Nuclear Stress Test
Nuclear Stress Test
A nuclear stress test uses radioactive dye and an imaging machine to create pictures showing the blood flow to your heart. The test measures blood flow while you are at rest and are exerting yourself, showing areas with poor blood flow or damage in your heart.
The test usually involves injecting radioactive dye, then taking two sets of images of your heart — one while you’re at rest and another after exertion.
A nuclear stress test is one of several types of stress tests that may be performed alone or in combination. Compared with an exercise stress test, a nuclear stress test can help better determine your risk of a heart attack or other cardiac event if your doctor knows or suspects that you have coronary artery disease.
How is the Nuclear Stress test Performed
It is done in stages:
You will have an intravenous (IV) line started.
- A radioactive substance, such as thallium or sestamibi, will be injected into one of your veins.
- You will lie down and wait for between 15 and 45 minutes.
- A special camera will scan your heart and create pictures to show how the substance has traveled through your blood and into your heart.
Most people will then walk on a treadmill (or pedal on an exercise machine).
- After the treadmill starts moving slowly, you will be asked to walk (or pedal) faster and on an incline.
- If you are not able to exercise, you may be given a medicine called a vasodilator (such as adenosine or Persantine). This drug widens (dilates) your heart arteries.
- In other cases, you may get a medicine (dobutamine) that will make your heart beat faster and harder, similar to when you exercise.
Your blood pressure and heart rhythm (ECG) will be watched throughout the test.
When your heart is working as hard as it can, a radioactive substance is again injected into one of your veins.
- You will wait for 15 to 45 minutes.
- Again, the special camera will scan your heart and create pictures.
- You may be allowed to get up from the table or chair and have a snack or drink.
Your provider will compare the first and second set of pictures using a computer. This can help detect if you have heart disease or if your heart disease is becoming worse.