The health care provider will inject a radioactive material called technetium into your vein. This substance attaches to red blood cells and passes through the heart.
Special cameras or scanners trace the substance as it moves through the heart area. The red blood cells inside the heart that carry the radioactive material form an image that the camera sees. The camera is synchronized with an electrocardiogram. Using computer software, the images are made to appear as if the heart is moving.
How to prepare for the test
You may be told not to eat or drink for several hours before the test.
How the test will feel
You may feel a brief sting or pinch when the IV is inserted into your vein, usually in the arm. You may have trouble staying still during the test.
Why the test is performed
The test will show how well the blood is pumping through different parts of the heart.
Normal results indicate that the heart squeezing function is normal. The test can check the overall squeezing strength of the heart (ejection fraction). A normal value is above 50 - 55%.
The test also can check the motion of different parts of the heart. If one part of the heart is moving poorly while the others move well, it may mean that there has been damage to that part of the heart, possibly from a blockage in the artery that delivers blood to that area.
Testing whether a medicine has affected heart function
What the risks are
Nuclear imaging tests carry a very low risk of complications. Exposure to the radioisotope delivers a small amount of radiation. This amount is safe for patients who only have an occasional nuclear imaging test.
Udelson JE, Dilsizian V, Bonow RO. Nuclear cardiology. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 17.
David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; and Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.