New practice guidelines for managing PAD
W. Kent Williamson, M.D.
Medical director, Providence Noninvasive Vascular Labs
Chairman, Providence Vascular Quality Council-Oregon
Pacific Vascular Specialists
David A. Ellis, M.S.
Clinical vascular research associate
Providence St. Vincent Medical Center
Published February 2012
The American Heart Association and the American College of Cardiology recently published new guidelines for evaluating and managing peripheral arterial disease. Published in September 2011, the updated recommendations include:
Ankle-brachial index evaluation.
The authors now recommend that primary care providers evaluate at-risk patients beginning at age 65 instead of the previous threshold of age 75. The guideline is based primarily on the German epidemiologic trial
on ankle-brachial index. In this study, 21 percent of patients over age 65 had either symptomatic or asymptomatic PAD.
The ABI test should be used primarily in at-risk or selected patients. The authors note that further screening studies are needed before recommendation of widespread ABI screening. The expected benefit of targeted diagnostic testing is to allow early identification of PAD and earlier preventive steps, such as antiplatelet therapy.
Antiplatelet therapy. New recommendations state that the appropriate dose of aspirin ranges from 75 to 325 mg daily, and that clopidogrel should be considered in those who cannot tolerate aspirin.
Combination therapy with aspirin and clopidogrel may be considered in select high-risk patients, such as those with previous MI. This is based on evidence that combination therapy may reduce the incidence of a second MI by a small degree. Further, warfarin is not recommended solely for treating PAD, given that it provides no clear benefit and carries a higher risk of bleeding.
Smoking cessation. The new recommendations stress a greater need to help patients stop smoking. The authors suggest that providers:
- Ask patients who are smokers or former smokers about the status of their tobacco use at every visit.
- Help patients to find counseling and to develop a plan for quitting that may include pharmacotherapy or referral to a smoking-cessation program.
- In the absence of contraindication or other compelling clinical indication, offer one or more of the following pharmacological therapies: varenicline, bupropion or nicotine replacement.
Critical limb ischemia. Features of CLI include tissue loss and rest pain, and treatments include either surgical or endovascular revascularization. Based on the results of a large study, the consensus group now recommends surgery as a first-line treatment for patients who have a life expectancy of two years or longer.
Autologous bypass for CLI is associated with statistically significant longer life expectancy and an improved limb-salvage rate compared with endovascular therapy as the first-line treatment.
One theory behind the lower survival and limb-salvage rates for those treated with endovascular therapy is that this group requires more procedures and hospitalizations. For those patients with life expectancy of less than two years, however, the outcomes for surgical vs. endovascular therapy are similar, so endovascular therapy is a reasonable first-line treatment.
Abdominal aortic aneurysm. The new recommendations for managing AAA state that either open or endovascular repair is a reasonable option, but that endovascular repair must be followed up with regular surveillance to detect AAA growth or graft migration.
The authors note that endovascular repair of AAA is associated with lower perioperative complications, but that after the perioperative period, outcomes are similar between those who have had open repair and those who have had endovascular repair. For those patients who fail to receive regular follow-up after endovascular repair, AAA-related mortality is higher than in the open group, which highlights the need for close follow-up.
The American Heart Association’s new guidelines represent significant changes from the 2005 guidelines, and are a valuable effort to incorporate data-driven best evidence into clinical practices. These guidelines serve as critical reference for the management of all vascular patients.
Clinical articles by W. Kent Williamson, M.D.