What Happens during Myocardial Perfusion Imaging?
Myocardial perfusion imaging (MPI) typically involves Two stages: stress and rest imaging. During stress MPI, the goal is to assess blood flow to your heart muscle when it's working harder. This is often achieved through exercise on a treadmill, gradually increasing intensity until you reach your target heart rate. Alternatively, medication might be used to mimic the effects of exercise and increase heart rate in cases where exercise isn't feasible. A radioactive tracer will be injected into your bloodstream during the peak of stress. After a short rest period, a special camera will capture images of your heart muscle as it absorbs the tracer, revealing areas with adequate or reduced blood flow.
The second stage involves rest imaging. You'll lie comfortably on a table, and another dose of radioactive tracer will be injected. After a resting period, similar to stress imaging, a gamma camera will capture images of your heart muscle at rest. Comparing the stress and rest images allows doctors to identify any areas where blood flow is significantly reduced during stress, potentially indicating narrowed coronary arteries and decreased oxygen delivery to the heart muscle.
