A thallium scan is an imaging test used to track the amount of blood reaching various areas of the heart. This is a nuclear imaging test because a radioactive tracer is used to map blood levels in different areas of the heart. The scan is precise, sensitive, and painless. In predicting cardiac problems, radioactive thallium has a significant predictive value.
Thallium scanning meets the demand for effective non-invasive techniques of diagnosing and assessing coronary artery disease (CAD). It is extremely sensitive for identifying CAD, forecasting outcomes, and determining the degree of ischemia.
The examination is generally divided into two parts. The stress scan is performed while your heart is actively functioning, and the rest scan is performed when your heart is at rest. The two scan sections are done on the same day.
The two scans are compared to see whether there are any variations that suggest areas of poor blood flow (which may cause chest discomfort) or no blood flow (due to a previous heart attack). A third section of the scan may be required for the following day. This can differentiate sections of the heart muscle that are not functioning but which nonetheless have a functional blood flow.
What is the purpose of a Thallium Scan?
After a heart attack, the scan identifies the size and location of the affected heart muscle. This allows the cardiologist to check the patient's cardiac cells and blood supply. The thallium scan is frequently used to assess persistent chest discomfort and abnormal ECG / EKG. It is also used to evaluate the activity of blood cells following bypass surgery.
What is the need for a Thallium Scan?
If your doctor recommends it, you may need a thallium scan. The test may be recommended by the doctor for the following reasons:
- Possible heart failure as a result of stress, chest pain
- Heart disease
- Previous history of heart disease.
- Determine the heart's status after surgery.
- To assess the efficacy of a drug
What happens during a Thallium Scan?
You will be asked to lie down on a table, and a little quantity of thallium (a radioactive tracer) will be injected into a vein in your arm. Then, a skilled professional uses a special camera to collect photographs and quantify the amount of radioactive tracer in your bloodstream as it travels to your heart.
How is a thallium scan performed?
During the scan, the technician uses a gamma camera to trace the injected radioactive tracer (thallium). The tracer will be picked up by the regions of your heart that receive a good blood flow, whereas areas with insufficient blood supply will appear as dark areas (cold spots) on the scan. Scan will be performed while lying on the bed and then exercising.
Thallium scanning is considered safe and poses very little harm to health. Thallium is a radioactive element that will be used as a radioactive tracer in this scan. A little quantity of this element is injected into the body via the arm vein. It is then transferred to the heart via blood.
Once some time has passed, a camera measures the quantity of thallium in the circulation of cardiac blood arteries. Pictures are evaluated on a computer to determine where there is an adequate and inadequate flow of blood in the heart. The tracer is absorbed by the portion of the heart that receives a decent supply of blood, whereas black patches develop in the region that does not receive enough blood. This allows the doctor to pinpoint the troublesome area of the heart.
The thallium scan procedure is painless, and the patient can resume normal activities on the same day as the test. In general, all radioactive substances are expelled from the body through urine in a maximum of two days. Therefore, it is essential to drink enough water and consume plenty of fluids such as coconut water, fruit juices, and so on to flush out toxins from the body readily. If any of the adverse effects linger for more than a week, see a doctor to address the issue.
The doctor advises avoiding eating or drinking for at least 2 hours before the thallium scan. If you must eat anything, choose meals that are easy to digest and do not make you feel bloated. 24 hours before the test, abstain from alcohol, smoke, aerated beverages, caffeine, and over-the-counter drugs. Diabetes sufferers must notify their doctor about the condition ahead of time. Additionally, inform the doctor about any drugs to which you are allergic.
How to Prepare for the scan?
The preparation that is necessary for a heart scan depends on the approach that will be utilized for the stress component. Thus it is vitally crucial that you follow the exact directions that you are given by the department where you have your scan.
Is there any risk of this scan?
No, there is no risk of a thallium scan, it is completely safe.
Understanding the Thallium Scan Test Outcomes
The test result assists the doctor in determining blood flow to the heart. The medical practitioner will evaluate the results of your scan to discover any coronary occlusions or other cardiac issues (if any).