[2010, amended 2016] 1.3.3.7 Arrange blood tests to identify conditions which exacerbate angina, such as anaemia, for all people being investigated for stable angina. [2010] 1.3.3.8 Only consider chest X-ray if other diagnoses, such as a lung tumour, are 1.3.3.9 If a diagnosis of stable angina 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. 1.3.3.10 For people in whom stable angina cannot be excluded on the basis of the clinical assessment alone, take a resting 12-lead ECG as soon as possible after presentation. [2010, amended 2016] 1.3.3.11 Do not rule out a diagnosis of stable angina on the basis of a normal 1.3.3.12 Do not offer diagnostic testing to people with non-anginal chest pain on clinical assessment (see recommendation 1.3.3.1) unless there are resting ECG ST-T changes or Q waves. [2016] 1.3.3.13 A number of changes on a resting 12-lead ECG are consistent with CAD and may indicate ischaemia or previous infarction. These include: pathological Q waves in particular LBBB ST-segment and T wave abnormalities (for example, flattening or inversion). Note that the results may not be conclusive. Consider any resting 12-lead ECG changes together with people's clinical history and risk factors. [2010] 1.3.3.14 For people with confirmed CAD (for example, previous MI, revascularisation, previous angiography) in whom stable angina cannot be excluded based on clinical assessment alone, see recommendation 1.3.3.15 Consider aspirin only if the person's chest pain is likely to be stable angina, until a diagnosis is made. Do not offer additional aspirin if there is clear evidence that people are already taking aspirin regularly or are allergic to it. 