Imaging the inside of coronary arteries (intravascular imaging) offers great insight into the assessment and treatment of coronary artery disease. Over time, substances such as fat, cholesterol and calcium can build up into 'plaques' in the arteries, causing narrowings or even blockages. These plaques can also rupture, causing cardiovascular events such as heart attacks or strokes. By using ultrasound and infrared technology, intravascular imaging can help assess these plaques, however this is an invasive technique involving angiography. Plaque composition, structure and stability can be affected by inflammation and the stress that the arteries are under. The investigators have pioneered novel minimally-invasive methods for modelling arterial stress using computed tomography coronary angiography (CTCA), as well as imaging coronary arterial inflammation using a positron emission tomography (PET) scan. Before embarking upon a large-scale clinical outcome study to determine whether these novel methods can improve risk prediction, the aim is to perform a proof-of-principle study to further develop our methodology for hybrid image analysis, and to validate this technique against high-resolution intravascular imaging as a surrogate marker of histology.

Inclusion Criteria

1. Age ≥40
2. Stable angina, defined as typical symptoms with evidence of reversible ischemia in non-invasive test and/or documented obstructive coronary artery disease on coronary angiography
3. Patient that is willing and can provide written informed consent.

Exclusion Criteria

1. Acute coronary syndrome within <3 months
2. Pregnancy
3. Estimated glomerular filtration rate (eGFR) <60ml/min/1.73m²
4. Previous bypass surgery
5. Decompensated heart failure, or left ventricular ejection fraction less than 30%
6. Patient allergic to contrast or cannot receive treatment with aspirin, heparin, or thienopyridines
7. Anticipated life expectancy <2 years
8. Flow limiting coronary artery disease in the proximal segments of all the 3 epicardial coronaries
9. History of heart transplantation
10. Patient that requires surgical revascularization
11. Extensive coronary artery disease (i.e., multiple chronic total occlusions) or tortuous coronary anatomy that does not allow assessment of the

Stable angina patients with known coronary artery disease referred for further invasive assessment as part of routine clincal care