Practice Update: Cardiology

AMERICAN HEART ASSOCIATION ANNUAL SCIENTIFIC SESSIONS 28

Ticagrelor nomore effective than clopidogrel in patients with prior lower extremity revascularisation for peripheral artery disease In the Examining Use of

S chuyler Jones, MD, of the Duke University School of Medicine, Durham, North Carolina, explained that peripheral artery disease is considered a systemic manifestation of atherosclerosis. It affects the arteries of the lower extremities, and is often thought to constitute a coronary heart disease risk equivalent due to associated high cardiovascular morbidity and mortality. He said, “Considering the uncertainty about long-term risk reduction after vascular intervention and dramatic variation in antiplatelet use after vascular intervention, we were interested in ascertaining patient risk after pulmonary vein isolation and whether we could demonstrate (in the largest subgroup of EUCLID patients) ticagrelor’s effectiveness in reducing cardiovascular risk. Symptomatic patients most commonly present with either intermittent claudication or critical limb ischaemia. These symptoms are often the focus of treatment strategies to revascularise the limb. Unlike patients with coronary artery disease, how to reduce cardiovascular risk in patients with symptomatic peripheral artery disease (whether treated with revascularisation or medical therapy) is not well understood. Clinicians often rely on data from subgroup analyses of patients with peripheral artery disease in antiplatelet and statin studies to guide cardiovascular risk reduction strategies.

With limited proven medical therapies to reduce symptoms in patients with peripheral artery disease, peripheral endovascular and surgical revascularisation for the symptomatic management of patients with peripheral artery disease has increased dramatically over the past two decades. Compared with revascularisation for coronary artery disease, little evidence guides clinicians on the choice and use of antiplatelet medications in patients who have undergone a peripheral revascularisation procedure. The optimal antithrombotic regimen for long-term management of patients with peripheral artery disease after revascularisation is poorly defined and often extrapolated from trials of patients undergoing a percutaneous coronary intervention. Two critical questions surround long-term prognosis and management of patients who have undergone prior lower extremity revascularisation: 1. Are patients who have been revascularised at heightened risk for cardiovascular and limb events vs those who have not undergone prior revascularisation? 2. Are more intensive antiplatelet medications more effective yet safe in this population? Ticagrelor is a potent P2Y12 receptor antagonist with evidence of benefit in patients with acute coronary syndromes and those with prior myocardial infarction. The EUCLID trial was designed to evaluate treatment, specifically in patients with peripheral artery disease. EUCLID tested the hypothesis that monotherapy with ticagrelor would be superior to clopidogrel in preventing cardiovascular endpoints in patients with peripheral artery disease. Dr Jones described findings in the subgroup of patients who were enrolled based on their history of a prior lower extremity revascularisation. EUCLID randomised 13,885 patients with peripheral artery disease to ticagrelor 90 mg twice daily or clopidogrel 75 mg daily. Patients were enrolled based on an abnormal ankle- brachial index ≤ 0.80 or a prior lower extremity revascularisation.

tiCagreLor In paD (EUCLID) trial, ticagrelor did not reduce the primary composite endpoint of cardiovascular mortality, myocardial infarction, or ischaemic stroke versus clopidogrel in patients with peripheral artery disease and a history of lower extremity revascularisation.

© AHA/Rodney White 2016

PRACTICEUPDATE CARDIOLOGY