Pharmacological Management
Antiplatelet Agent and Anticoagulants
Antiplatelet agents are considered a standard of care in patients who have experienced an MI, based on evidence from meta-analyses and randomized controlled trials.1
Oral anticoagulants may be used post-MI in a variety of different situations, but they are not a standard of care for all patients.
Evidence
The CURE trial, which was conducted in patients with non-ST-segment elevation acute coronary syndromes (ACS), showed that clopidogrel plus aspirin was significantly better than aspirin alone in preventing death from cardiovascular causes, non-fatal MI or non-fatal stroke.2
More recently, the TRITON and PLATO trials have shown that prasugrel and ticagrelor, respectively, have superior efficacy to clopidogrel when used in combination with aspirin following ACS.3,4 However, prasugrel has been associated with an increased risk of major bleeding compared with clopidogrel,3 and ticagrelor is not yet commercially available.
Recommendations
Unless there are contraindications, all patients who have had an MI should receive long-term therapy with aspirin 75-100 mg/day.1,5
In addition, the European Society of Cardiology (ESC) recommends treatment with clopidogrel 75 mg/day for 12 months in patients with STEMI or NSTEMI.1,5
Oral anticoagulants may be used instead of antiplatelet agents when the latter are contraindicated or not tolerated.1 Combination therapy with anticoagulants and antiplatelet agents is indicated in a number of situations:1
- when there is a specific indication for anticoagulation (e.g. atrial fibrillation, mechanical valve)
- in patients at high risk of thromboembolic events (in combination with aspirin only)
- in patients with recent stent placement and an indication for anticoagulation
Patients with an increased risk of bleeding should receive aspirin or clopidogrel, but not both, in combination with an oral anticoagulant. The target INR is 2-3, except in patients with an indication for anticoagulation, when the indication-specific INR should be used.1
References:
- van de Werf F, Bax J, Betriu A, et al. Management of acute myocardial infarction in patients presenting with persistent ST-segment elevation. The Task Force on the management of ST-segment elevation acute myocardial infarction of the European Society of Cardiology. Eur Heart J 2008;29:2909-45.
- The Clopidogrel in Unstable Angina to Prevent Recurrent Events Trial Investigators. Effects of clopidogrel in addition to aspirin in patients with acute coronary syndromes without ST-segment elevation. N Engl J Med 2001;345:494-502.
- Wiviott SD, Braunwald E, McCabe CH, et al. Prasugrel versus clopidogrel in patients with acute coronary syndromes. N Engl J Med 2007;357:2001-15.
- Wallentin L, Becker RC, Budaj A, et al. Ticagrelor versus clopidogrel in patients with acute coronary syndromes. N Engl J Med 2009;361:1045-57.
- Bassand J-P, Hamm CW, Ardissino D, et al. Guidelines for the diagnosis and treatment of non-ST-segment elevation acute coronary syndromes. The Task Force for the Diagnosis and Treatment of Non-ST-Segment Elevation Acute Coronary Syndromes of the European Society of Cardiology. Eur Heart J 2007;28:1598-660.