A myocardial perfusion scan is a medical imaging test that evaluates blood flow to the heart muscle. It helps doctors assess how well the heart is receiving blood, which is crucial for diagnosing conditions like coronary artery disease. The test typically involves injecting a small amount of radioactive material and taking images of the heart at rest and during stress. During the scan, patients may exercise on a treadmill or receive medication to simulate exercise. The images produced show areas of the heart that may not be getting enough blood, helping guide treatment decisions and monitor heart health over time.