A Cardiolite™ scan is a medical imaging study of the heart conducted to look for signs of ischemia, where blood flow is not reaching the heart muscle. Ischemia can cause damage to the heart and puts patients at risk of myocardial infarctions and other complications. In a Cardiolite™ scan, a radioactive tracer substance is injected and followed as it is absorbed by the heart. The radiation exposure is very low and the patient's body expresses it naturally after the test.
A doctor may order a Cardiolite™ scan if there is a concern about a patient's heart health. The goal is to look at cardiac perfusion, the distribution of blood in the heart muscle, both when the heart is at rest and when the heart is working hard. Medications can be used to induce cardiac stress or a patient can be used to use a stationary bicycle or treadmill to elevate the heart rate.
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In a Cardiolite™ scan, technetium Tc99m sestamibi is injected into the patient while the patient's heart rate is elevated with exercise or medications. Imaging equipment follows the tracer as it moves through the patient's bloodstream and into the heart. In a healthy patient, the heart will illuminate relatively uniformly, showing that the tracer is diffusing throughout the heart and indicating that blood is reaching all of the heart muscle. Dark spots indicate that blood is not reaching certain areas of the heart or is reaching them very slowly. The test is repeated with the patient at rest to compare resting and working data.
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The outcome of a Cardiolite™ scan can indicate if the patient has a heart condition causing ischemia and can also be used to learn more about the patient's heart health. Some patients may have dark spots on both tests, while others may only develop ischemia when the heart is under stress. Making modifications to diet and exercise may help to address the problem and there are also medications and other treatments available.
This test takes several hours to complete, or may be conducted as two separate tests over two days. Patients should ask about scheduling when the test is recommended to make appropriate plans and it is also advisable to ask if there are any special preparations to take before coming in for the test. Patients may find it helpful to bring some reading material, as there may be some waiting involved in settings where entertainment is not readily available.