Plaque imaging with CT—a comprehensive review on coronary CT angiography based risk assessment

After the first description of CT angiography (CTA) in 1992 (1,2), further technological advances, such as: more powerful X-ray tubes, faster gantry rotation times, multiple parallel detector rings and decreased slice thickness (3,4) were introduced, that allowed the visualization of the coronary arteries (5). Coronary CTA has emerged as a non-invasive alternative to invasive coronary angiography (ICA) for the diagnosis of obstructive coronary artery disease (CAD). With its excellent sensitivity and negative predictive value (6,7), coronary CTA is a robust diagnostic test to rule out severe coronary stenosis and is widely used as a “gate-keeper” for ICA (8,9). Nevertheless, modern CT scanners allow not only the visualization of the coronary lumen as ICA, but also the vessel wall, granting non-invasive analysis of atherosclerosis itself. This unique property of coronary CTA holds many advantages for patient risk stratification, that other non-invasive tests do not. Coronary CTA is currently also the only non-invasive imaging modality for the evaluation of non-obstructive CAD