Safety and Effectiveness of Visipaque 320mg-I/ml for Use in Contrast-Enhanced CT Angiography of Arteries of the Heart

Inclusion Criteria: * Subject is ≥18 years old. * Subject must have been referred for an elective coronary angiography for one of several specified conditions. Exclusion Criteria: * The subject has impaired renal function with a serum creatinine level ≥1.7 mg/dL (150 μmol/L). If the institution's practising guideline(s) regarding the serum creatinine limits for receiving radiologic contrast medium are lower than 1.7 mg/dL (150 μmol/L), the investigator should follow the practising guideline(s) of their institution. * Subject has a known allergy to iodinated contrast agent * Subject has atrial fibrillation/flutter or any irregular heart rhythm considered to interfere with temporal acquisition of cardiac CT images. * The subject's resting heart rate is 66-100 bpm and β-blocker therapy is contraindicated. * Use of nitroglycerin is contraindicated. * Subject has had a prior CABG procedure. * Subject has a metal cardiac stent in place or artificial heart valve(s). * Subject has had a prior pacemaker or internal defibrillator lead implantation. Subject must agree to discontinue metformin day of and for 48 hours after the CTA procedure.