, the informed patient's preferences, and local operators' success rates must be considered when making treatment recommendations for type B and C lesions,” he added.
Dr. Norgren noted that this is a rapidly changing field, and the best form of interventional therapy for specific lesion types remains in flux pending the outcome of randomized trials. A feature of the TASC-II report that might be more important than the lesion-type treatment recommendations is TASC-II's conscious effort to address the new guidelines to primary care providers and other referring physicians, he said.
TASC-I was influential in the daily practice of vascular specialists, who tended to view the guidelines as an unbiased multidisciplinary expert consensus on how best to manage peripheral arterial disease (PAD). But TASC-I had little effect on patient referral patterns; indeed, the unwieldy 250-plus page report (J. Vasc. Surg. 2000;31:S1–296; Eur. J. Vasc. Endovasc. Surg. 2000; 19[Suppl. A]:S1–244; also available at www.tasc-pad.org
To overcome this shortcoming, TASC-II will be an abbreviated, more reader-friendly document. After its publication, members of the TASC-II working group will speak at meetings of the major primary care medical societies.
“We know that TASC-I had too much text, too much technical detail,” Dr. Norgren said. “We've started again with the intention to keep more of the wording out.”
In keeping with the new primary care focus, TASC-II emphasizes the high cardiovascular event rate in patients with intermittent claudication (IC), and the primacy of medical management in IC patients, including smoking cessation, diabetes control, hypertension management, and lipid-lowering therapy. The guidelines stress that all patients with symptomatic PAD should be on long-term antiplatelet therapy, with the best-quality evidence supporting aspirin.
A supervised exercise program should always be considered as part of the initial therapy of IC. “There is very little evidence that unsupervised exercise works,” Dr. Norgren said.
TASC-II recommends a 3- to 6-month trial of pharmacotherapy with a vasoactive agent—cilostazol (Pletal) is the only one approved in the United States, and naftidrofuryl the sole European drug—as part of the initial therapy for IC. This is a stronger endorsement of pharmacotherapy than that made in TASC-I. In the interim, clinical trials have provided more persuasive evidence of efficacy by excluding patients with critical limb ischemia who, it's now clear, are unlikely to benefit from the drugs.
Dr. Norgren's TASC-II presentation received a mixed reception. Some interventional radiologists declared that they already consider endovascular techniques the best procedures for many type C lesions and anticipate the day when type D femoropopliteal lesions will come within their purview as well.
But Dr. Cathal Kelly, a vascular surgeon at Beaumont Hospital, Dublin, said he is concerned that the guidelines rely on data reported from top-flight endovascular centers that achieve better results than those found in routine practice elsewhere.
He added that many endovascular therapists have perhaps too low a threshold for intervening in IC, given that it's largely a benign condition, with only about 5% of conservatively managed patients developing critical limb ischemia during a 5-year period. Dr. Kelly said “surgeons all over the world” are concerned that failed endovascular therapy for more complex lesions compromises the ability to perform successful bypass surgery and increases the risk of amputation.
This is a rapidly changing field, and the best form of interventional therapy remains in flux pending the outcome of trials. DR. NORGREN
Angiograms of a 68-year-old man show a 20-cm occlusion of the right superficial femoral artery (arrows, left) and the results of percutaneous revascularization with a stent (right). ©Elsevier, Curr Probl Cardiol, Nov 2006; 31: 711–760
