[2010, amended 1.2.6.2 When a raised troponin level is detected in people with a suspected ACS, reassess to exclude other causes for raised troponin (for example, myocarditis, aortic dissection or pulmonary embolism) before confirming the diagnosis of ACS. [2010] 1.2.6.3 When a raised troponin level is detected in people with a suspected ACS, follow the NICE guideline on acute coronary syndromes until a firm diagnosis is made. Continue to monitor (see recommendation 1.2.3.4). 1.2.6.4 When a diagnosis of ACS is confirmed, follow the NICE guideline on acute coronary syndromes. [2010] 1.2.6.5 Reassess people with chest pain without raised troponin levels and no acute resting 12-lead ECG changes to determine whether their chest pain is likely to be cardiac. If myocardial ischaemia is suspected, follow the recommendations on stable chest pain in this guideline (see the section on people presenting with stable chest pain). Use clinical judgement to decide on the timing of any further diagnostic investigations. [2010, amended 2016] 1.2.6.6 Do not routinely offer non-invasive imaging or exercise ECG in the initial assessment of acute cardiac chest pain. [new 2016] 1.2.6.7 Only consider early chest computed tomography (CT) to rule out other diagnoses such as pulmonary embolism or aortic dissection, not to diagnose ACS. [2010] 1.2.6.8 Consider a chest X-ray to help exclude complications of ACS such as pulmonary oedema, or other diagnoses such as pneumothorax or 1.2.6.9 If an ACS has been excluded at any point in the care pathway, but people have risk factors for cardiovascular disease, follow the appropriate guidance, for example, the NICE guideline on cardiovascular disease and the NICE guideline on hypertension in adults. [2010] 1.3 People presenting with stable chest pain This section of the guideline addresses the assessment and diagnosis of intermittent stable chest pain in people with suspected stable angina. 