Coronary CT angiography will not be performed on any patient with contraindication to IV contrast media. This includes patients with: 1) creatinine value of greater than 1.3 mg/dl, 2) history of multiple myeloma, 3) use of metformin-containing products less than 24 hours prior to contrast media, and 4) history of significant allergic reaction to CT contrast agents despite the use of premedication.