Heart disease affects millions of people in the United States and is the number one cause of death globally. There are many symptoms of heart disease including chest pain, shortness of breath, high blood pressure, and an irregular heart beat. Having these symptoms could lead to a doctor prescribing a nuclear stress test.
What is a Nuclear Stress Test?
A nuclear stress test uses thallium or sestamibi to measure the blood flow to your heart muscle when it is at rest and during stress on the heart. It usually involves taking two sets of images of the heart. One set of images is taken during an exercise test and another set is taken while a patient is lying down.
Why is it Performed?
A nuclear stress test gathers information about how well your heart works. A patient may be given a nuclear stress test if he or she is suspected of having coronary artery disease. A doctor may also use this test to look at the size and shape of the heart. A doctor can see if the heart is enlarged or measure the heart’s pumping function.
Why is used in the test?
At a certain point in the exercise test, the doctor or technician will inject a nuclear dye into the patient. This radioactive dye is called thallium or sestamibi (Cardiolite). This substance mixes with the patient’s blood and travels to his or her heart. Then, a special scanner, which detects the radioactive material, creates images of the heart muscle. Inadequate blood flow to any part of the heart will show up as a light spot on the images because not as much of the radioactive dye is getting there.
The test is then repeated anywhere from one to three hours later when the patient is completely rested. The dye is re-injected and the scanner takes images of the heart to determine blood flow, view heart size, and measure shape.
After the test
A technologist will compile the reports using a nuclear medicine software program. The reports will viewed a physician who will interprete the images will enter his/her findings and summarize the test. The nuclear medicine technologist will enter the dosing information and any results from processing the images. The doctor will schedule a time to meet with the patient to discuss his or her findings.
Results of the test
If a patient has normal results, then blood was flowing properly through the coronary arteries. All the images will look normal. If a patient has abnormal results, there was potentially reduced blood flow possibly due to a blocked or narrow artery. An abnormal result may result in a change in heart medication, stent placement or angioplasty, coronary angiograph or heart bypass surgery.