Nuclear Cardiology FAQs

My doctor has asked me to undergo a nuclear stress test. What does this involve?

A nuclear stress test is a diagnostic test to diagnose the presence of coronary artery disease, or narrowing of the arteries of your heart. This test if often performed in patients who have symptoms which suggest the presence of heart disease, or sometimes even in the absence of any symptoms if your doctor suspects that there is a possibility of this condition. This test is also performed in patients with known heart disease to monitor the favorable effects of treatment and progress of the heart condition.

What is a nuclear cardiologist?

A nuclear cardiologist is a physician who has been trained and qualified to perform and interpret nuclear cardiology studies. These physicians may have certification in cardiology, internal medicine, nuclear medicine, radiology or other related fields, with special training in nuclear cardiology and cardiovascular imaging.

What training is involved/required for doing a nuclear test?

ASNC, in cooperation with the American College of Cardiology, has developed guidelines for physician training in nuclear cardiology. These are available on the ACC and ASNC websites by clicking here. Another valuable document is ASNC's statement on physician training titled The Knowledge Base for Nuclear Cardiology Training. ASNC also has guidelines on training recommended for technologists perfoming nuclear cardiology procedures, available on the ASNC website.

What is a nuclear test, exactly?

A nuclear diagnostic test involves organs of the body and not specifically the heart. It will involve the injection of radiopharmaceuticals (radioactive elements) into the body and then later imaging that particular organ of interest. For the heart, these tests are performed to diagnose the presence of coronary artery disease, to assess the severity of coronary artery disease and to determine the squeezing power of the heart (ejection fraction). Terms used for cardiac nuclear tests include myocardial perfusion imaging and radionuclide scan, Cardiolite stress test, Myoview stress test, RNV; cardiac blood pooling imaging; nuclear heart scan; radionuclide ventriculography; and MUGA.

How can I be sure that my nuclear test is done by qualified professionals?

By asking the physician, the nurse and the technologist in the lab what qualifications they have to be able to perform a particular study. That includes but is not limited to board certification, examinations taken, credentials, etc. See the discussion of Frequently Asked Questions on certification in nuclear cardiology for physicians and advanced certification in nuclear cardiology for technologists.

Is this a dangerous test?

The risk of any adverse event such as a heart attack or death during a nuclear stress test is extremely small. To ensure your full safety, this test is performed in laboratories that are fully equipped to very carefully monitor patients during the test and to detect and treat any abnormal conditions that may develop during the course of testing. In order to minimize the risk of any adverse event during the test, the nuclear stress test starts with a brief interview and physical examination by a physician or a nurse and recording your medications ( both your heart medications and all other medications).

What are radiotracers, exactly, and are they dangerous?

Radiotracers, also commonly termed radiopharmaceuticals, radionuclides or radioisotopes, are low-level radioactive materials which emit radiation or gamma rays which can be imaged with specialized equipment known as a gamma camera. These agents are injected into the body so that a nuclear scanner or camera can take pictures. Sestamibi, Tetrofosmin and thallium are radiotracers commonly used in nuclear tests of the heart. Performed by qualified professionals, tests with radiotracers are safe and effective. The dosages used in nuclear cardiology are very small and well within the limits of safety as determined by NRC (Nuclear Regulatory Commission), the agency which monitors the use of radioisotopes in medical practice. Pregnant women should not have a nuclear test because potential effects on the unborn fetus have not been conclusively determined. If you are pregnant or think you may be pregnant, you should let your doctor know about this before a test is done.

How can I be sure that my nuclear test is done in a qualified lab?

As with the question on testing by qualified professionals, with regard to the facility, the patient should ask for confirmation that the laboratory has been accredited recently by a recognized accrediting body. The Joint Commission on the Accreditation of Healthcare Organizations (JCAHO) has a website with tools to help you make an evaluation of the laboratory you're considering and the Intersocietal Commission on the Accreditation of Nuclear Medicine Laboratories (ICANL) lists all facilities accredited by ICANL.

Are nuclear tests considered invasive?

No, a nuclear test involves only a needle stick and is not considered an invasive procedure.

Are there different kinds of nuclear scans?

Yes, nuclear scans are done for many different organs, such as kidneys, heart, lungs or thyroid glands. Each scan is done in a different way. For heart, there are different kinds of scans and different ways of doing them (called "protocols") depending on the patient's medical status, history and information desired from the test.

What is a stress test and why is it done?

A stress test may consist of an exercise, usually on a treadmill, or a "drug simulated" stress, which uses drugs such as adenosine, dipyridamole or dobutamine. These tests are done to evaluate patients with documented or suspected heart disease. A stress test also helps in the detection of heart disease which may not be producing any symptoms.

What preparation is needed before I come for the stress test?

You will be provided with instructions either by by your physician or by the staff from the nuclear cardiology laboratory when an appointment is made for a stress test. In general, you will be asked to come fasting in the morning. You will also be asked to avoid drinks containing caffeine (coffee, tea, cola drinks, chocolate or foods containing chocolate) for 24 hours prior to your stress test. If you have diabetes and cannot remain fasting for that long, let the stafff know about this and follow their instructions about your diabetes medications and light meal in the morning. You should bring a list of all your medications. Whether you should stop some of the medications before the stress test and whether your should take the morning dose of your medications depends upon the nature of medications and the practice of individual nuclear cardiology laboratories. You should follow their instructions in this regard.

Who gets a nuclear scan of the heart?

A nuclear stress test of the heart should be requested by a qualified physician who is practicing medicine. Indication to have a nuclear stress test of the heart is primarily based upon the judgement of your doctor that you need this test. This test is needed if your doctor thinks that you may have heart disease based upon your symptoms or presence of some conditions which predispose an individual to heart disease (such as high blood pressure, diabetes, high cholesterol, smoking and a family history of heart disease).

Can I ask for a nuclear stress test myself?

No, this test has to be ordered by your physician. If you are concerned about heart disease or think you may have heart disease and want to have a nuclear test, you should discuss this with your doctor. He or she will order this test if he thinks this is an appropriate test for you.

Why are nuclear cardiology procedures performed?

Nuclear scans are done in two circumstances: [1] to determine if heart artery blockages are present (coronary artery disease) in patients who have developed symptoms that suggest the possibility of heart trouble, such as chest pressure, or burning, or who are at significant risk of heart trouble (persons with diabetes or high cholesterol, for example), or [2] among patients with known heart trouble to determine their risk of an event in the future. That is, if a person has had a heart attack but a follow-up scan is normal or only mildly abnormal, the risk of another heart attack is low. However, a significantly abnormal scan would indicate an increased risk of another heart attack. If this were the case, the doctor would generally recommend a heart catheterization to determine what could be done to prevent such an event, for example, by coronary bypass surgery, angioplasty or stenting.

My doctor has recommended a nuclear stress test for me. Does this mean I have a heart problem?

Not necesarily. The test is often ordered if there is any suspicion of heart disease based upon your physician's assessment. This is similar to ordering a mammogram in women beyond the age of 40 years or a colonoscopy beyond the age of 50 years. Sometimes a stress test is ordered to exclude heart disease in persons enageged in certain professions such as commercial airline pilots, fire fighters etc.

What information does a nuclear stress test provide?

A nuclear stress test provides information related to the physiology of your heart. The test results can show the damaged areas of the heart and provide information about the narrowing or blocking of the arteries of your heart. This information is useful for predicting of the likelihood of an adverse cardiac event (such as a heart attack, need for a cardiac bypass surgery or risk of dying from heart disease) in future. Based upon the results of a nuclear stress test of the heart, your physician will be able to recommend options for treatment, if necessary.

Where is the nuclear stress test of the heart given?

The nuclear test is performed in a nuclear medicine or a nuclear cardiology laboratory. It could be in a hospital or in an outpatient setting in your physician's office. The procedure can be safely performed in either setting.

How long does it take?

The test normally takes from two hours to four hours. This depends on what protocol is most appropriate for any particular patient. In some cases, the test requires two sets of images to be obtained on two separate days. On each day it takes about 1.5-2.0 hours to complete the test.

What if the doctor finds a problem with my heart?

The doctor who ordered the test will receive the results of the test. If the results indicate a problem with your heart, he or she will discuss the test result with you and recommend the treatment options. A wide variety of treatment options are currently available. These options include treatment with medications, angioplasty or heart bypass surgery. The choice of a particular treatment option or a combination of options depend upon several factors. An important factor is the severity of abnormality seen on the nuclear stress test. Your doctor will discuss these options with you.

What kind of problems can this test can find?

Several problems may be identified by a nuclear stress test. Usually a heart test is performed to detect the presence of coronary artery disease, commonly called heart disease, or if there is any problem with blood flow to your heart muscle. This test can also show the area of the heart muscle damaged by previous heart attacks. This test also provides information about the squeezing power of your heart muscle. This is described by a number, designated as ejection fraction. Normal ejection fraction is 50% or above. An ejection fraction of 45-50% is considered borderline impairment of the squeezing power, whereas an ejection fraction below 45% is abnormal. If there is a problem with the amount blood going to the heart muscle you may need to be further evaluated by your doctor who will decide what the next step is.

Does my health insurance cover a stress test?

Yes, all health insurance plans in the United States should cover nuclear cardiology tests.

What is the difference between nuclear cardiology and cardiac PET?

Cardiac PET (Positron Emission Tomography) is actually a type of nuclear test of the heart. There are several methods and techniques for imaging the heart with nuclear technology. PET is one of them. Depending on the clinical question asked, a particular imaging modality, or type of test, would be preferred. PET scans are sometimes performed in patients with markedly weakened hearts.

Will I get the result after my nuclear stress test is over?

The stress test report is sent to your doctor, who is the best person to explain to you the results of this test.

How long will it take before my doctor gets the result of this test?

In most laboratories in the USA, the nuclear stress tests are interpreted by a physician by the end of the day or by the next morning. The test results are often conveyed to your doctor by mail/fax or electronically by the next day, depending upon the local practice. If a test report is needed urgently, your physician or his office can call the nuclear cardiology laboratory to get the test result sooner.

Can I get a copy of my nuclear stress test result?

Yes, you can ask for a copy of the nuclear stress test report to be sent sent to you. However, these reports are oftern full of medical terminology and technical jargon. It is best that this report be explained to you by your physician.

I had an angioplasty done on my hearrt 2 months ago. Now I am doing well. I have no complaints, but my doctor wants me to undergo a nuclear stress test. Why does he want me to undergo this test?

There may be several reasons for this test. In some cases, the remaining heart arteries may also have some degree of blockage. The long term treatment of these blocked arteries depends upon whether these interfere with blood flow to the heart muscle on a nuclear stress test. In some cases the artery where angioplasty is done tends to become narrowed again over time. This condition is called restenosis. Restenosis can usually be detected by a nuclear stress test. Your doctor can explain the exact reason for asking for a nuclear stress test in your case.