What’s the Duration of a Nuclear (Thallium) Stress Test?

The nuclear stress test can show how blood flows through your heart muscles. This reveals how well the heart pumps blood and areas of your heart muscles that do not get enough blood.

Nuclear stress is an imaging test that shows how well blood flows into your heart when you’re exercising or at rest. This test is also known as myocardial perfusion imaging (MPI) or a thallium stress test.

This test is considered noninvasive, meaning it happens outside the body. It uses a small amount of a radioactive substance called a tracer, or radionuclide, that is injected into your veins.

Doctors perform nuclear stress tests for different reasons, such as to:

• find out whether a person‘s heart is healthy enough to manage physical activities
• check whether a person has had a heart attack or has other heart conditions, as well as whether there is damage from the condition
• to find out why a person is experiencing chest pain or other discomforts

Let’s discuss nuclear stress tests, how long they take to perform, and how to prepare for them.

The duration of nuclear stress tests varies but typically takes about 3 to 4 hours . Here is an overview of the steps that healthcare professionals perform during the test.

Injection

As you are resting, a medical professional will insert an intravenous (IV) line into a vein in your arm and inject the radioactive substance through it. Thallium is one of the most commonly used radioactive tracers.

The tracer will enter your bloodstream, and the dye will reveal the movement of blood through your body. It will then get absorbed in the heart within about 15 to 40 minutes.

At-rest scan

As you continue resting, usually lying on an X-ray table, a gamma camera scans your heart for small amounts of gamma radiation that the tracer emits and takes pictures.

Exercise

You may be asked to exercise to increase your heart rate. A medical professional will place blood pressure cuffs on your arm and electrodes on your chest to monitor your heart. They will have you increase the intensity and speed of your exercise until you reach a target heart rate. The exercise phase can take about 10 to 15 minutes, according to MedlinePlus.

If you are unable to exercise, you may be asked to use a medication to induce stress similar to that of exercise for about 10 to 20 minutes, per MedlinePlus.

Post-exercise injection

After the exercise, you will receive another radioactive tracer injection and wait for another 15 to 40 minutes for your heart to absorb the radioactive tracer.

Post-exercise scan

The professional performing your test may ask you to return to the X-ray table, where they will take pictures of your heart. They will monitor you for about 10 to 15 minutes until your heart rate returns to usual.