Stress tests are used to measure the performance of your heart and/or lungs while under physical stress. Stress tests provide information on how your heart responds to exertion.
Metabolic Exercise Stress Test
The metabolic stress test is used to:
. Determine the health of your heart and lungs
. Diagnose symptoms of shortness of breath or chronic fatigue (medical problem or poor fitness)
. Measure your heart’s functional capacity
. Evaluate the effectiveness of your cardiac treatment program.
How Do II Prepare?
To prepare for the test, do not eat or drink anything for four hours prior to the test and do not drink or eat anything containing caffeine or use tobacco products for 24 hours prior to the test. Caffeine and nicotine can interfere with the results. Do not smoke on the day of the test.
Consult your doctor about the medications that should be taken on the day of your test. Please tell your doctor if you are currently taking Viagra and if you have had a dose in the past 24 hours. This drug cannot be given with nitroglycerine that may be used to treat potential chest pain during the procedure If you use an inhaler, bring it with you, and if you are diabetic, talk to your physician on how to adjust your medications the day of the test. Be sure to wear comfortable clothes and soft-soled shoes. Do not wear jewelry or bring valuables with you.
What Can I Expect?
Ten electrode patches will be attached to your chest and then to an electrocardiograph (ECG) monitor. This will chart your heart’s activity during the test. Men may have their chest partially shaved so the electrodes will stick. The technician will get a resting ECG, heart rate and blood pressure rate before you start exercising. You will be asked to breathe through a mouthpiece for a few minutes before you begin the test. You will then continue breathe only through your mouth throughout the test. A nose-clip will be placed on your nose.
You will begin walking on a treadmill or pedaling a stationary cycle. The degree of difficulty will gradually increase, and you will be asked to continue until you are exhausted. Your ECG, heart rate, blood pressure and breathing rate will be monitored throughout the test. An increase in these rates is normal during the test. The technician will ask how you are feeling at regular intervals. The questions will be phrased in a way that you will "nod" your answers, yes or no. Please tell them if you experience any chest, arm or jaw pain; dizziness; lightheadedness; or any other unusual symptoms.
After the test you will cool down by walking or pedaling slowly for a couple of minutes. The appointment usually lasts about one hour and 15 minutes, and the actual exercise is usually 15 minutes or less. In some cases, your appointment may take up to three hours.
Thallium Stress Test
This is a type of nuclear scanning test or myocardial perfusion imaging test. It shows how well blood flows to the heart muscle and is usually performed along with an exercise stress test.
The thallium stress test is used to determine:
, How much your coronary arteries are blocked
. Your health outlook after a heart attack
. How well cardiac procedures worked to improve circulation in the coronary arteries
. What’s causing your chest pain
. How much exercise is safe for you to do.
When you reach your maximum level of exercise, a technician will inject thallium, which is a radioactive substance, into your bloodstream. Then you lie down on a special table under a camera that detects the thallium and makes pictures of your heart. Thallium moves through your bloodstream and actually enters the cells of the heart muscle. The pictures taken during a thallium stress test can show areas of the heart that aren’t receiving enough blood because less thallium will show up in that area.
Pictures of the heart are made in a series starting shortly after the exercise portion of the test to show the heart under stress. You’ll then lie quietly for a few hours so that pictures can be made of the heart at rest. This will give your doctor a comparison of your heart working and resting.
Chemical Stress Test
If you have health problems that prevent you from exercising, your doctor may ask for a chemical stress test. This type of test uses special drugs such as dipyridamole or adenosine that increase blood flow to the heart so that your heart acts like you have been exercising.
Your ECG will be monitored throughout the test. Thallium will be injected into your bloodstream and two sets of images will be taken, one following administration of dipyridamole or adenosine and one following a period of rest. Each set of pictures takes between 15-30 minutes.
It is important to let the technician know if you experience any shortness of breath, headache, chest pains, palpitations or a flushed feeling during the test.