What is Nuclear Cardiology?

Nuclear cardiology is a method of producing images of the heart using a small injection of a radioactive material. These tests are used to asses the function or the blood perfusion to the heart.

The most likely candidates for nuclear cardiology are patients who have single or multiple risk factors for coronary artery disease. These risks include but are not limited to: chest pain, shortness of breath, hypertension, Positive family history, abnormal ECG's, and high cholesterol.

All nuclear cardiology results are analyzed by a physicians who has had special training in the interpretation of nuclear cardiology images.

What will Nuclear testing reveal

• if there is adequate blood flow to the heart muscle during increased levels of activity.
• the likelihood of having coronary artery disease and the need for future tests.
• the effectiveness of medical therapy and your cardiac treatment plan.

What tests will be performed

1. Dual Isotope Stress Test
2. Exercise Stress Test
3. Myoview Stress Test

1. Dual Isotope Stress Test

A diagnostic study that uses a small amount of radioactive material injected into the vein in order to image the heart using a special camera called a gamma camera. This test allows the physician to determine if there is adequate blood flow to the heart at rest, as compared with activity.

How to Prepare

• Do not eat or drink anything for 5 hours before the test.
• Do not drink or eat caffeine products (cola, mountain dew, chocolate products, coffee, or tea) for 24 hours before the test. Caffeine will interfere with the results of the test.
• Do not take over-the-counter medications that contain caffeine for 24 hours before the test.Ask your doctor what prescription medications should be taken on the day of your test.
• Do not discontinue your medications without first talking to your doctor. If you use an inhaler for breathing, bring it with you on the day of the test. If you are diabetic, ask your physician how to adjust your medications the day of the test. If you own a glucose monitor, bring it with you to check your blood sugar levels before and after the test. If your blood sugar levels are abnormal, tell the lab personnel immediately.
• Wear comfortable clothes and shoes suitable for walking. Women should wear a bra.

What to expect

A nuclear medicine technologist will explain the test and start an IV in your arm or hand. The technologist will inject a small amount of Thallium into the IV. Thallium is a radioactive isotope that allows the physician to assess the blood perfusion to your heart. After the injection, there is a brief wait and then you will be asked to lie very still under a camera for 15 to 20 minutes. These images will allow the physician to assess the blood flow to each area of the heart muscle at rest.

Next you will go to the stress area of thelaboratory. A technician will clean 10 small places on your chest and place a small electrode in each of the areas. Men may expect to have their chest shaved in these areas to help the electrodes stick. The electrodes are attached to an electrocardiograph (ECG) monitor, which allows the technician to monitor your heart's electrical activity during the stress test.

The physician will perform a baseline ECG and check your resting heart rate and blood pressure. The treadmill will start off slowly and will increase in speed and incline every 3 minutes.

If you are unable to walk on the treadmill, you doctor may order you to have the stress test done with medication. Adenoscan or Dobutamine can be used in place of the treadmill and will provide your physician with the same information about the blood flow to your heart.

At regular intervals the lab personnel will ask you how you feel. Please inform them if you experience the following: chest pain, jaw pain, arm pain, shortness of breath, dizziness, or if you become lightheaded. It is normal for your heart rate, blood pressure and breathing rate to increase during the test. The lab personnel will monitor you for any symptoms or changes on the ECG that suggest the test should be stopped. Your blood pressure and ECG will be recorded at various intervals during the test.

One minute before you stop exercising, the nuclear technologist will give you another injection of a radioactive tracer called Myoview (a different radioactive isotope). This will allow the physician to visualize the blood perfusion to your heart during exercise.
After your stress test, the lab personnel will monitor your blood pressure and ECG until they return to normal levels.

About 20 minutes after you have finished exercising, you will lie back under the camera for an additional 15 - 20 minutes.

A qualified nuclear cardiologist will review your test and will send your physician the results of the test.

Expect for your test to last somewhere between 2-4 hours. Ask your physician if you have any questions about your Dual Isotope Stress Test.
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2. Exercise stress test

Electrocardiography (EKG, ECG) is a test done to record the electrical activity of the heart. Exercise electrocardiography (usually called a stress or treadmill test) is electrocardiography done during exercise to evaluate how the heart responds to the demands of physical activity.

The test will determine the severity of heart disease and the ability of the heart to tolerate exercise in people with known heart disease or in those who have had a heart attack or heart surgery. On the basis of this information, a cardiac rehabilitation program, including appropriate exercise as well as a plan for low-risk daily physical activities, can be developed.

The test also identifies abnormal heart rhythms when symptoms such as dizziness, fainting, or palpitations occur during exercise or activity.

In addition, the test will screen for CAD in a person without symptoms, especially if the person has risk factors for CAD.

Physicians will provide the test after angioplasty, to see whether a blockage or narrowing of an artery has recurred, especially if chest pain (angina) or other symptoms have returned.

Some physicians will test to evaluate the effectiveness of certain medications or other therapy for irregular heartbeats (arrhythmias) or chest pain (angina).

How To Prepare

• You should not eat, smoke, or drink alcohol or caffeinated beverages for 2 to 4 hours before the test.
• Continue taking all regularly prescribed medications unless your doctor directs otherwise. Your doctor may ask you to taper off certain heart medications, such as digoxin or beta-blockers, a few days before the test.
• Remove all jewelry from your neck, arms, and wrists.
• Wear flat, comfortable shoes (no bedroom slippers) and loose, lightweight shorts or pants.
• Men and women should wear a loose fitting T shirt, women should wear a bra. Avoid wearing any restrictive clothing other than a bra.

What to Expect

The test is typically performed in the office in the stress laboratory. A technician will clean 10 small places on your chest and place a small electrode in each of the areas. Men may expect to have their chest shaved in these areas to help the electrodes stick. The electrodes are attached to an electrocardiograph (ECG) monitor, which allows the technician to monitor your heart's electrical activity during the stress test.

The physician will perform a baseline ECG and check your resting heart rate and blood pressure. The treadmill will start off slowly and will increase in speed and incline every 3 minutes.

At regular intervals, the lab personnel will ask you how you feel. Please inform them if you experience the following: chest pain, jaw pain, arm pain, shortness of breath, dizziness, or if you become lightheaded. It is normal for your heart rate, blood pressure and breathing rate to increase during the test. The lab personnel will monitor you for any symptom or changes on the ECG that suggest the test should be stopped. Your blood pressure and ECG will be recorded at various intervals during the test.

The test continues until you need to stop, until you reach your maximum heart rate, until you begin to show symptoms of significant stress on your heart and lungs (such as fatigue, extreme shortness of breath, or angina), or until the EKG shows evidence of decreased blood flow to the heart muscle. The test may also be stopped if you develop serious irregular heart rhythms or if your blood pressure drops below your resting rate.

When the exercise phase is completed, you will be asked to sit or lie down and rest. Your EKG and blood pressure will be checked for about 5 to 10 minutes during this recovery period. The electrodes are then removed from your chest, and you may resume your normal activities. You should not take a hot bath for at least an hour, since hot water after vigorous exercise can make you feel dizzy and faint. The entire test usually takes about 30 minutes.

3. Myoview Stress Test

A diagnostic study that uses a small amount of radioactive material injected into the vein in order to image the heart using a special camera called a gamma camera. This test allows the physician to determine if there is adequate blood flow to the heart at rest, as compared with activity.

How To Prepare

• Do not eat or drink anything for 5 hours before the test.
• Do not drink or eat caffeine products (cola, mountain dew, chocolate products, coffee, or tea) for 24 hours before the test. Caffeine will interfere with the results of the test.
• Do not take over-the-counter medications that contain caffeine for 24 hours before the test. Ask your doctor what prescription medications should be taken on the day of your test.
• Do not discontinue your medications without first talking to your doctor.
  If you use an inhaler for breathing, bring it with you on the day of the test.
• If you are diabetic, ask your physician how to adjust your medications the day of the test. If you own a glucose monitor, bring it with you to check your blood sugar levels before and after the test. If your blood sugar levels are abnormal, tell the lab personnel immediately.
• Wear comfortable clothes and shoes suitable for walking. Women should wear a bra.

What to Expect

A physician will explain the test and start an IV in your arm or hand. The physician will then inject a small amount of Myoview into the IV.

Myoview is a radioactive isotope that allows the physician to assess the blood perfusion to your heart. After the injection, there is a 45-minute wait and then you will be asked to lie very still under a camera for 15 to 20 minutes. These images will allow the physician to assess the blood flow to each area of the heart muscle at rest.After the rest scan is completed, you will be asked to wait for a period of time in the lobby.

Next you will go to the stress area of the laboratory. A technician will clean 10 small places on your chest and place a small electrode in each of the areas. Men may expect to have their chest shaved in these areas to help the electrodes stick. The electrodes are attached to an electrocardiograph (ECG) monitor, which allows the technician to monitor your heart's electrical activity during the stress test.

The physician will perform a baseline ECG and check your resting heart rate and blood pressure. The treadmill will start off slowly and will increase in speed and incline every 3 minutes.

If you are unable to walk on the treadmill, your doctor may order you to have the stress test done with medication. Adenoscan or Dobutamine can be used in place of the treadmill and will provide your physician with the same information about the blood flow to your heart.

At regular intervals, the lab personnel will ask you how you feel. Please inform them if you experience the following: chest pain, jaw pain, arm pain, shortness of breath, dizziness, or if you become lightheaded. It is normal for your heart rate, blood pressure and breathing rate to increase during the test. The lab personnel will monitor you for any symptoms or changes on the ECG that suggest the test should be stopped. Your blood pressure and ECG will be recorded at various intervals during the test.

One minute before you stop exercising, the nuclear technologist will give you another injection of a radioactive tracer called Myoview (a different radioactive isotope). This will allow the physician to visualize the blood perfusion to your heart during exercise.

After your stress test, the lab personnel will monitor your blood pressure and ECG until they return to normal levels.

About 20 minutes after you have finished exercising, you will lie back under the camera for an additional 15 - 20 minutes.