Antithrombotic treatment and late management after myocardial infarction
THE CONTEXT
This passage describes platelet inhibition and anticoagulation in acute coronary syndromes, followed by the main components of longer-term care after myocardial infarction.
IIb/IIIa receptor antagonists
•
Tirofiban and abciximab block the final common pathway of platelet aggregation and strongly inhibit platelet-rich thrombus formation.
•
They are particularly beneficial in high-risk patients undergoing percutaneous coronary intervention, especially with a high angiographic thrombus burden or inadequate prior antiplatelet treatment.
Anticoagulation
•
Anticoagulation reduces thromboembolic complications and prevents reinfarction when reperfusion is not given or after successful thrombolysis.
•
Options include unfractionated heparin, low-molecular-weight heparin and pentasaccharides. Subcutaneous fondaparinux is given at 2.5 mg daily; subcutaneous enoxaparin at 1 mg/kg twice daily is a reasonable alternative.
•
Comparative trials favour pentasaccharides for safety and efficacy.
•
Anticoagulation should continue for 8 days or until hospital discharge or completion of coronary revascularisation.
•
A period of oral anticoagulation should be considered with persistent AF or extensive anterior infarction with mural thrombus because systemic thromboembolism risk is increased.
Late management
•
Longer-term care includes risk stratification, further investigation, rehabilitation, weight control, a lipid-lowering Mediterranean diet, smoking cessation and regular exercise.
•
Secondary prevention includes antiplatelet therapy with aspirin and/or clopidogrel, an ACE inhibitor or angiotensin receptor blocker, a statin, and treatment to control diabetes and hypertension.
•
The list also includes mineralocorticoid receptor antagonists. β-blocker use is qualified by the footnote restricting it to patients with left ventricular systolic dysfunction.
•
An implantable cardiac defibrillator is listed for high-risk patients.