Acute coronary syndrome.

Abstract

Acute coronary syndromes encompass a heterogenous group of patients with different clinical presentations, who have differences in both the extent and severity of underlying coronary atherosclerosis and who have different degrees of risk of progression to myocardial infarction. For each patient, the pre-hospital practitioner should make individual treatment decisions based on the history and examination, the ECG findings, the facilities and diagnostic equipment available and the transfer time to the nearest appropriate hospital. Patients with acute ischaemic chest pain should have oxygen, aspirin, nitrates and opioid analgesia. A 12 lead ECG should be performed within 5 minutes of initial assessment. If the ECG reveals ST-segment elevation or presumed new LBBB, this signifies acute myocardial infarction and in most cases immediate reperfusion therapy should be considered. The evidence of benefit in terms of mortality and morbidity following prompt anti-platelet and fibrinolytic therapy in such cases is unequivable. Pre-hospital fibrinolysis is now well established and should be undertaken in patients with acute infarction on clinical and ECG grounds if the transfer to hospital is likely to exceed 30 minutes and it is less than 12 hours since the onset of pain. Patients with no ECG evidence of infarction may still be at considerable risk and should still be conveyed to the nearest appropriate medical facility. Whilst en-route, they should receive aspirin, nitrates, low molecular weight heparin (LMWH) and beta blockers provided there are no contra-indications.