NEWS & VIEWS DECADE IN REVIEW—PERIPHERAL VASCULAR DISEASE
10 Years of breakthroughs in peripheral vascular disease Mark A. Creager
Clinical trials published during the past decade have had substantial effects on the treatment of peripheral vascular diseases. In this article, I discuss ten important trials that have influenced treatment for common vascular disorders, including peripheral artery disease, abdominal aortic aneurysm, renal artery disease, extracranial carotid artery disease, and venous thromboembolism. Creager, M. A. Nat. Rev. Cardiol. 11, 635–636 (2014); published online 30 September 2014; doi:10.1038/nrcardio.2014.153
Patients with peripheral artery disease (PAD) are at increased risk of myocardial infarction, stroke, and cardiovascular death. Antiplatelet therapy, including aspirin, is recommended for patients with PAD. Two prospective studies were designed to deter mine whether aspirin can prevent cardio vascular events in asymptomatic patients with PAD. Investigators in the Aspirin for Asymptomatic Atherosclerosis Trial1 recruited 28,980 individuals free from clinical cardiovascular disease, of whom 3,350 were found to have PAD on the basis of an ankle–brachial index (ABI) ≤0.95. Participants received either aspirin (100 mg daily) or placebo, and were followed up for a mean of 8.2 years. The primary end point of fatal or nonfatal coronary events, stroke, or revascularization was not significantly different between the aspirin and placebo groups (HR 1.03, 95% CI 0.84–1.27).1 In the POPADAD trial,2 investigators exam ined the efficacy of aspirin in reducing cardiovascular events in 1,276 patients with asymptomatic PAD (defined as an ABI ≤0.99) and either type 1 or type 2 diabetes mellitus. Patients received aspirin (100 mg daily) or placebo, and were followed up for a median of 6.7 years. No significant differ ence in the primary composite end point of fatal coronary heart disease or stroke, nonfatal myocardial infarction, nonfatal stroke, or above ankle amputation for criti cal limb ischaemia was observed in patients treated with or without aspirin (HR 0.98, 95% CI 0.76–1.26).2 These findings reject the notion that aspirin therapy is effective for all
patients with PAD, and led to modifications in ACCF/AHA guideline recommendations regarding the use of antiplatelet therapy in patients with asymptomatic PAD.
‘‘
These findings reject the notion that aspirin is effective for all patients with PAD...
’’
Although both exercise training and endovascular revascularization improve symptoms of intermittent claudication in patients with PAD, the merits of each treat ment have been controversial. The CLEVER study 3 involved 111 patients with PAD and aortoiliac artery stenosis randomly allo cated to receive optimal medical therapy alone, or in combination with supervised exercise training or stent revascularization. After 6 months, the change in peak walking time was greater in the exercise group than in the stenting group (5.8 ± 4.6 min versus 3.7 ± 4.9 min; P = 0.04), and both interven tions were superior to medical therapy alone (1.2 ± 1.6 min; P
10 Years of breakthroughs in peripheral vascular disease Mark A. Creager
Clinical trials published during the past decade have had substantial effects on the treatment of peripheral vascular diseases. In this article, I discuss ten important trials that have influenced treatment for common vascular disorders, including peripheral artery disease, abdominal aortic aneurysm, renal artery disease, extracranial carotid artery disease, and venous thromboembolism. Creager, M. A. Nat. Rev. Cardiol. 11, 635–636 (2014); published online 30 September 2014; doi:10.1038/nrcardio.2014.153
Patients with peripheral artery disease (PAD) are at increased risk of myocardial infarction, stroke, and cardiovascular death. Antiplatelet therapy, including aspirin, is recommended for patients with PAD. Two prospective studies were designed to deter mine whether aspirin can prevent cardio vascular events in asymptomatic patients with PAD. Investigators in the Aspirin for Asymptomatic Atherosclerosis Trial1 recruited 28,980 individuals free from clinical cardiovascular disease, of whom 3,350 were found to have PAD on the basis of an ankle–brachial index (ABI) ≤0.95. Participants received either aspirin (100 mg daily) or placebo, and were followed up for a mean of 8.2 years. The primary end point of fatal or nonfatal coronary events, stroke, or revascularization was not significantly different between the aspirin and placebo groups (HR 1.03, 95% CI 0.84–1.27).1 In the POPADAD trial,2 investigators exam ined the efficacy of aspirin in reducing cardiovascular events in 1,276 patients with asymptomatic PAD (defined as an ABI ≤0.99) and either type 1 or type 2 diabetes mellitus. Patients received aspirin (100 mg daily) or placebo, and were followed up for a median of 6.7 years. No significant differ ence in the primary composite end point of fatal coronary heart disease or stroke, nonfatal myocardial infarction, nonfatal stroke, or above ankle amputation for criti cal limb ischaemia was observed in patients treated with or without aspirin (HR 0.98, 95% CI 0.76–1.26).2 These findings reject the notion that aspirin therapy is effective for all
patients with PAD, and led to modifications in ACCF/AHA guideline recommendations regarding the use of antiplatelet therapy in patients with asymptomatic PAD.
‘‘
These findings reject the notion that aspirin is effective for all patients with PAD...
’’
Although both exercise training and endovascular revascularization improve symptoms of intermittent claudication in patients with PAD, the merits of each treat ment have been controversial. The CLEVER study 3 involved 111 patients with PAD and aortoiliac artery stenosis randomly allo cated to receive optimal medical therapy alone, or in combination with supervised exercise training or stent revascularization. After 6 months, the change in peak walking time was greater in the exercise group than in the stenting group (5.8 ± 4.6 min versus 3.7 ± 4.9 min; P = 0.04), and both interven tions were superior to medical therapy alone (1.2 ± 1.6 min; P
