A MUGA scan, or Multiple Gated Acquisition scan, is an imaging study that assesses the function of the heart.  Radio-labelled red blood cells that are injected into the blood emit radiative energy that a camera can detect, creating an outline of the chambers of the heart and eventually a movie of the beating heart.   It is used to differentiate between functional and non-functional heart tissue in cases where a CABG or angioplasty may be needed and to assess ejection fraction (a measure of heart functionality).  

Pre-Study Details:

Your physician will give specific instructions before the study, and you should not eat after midnight before the study.  Allergies will be discussed, as you will receive an injection of radioactive substance.  Medication use will be discussed with your physician prior to the study.  

Study Details:

A technician will take you to a special injection room, where red blood cells that are labelled with radioactive technietium-99 are given through an IV and then you will wait for 30-90 minutes for the substance to accumulate in the body's tissue.  During this time, you will rest quietly.  The scanning begins after this rest period.  The gamma camera is pointed at the heart, gathering low-level radiation emissions and creating an outline image of blood flow through the heart.  

Post-Study Details:

Once the scan is complete, you will be done with the study.  There are usually no restrictions to daily activities and you should drink plenty of fluids to "wash out" the radioactive substance.  It usually takes a few days for the results to be interpreted.