A coronary angiogram is a procedure that uses X-ray imaging to see your heart’s blood vessels. The test is generally done to see if there’s a restriction in blood flow going to the heart. Coronary angiograms are part of a general group of procedures known as heart (cardiac) catheterizations. Cardiac catheterization procedures can both diagnose and treat heart and blood vessel conditions. A coronary angiogram, which can help diagnose heart conditions, is the most common type of cardiac catheterization procedure.