What is a myocardial perfusion scan?
A myocardial perfusion scan uses a small amount of dye (a radioactive medium which is visible under x-ray) to see how well blood flows to the muscles of the heart (the myocardium).
A myocardial perfusion scan can be used to try to find the cause of unexplained chest pains. It can also show blood flow patterns to the heart walls, reveal whether the coronary arteries are blocked and determine the extent of injury to the heart following a heart attack.
What happens during a myocardial perfusion scan?
The myocardial perfusion scan can be carried out while resting, after gentle exercise, or on two separate occasions to compare resting and exercising.
In an exercise test, patients may be given medication that makes the heart beat faster and stronger. In some instances, people find that this gives them a tingling feeling in the chest or a sensation that their heart is beating strongly (palpitations). These sensations usually pass shortly after the test is over. When the heart is beating at a certain rate the dye is injected, usually into the hand. Several images are taken soon after the dye is injected. The absorption of the chemical in the blood vessels can be seen on the scan, and darker images represent areas with insufficient blood flow.