 A myocardial perfusion scan during treadmill stress test is used to measure the heart's blood supply both during exercise and rest. If the stress scan looks normal, rest scan may not be performed. Pre procedure, do not consume caffeinated foods and please inform the doctor if you are pregnant. A 3 hour fast before the scan is advised. 24 hours before the procedure, don't take medications like statins, atin, metropolol, sorbitrate, etc. However, diabetic medications can be taken. During the procedure, an intravenous line will be placed and you will be asked to walk on a treadmill till the target heart rate is achieved. A small dose of radioactive injection is injected intravenous. During the peak exercise and scan is obtained after 45 minutes. After this, you will be asked to eat fatty foods before the stress scan. About 1 and a half hours after the scan, a second injection is given during rest and scan is obtained after 1 hour. Reports will be issued the same day.