Nuclear medicine heart scan
Special information on this examination
As a rule, the myocardial scintigraphy helps your treating physician evaluate a possible undiagnosed heart attack or reduced blood flow caused by physical stress. Furthermore, after a heart attack one can detect the remaining tissue with a restricted function (hibernating).
This method will also be reasonable after bypass surgery, in order to confirm the openness of the bypasses. The examination has the advantage of providing a quick overview of the circulation without any larger intervention in the vascular system (coronary angiography).
As a rule, technetium-marked molecules, such as Tc-99m MIBI or tetrofosmin, are used as substances (radiopharmaceuticals) today. The activity applied is approximately 600 MBq per single examination administered as an intravenous injection.
For evaluation it is necessary to perform, first of all, an exercise-study (stress) and, at a second time (mostly on the next day), a rest study. During the exercise study, an internist will ask you to pedal a bicycle ergometer intensively under ECG control and monitoring. At the moment of the maximal stress the radiopharmaceutical will be injected into the vein.
On the day of examination itself you should take as few cardioactive medications as possible. Please discuss it with your referring physician. On the day of examination you should not eat anything at home. After administration of the substance you should have breakfast following the instructions of our personnel. The point of this breakfast is to completely remove the gallbladder fluid that temporarily stores a part of the radioactive substance.
Both during the exercise and rest study the images are made, for which purpose the head of the camera rotates around the chest (SPECT). The patient lies, as a rule, in the prone position. According to the patterns of activity distribution obtained in both studies, conclusions can be drawn regarding blood circulation.
The total examination time per each study can be between 1 and 4 hours.