A CT Coronary Angiogram (CTCA) is a test that visualizes the cardiac anatomy, coronary circulation and vessels. This provides information about blood vessel abnormalities such as narrowing, blockage and inflammation caused by calcified or noncalcified plaque. If you are experiencing symptoms such as chest pain, breathlessness, excessive sweating, irregular heartbeat or dizziness, your doctor may then refer you for this scan for early detection of heart disease.