A heart scan, also known as a coronary calcium scan, is a specialized X-ray test that provides pictures of your heart that can help your doctor detect and measure calcium-containing plaque in the arteries. Plaque inside the arteries of your heart can grow and restrict blood flow to the muscles of the heart. Measuring calcified plaque with a heart scan may allow your doctor to identify possible coronary artery disease before you have signs and symptoms. Your doctor will use your test results to determine if you may need medication or lifestyle changes to reduce the risk of heart attack or other heart problems.