PRogression of Atheroma Evaluated by CT Angiography and IntraCoronary Imaging tEchniques

This is a combined cohort study with retrospectively and prospectively enrolled patients. Subjects with CAD detected by coronary CTA are consecutively enrolled. All the patients will undergo clinical follow-up for up to 5 years. Repeat coronary CTA will be conducted after 2 years. For patients referred to invasive coronary angiography, intracoronary imaging techniques, such as intravascular ultrasound (IVUS), optical coherence tomography (OCT), and near infrared spectroscopy (NIRS) will be performed. For all the prospectively enrolled patients, plasma and serum blood samples will be collected.

The purpose of this study is to investigate the natural history of coronary atherosclerotic plaques in this population. Comprehensive morphological plaque analysis will be performed to evaluate total atheroma volume (TAV), percent atheroma volume (PAV), plaque composition, high risk plaque features, and characteristics of perivascular adipose tissue (PVAT). Functional analysis will also be conducted to calculate hemodynamic parameters such as wall shear stress (WSS), oscillatory shear index (OSI), relative residence time (RTT), transverse WSS (transWSS), axis plaque stress (APS), fractional flow reserve (FFR), and δFFR across lesions. The associations of these morphological and functional parameters with plaque progression and the onset of major adverse cardiovascular events (MACEs) will be analyzed. In addition, the impact of pharmacological treatments and the levels of cardiometabolic factors on coronary plaque progression will also be investigated.

In the subpopulation who also receive intracoronary imaging examinations, intracoronary imaging modalities will be used to refine the inner and outer vessel contours, improve the accuracy of plaque composition characterization, and aid in the discovery of novel high-risk plaque features by coronary CTA.

Inclusion criteria

• Age ≥ 18 years
• Clinically significant angina pectoris, or suspected CAD
• Receive coronary CTA scan, with a visible plaque (defined as ≥25% diameter stenosis) in major coronary arteries.

Exclusion criteria

• Unsuitable for coronary CTA (such as severe renal impairment, uncontrolled thyroid condition, allergic to iodine, etc.)
• Receive percutaneous coronary intervention (PCI) within 6 months
• Prior history of myocardial infarction or heart failure
• Prior history of percutaneous coronary intervention (PCI) or coronary artery bypass graft (CABG)
• Abnormal liver function (serum alanine aminotransferase [ALT] level exceeding 3 times the upper limit of normal) or abnormal kidney function (eGFR ≤30 ml/min)
• Familial hypercholesterolemia
• Estimated survival ≤ 1 year
• Malignant tumor
• Pregnant or lactation, or have the intention to give birth within one year
• Poor coordinance, unable to follow-up