The purpose of the study is to evaluate diagnostic performance of high iodine (iopamidol 370
mg/dl) content versus low iodine (iodixanol 300 mg/dl) content for diagnostic accuracy by
contrast-enhanced Coronary Cardiac Computed Tomography (CCTA) using a 64-detector-row CT
scanner for detection of presence or absence of coronary artery obstruction when compared
against invasive coronary angiography, the standard of truth.