Management of acute coronary syndromes clinical guideline

This guideline describes the recognition and management of unstable angina (UA) and non-ST-segment elevation myocardial infarction (NSTEMI). These are two of the three components of the acute coronary syndrome (ACS). These forms of ACS most often arise from erosion or rupture of coronary atherosclerotic plaque and subsequent thrombus formation causing incomplete coronary occlusion. The term ACS, as used in this guideline, refers to these two components only. The third component, not discussed here, is ST-segment elevation myocardial infarction (STEMI), which is most frequently associated with complete coronary occlusion. ACS is a clinical emergency requiring urgent assessment. It is characterised by chest pain, ST-segment changes in the electrocardiogram (ECG) and a rise in the serum markers of myocardial injury/infarction. ACS encompasses a variety of clinical presentations. Risk stratification is essential to enable triage of patients to the optimal level of care and specific therapy. Careful clinical assessment is the cornerstone of this risk stratification. The pharmaceutical treatment of ACS is directed primarily at the dissolution of the developing intracoronary thrombus by antiplatelet (aspirin and clopidogrel) and anticoagulant therapy (heparin), and secondarily to the relief of symptoms by anti-anginal and analgesic medications. Low-molecular-weight heparin (LMWH) is at least as effective and safe as standard intravenous unfractionated heparin (UH). Coronary angiography is advised for all high-risk patients and those in whom reversible ischaemia or left ventricular dysfunction is discovered. The need for coronary revascularisation is dictated by the findings at angiography. In high-risk patients, appropriate, early revascularisation is recommended in preference to standard medical therapy and 'ischaemia-driven' revascularisation. The glycoprotein IIb/IIIa (GPIIb/IIIa) inhibitors should be used in association with percutaneous coronary intervention (PCI) in high-risk patients. All patients with ACS should receive secondary preventive treatment. It is imperative that they stop smoking. Dietary modification, physical rehabilitation, long-term low-dose aspirin use, b-blockade for those diagnosed with myocardial infarction, tight control of blood pressure, cholesterol lowering with a statin, and treatment with an angiotensin-converting enzyme (ACE) inhibitor should be prescribed.