Randomized Trial Comparing the Effects of Ticagrelor Versus Clopidogrel on Myocardial Perfusion in Patients With Coronary Artery Disease

BackgroundTicagrelor is a P2Y12 receptor inhibitor used in acute coronary syndromes to reduce platelet activity and to decrease thrombus formation. Ticagrelor is associated with a reduction in mortality incremental to that observed with clopidogrel, potentially related to its non–antiplatelet effects. Evidence from animal models indicates that ticagrelor potentiates adenosine‐induced myocardial blood flow (MBF) increases. We investigated MBF at rest and during adenosine‐induced hyperemia in patients with stable coronary artery disease treated with ticagrelor versus clopidogrel. Methods and ResultsThis randomized double‐blinded crossover study included 22 patients who received therapeutic interventions of ticagrelor 90 mg orally twice a day for 10 days and clopidogrel 75 mg orally once a day for 10 days, with a washout period of at least 10 days between the treatments. Global and regional MBF and myocardial flow reserve were measured using rubidium 82 positron emission tomography/computed tomography at bas...