Nuclear Stress Testing
Diagnostic testing has advanced to such an extent that we now have the ability to observe the heart and its functions. Nuclear stress testing provides us with essential data that relates to how the heart behaves during rest and also after physical exertion.
What is Nuclear Stress Testing?
Nuclear stress testing is also referred to as a myocardial perfusion imaging. This test captures images of the heart after a mild, safe radioactive substance has been introduced into the bloodstream. The purpose of this non-invasive cardiac exam is to better understand the reason for symptoms such as shortness of breath or chest pain. The pictures that are taken of the heart show the chambers and how well blood is being pumped through them. The state of the heart muscle itself can be revealed during a nuclear stress test, enabling doctors to observe tissue damage and necrosis, if either are present.
Candidates for Nuclear Stress Testing
We recommend a nuclear stress test for patients who exhibit symptoms of coronary artery disease or who have been diagnosed with this condition. This test may also be a follow-up to electrocardiogram if abnormal results occurred during that test. Patients who are unable to walk on a treadmill may be good candidates for nuclear stress testing, as are high-risk patients such as smokers and diabetes.
Nuclear Stress Test process
If your doctor recommends a nuclear stress test, you may expect the following process:
Nuclear stress testing is similar to the exercise stress test in terms of equipment. We apply small metal discs (electrodes) to the chest and back. Each electrode has a wire that travels back to the electrocardiogram machine. After we apply these fixtures, you will walk on a treadmill.
After a brief walk on the treadmill, we will administer an injection of a radioactive substance, and you will lie on a table. Above the table will be a gamma-ray camera. This camera will capture images of your heart. More than that, the gamma-ray machine detects traces of the radioactive material in your veins for closer observation of heart function.
Following this portion of the nuclear stress test, the patient will spend a period of 3 to 4 hours resting. We will then instruct the patient on what foods and beverages with caffeine they should avoid, including chocolate and coffee. The patient should also not exercise during this time. After the prescribed time, the patient will return to the imaging center to have another round of pictures taken of their heart. This time, the radioactive material that we inject will facilitate imaging of their heart at rest.
What is the difference between a nuclear stress test and a stress test?
The main difference between nuclear stress testing and exercise stress testing is that exercise stress testing uses ultrasound to produce images of the heart. While nuclear stress testing uses a radioactive dye that is injected into the bloodstream and a gamma-ray camera captures the images of your heart.
What Results will the Nuclear Stress test show?
Nuclear stress testing provides doctors with valuable information that facilitates the diagnosis and treatment of heart conditions. A nuclear cardiac test can indicate how the heart is working during rest as well as exercise. The detection of radioactive material shows how well blood is circulating through the heart and its adjacent arteries. Doctors can measure if blood flow during times of stress is sufficient or if any part of the heart is not receiving adequate circulation. The absence of detection of radioactive material may indicate that a part of the heart muscle has died. Looking at images taken during a nuclear stress test, your doctor can observe:
- Heart chambers
- Blood flow through the heart
- Areas of damage to the heart muscle
- The state of coronary arteries, including narrowing or blockage
The data collected from a nuclear stress test helps doctors diagnose heart conditions. The test also facilitates the evaluation of current cardiac treatment.
Nuclear Stress Testing Risks
Nuclear cardiology testing has been widely used and is considered safe. However, there are a few risks presented by the procedure. These include:
- Allergic reaction to the radioactive substance
- Chest pain
- Arrhythmia, irregular heartbeat
- Blood pressure surge, during which blood pressure increases for a period of time
There is also a risk, though very small, that heart attack may occur as a result of nuclear stress testing.