[2010] 1.2.4 Assessment in hospital for people with a suspected acute coronary syndrome 1.2.4.1 Take a resting 12-lead ECG and a blood sample for high-sensitivity troponin I or T measurement (see the section on use of biochemical markers for diagnosis of an acute coronary syndrome) on arrival in 1.2.4.2 Carry out a physical examination to determine: haemodynamic status signs of complications, for example, pulmonary oedema, cardiogenic shock and signs of non-coronary causes of acute chest pain, such as aortic dissection. 1.2.4.3 Take a detailed clinical history unless a STEMI is confirmed from the resting 12-lead ECG (that is, regional ST-segment elevation or presumed new LBBB). Record: the characteristics of the pain other associated symptoms any history of cardiovascular disease any cardiovascular risk factors and details of previous investigations or treatments for similar symptoms of chest 1.2.5 Use of biochemical markers for diagnosis of an acute coronary syndrome 1.2.5.1 Do not use high-sensitivity troponin tests for people in whom ACS is not 1.2.5.2 For people at high or moderate risk of MI (as indicated by a validated tool), perform high-sensitivity troponin tests as recommended in the NICE diagnostics guidance on myocardial infarction. [2016] 1.2.5.3 For people at low risk of MI (as indicated by a validated tool): perform a second high-sensitivity troponin test as recommended in the NICE diagnostics guidance on myocardial infarction if the first troponin test at presentation is positive. consider performing a single high-sensitivity troponin test only at presentation to rule out NSTEMI if the first troponin test is below the lower limit of detection 1.2.5.4 Ensure that patients understand that a detectable troponin on the first high-sensitivity test does not necessarily indicate that they have had an 1.2.5.5 Do not use biochemical markers such as natriuretic peptides and high- sensitivity C-reactive protein to diagnose an ACS. 