Matveeva A, et al. - Physicians designed this study to compare image quality, observer confidence, radiation exposure in the standard-dose (SD-CCTA) and low-dose (LD-CCTA) protocols of coronary CT angiography (CCTA) in patients with atrial fibrillation (AF). Radiation exposure could be decreased by 50% at the expense of 20% impaired image quality using a low-dose protocol in AF. While they recommended a standard-dose protocol for older patients and those suspected of having coronary artery disease (CAD), a low-dose CCTA protocol could be indicated in young patients.