Myocardial perfusion scans (also known as nuclear stress tests) are imaging tests that evaluate the blood flow to the heart muscle (myocardium). The test is commonly used to assess for coronary artery disease (CAD), detect areas of the heart that may not be getting enough oxygenated blood, and determine the extent of damage caused by heart conditions such as heart attacks. This type of scan provides important information about the heart's ability to pump blood and its overall function.