An intracameral or intracavitary course for a coronary artery is a rare anomaly. Nevertheless, it carries a significant impact for invasive cardiac procedures that require right atrial catheterization, pacemaker implantation, or electrophysiologic study such as radiofrequency ablation. If a coronary artery were to be damaged within the atrial chamber by catheter manipulation at the time of heart catheterization, serious complications might ensue. We describe the first reported case of an intracameral right coronary artery identified with multidetector 64-slice coronary computed tomographic angiography performed prior to pulmonary venous antral isolation for atrial fibrillation.