What is safer, a coronary angiogram or CT angiogram?

In simplest terms the CT angiogram would be safer than a coronary angiogram. However, they are usually used in different circumstances. The CT angiogram is useful as a screening tool to see if coronary disease is present. A cardiac catheterization is performed when a patient has an acute coronary syndrome or a myocardial infarction to evaluate coronary disease, or even treated.