ArticlesPrasugrel versus clopidogrel for patients with unstable angina or non-ST-segment elevation myocardial infarction with or without angiography: a secondary, prespecified analysis of the TRILOGY ACS trial
Introduction
Coronary revascularisation with percutaneous coronary intervention or coronary artery bypass grafting is recommended for patients with unstable angina or non-ST-segment elevation myocardial infarction (UA/NSTEMI).1, 2 However, many such patients are managed without revascularisation.3, 4 Patients who are not revascularised can be treated with drugs either with or without invasive assessment of coronary anatomy.
Treatment with two antiplatelet drugs is also a cornerstone of management of UA/NSTEMI. Based on the CURE trial,5 guidelines recommend dual antiplatelet treatment with aspirin and a P2Y12 antagonist as adjunctive treatment, irrespective of whether the treatment strategy includes coronary revascularisation. Subsequent trials, including TRITON–TIMI 386 and PLATO,7 have shown that more intensive P2Y12 antagonist treatment has greater efficacy for patients with UA/NSTEMI compared with a standard regimen of clopidogrel: most patients had coronary angiography and were treated with coronary revascularisation. In TRITON–TIMI 38, all patients with UA/NSTEMI were enrolled only after percutaneous coronary intervention was planned. In this population, prasugrel reduced cardiovascular death, myocardial infarction, and stroke more than clopidogrel, but with a higher risk of bleeding. However, in the Targeted Platelet Inhibition to Clarify the Optimal Strategy to Medically Manage Acute Coronary Syndromes (TRILOGY ACS) trial—in which patients were treated without planned revascularisation with or without pre-enrolment angiography at the discretion of the treating doctor—neither a significant reduction in cardiovascular events nor an increase in severe bleeding was reported.8, 9
We present results of a subgroup analysis of TRILOGY ACS, in which we assessed differences in patient characteristics, outcomes, and effects of prasugrel compared with clopidogrel based on whether or not patients underwent coronary angiography before enrolment.
Section snippets
Study design and procedures
TRILOGY ACS was a phase 3, randomised, double-blind, double-dummy, active-control study done at more than 800 sites worldwide (ClinicalTrials.gov number NCT00699998).9 The study was done in accordance with the Declaration of Helsinki, and national and local regulatory authorities approved the trial protocol in all participating countries and at all sites.
At enrolment, all participants were scheduled to be treated with drugs only without revascularisation. Patients were excluded if percutaneous
Results
The 7243 patients included in the primary study population were younger than 75 years (figure 1); of whom, 3085 (43%) were treated after angiography and 4158 (57%) were treated without angiography. The most common reasons for not having angiography were patient refusal (n=1322; 32%), unavailability of on-site angiography (n=1185; 29%), and either an unsuitable coronary anatomy or other contraindication (n=506, 12%); 1145 patients (28%) gave other or no reason.
In both groups (with or without
Discussion
Patients in the TRILOGY ACS trial who were treated after coronary angiography differed from those who did not have angiography with respect to baseline characteristics and clinical outcomes, as well as the benefit and risk of prasugrel.
The differences in baseline characteristics between groups probably contributed to the differences in clinical outcomes—higher rates of post-acute coronary syndrome events, but not events modifiable by antiplatelet drugs. The differences in event rates are
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Clopidogrel versus ticagrelor or prasugrel in patients aged 70 years or older with non-ST-elevation acute coronary syndrome (POPular AGE): the randomised, open-label, non-inferiority trial
2020, The LancetCitation Excerpt :Previous trials have shown the benefit of adding clopidogrel to aspirin in patients with acute coronary syndrome to reduce the risk of death, myocardial infarction, and stroke.16,17 Studies with the stronger P2Y12 inhibitors prasugrel and ticagrelor showed a further reduction of thrombotic risk compared with clopidogrel.3,4,18,19 However, these benefits were in part counterbalanced by an increased risk for major bleeding.
Selection of P2Y<inf>12</inf> Inhibitor in Percutaneous Coronary Intervention and/or Acute Coronary Syndrome
2018, Progress in Cardiovascular Diseases