CARDIAC STRESS TESTS
Heart disease is the leading cause of death in the United States with coronary artery disease, or CAD, being the most common type. If you have symptoms of this disease, or are at risk for developing it, your healthcare provider may order a coronary stress test.
Risk factors for coronary artery disease include increased age, family history of heart disease, smoking, diabetes, high cholesterol, high blood pressure, obesity, poor diet and decreased physical activity. The more risk factors you have, the greater chance you have of developing heart disease.
A cardiac stress test evaluates how well your heart is working by determining how well blood flows through the coronary arteries when your heart is “stressed.” It is easier to see the effects of heart disease when your heart is “stressed,” which means when your heart beats faster and works harder. During a stress test, the staff monitors your heart at rest and during “stress” and, if necessary, performs other heart tests. In some cases, pictures are taken of your heart and arteries before and after increasing your heart rate.
Reasons for Having Cardiac Stress Tests
- Your healthcare provider may order a cardiac stress test:
- When you have known or suspected coronary artery disease.
- To help predict how much stress your heart can manage before developing an abnormal rhythm or ischemia (when not enough blood is flowing through the coronary arteries to the heart muscle).
- To evaluate the effectiveness of your heart medications and/or procedures performed on your heart.
- To help work out a safe exercise program.
Types of Cardiac Stress Tests
There are several ways to do a stress test. The exercise stress test is the most commonly performed stress test. It is also called a stress test, exercise electrocardiogram, treadmill test, graded exercise test or stress ECG. If you are able to exercise, you will walk on a treadmill or pedal a stationary bicycle.
If you are unable to exercise, a pharmacologic or drug stress test may be done. A medication is injected into your bloodstream that will make your heart beat faster. With this way, the staff can still determine how your heart reacts to stress without exercising.
An echocardiogram is a graphic outline of the heart’s movement. During a stress echocardiogram, the movement of the heart’s walls and pumping action while it is stressed is seen on a monitor. It may reveal a lack of blood flow that is not visible with other tests.
A nuclear stress test helps determine which parts of the heart are healthy and which are not. A small and harmless amount of radioactive material is injected into your blood stream. A special camera monitors the substance in your body and takes pictures of your heart while you are at rest and after exercise.
Preparation for the Exercise Stress Tests
Most likely, you will be asked not to eat, drink or smoke for at least two to four hours before the test. Ask your healthcare provider whether you should take your prescribed medicines, including those for your heart, on the day of the test. If you take insulin to control your blood sugar, find out the amount you should take. You should not take Viagra, or its generic form, within 24 hours before the test. Be sure to wear clothes and shoes that are comfortable for exercise.
If you are having a drug stress test, stress echocardiogram or nuclear stress test, the preparations vary from those of the exercise stress test. Ask your healthcare provider for specific instructions.
What to Expect for the Exercise Stress Test
The technician does an EKG before you start to exercise. Electrodes (patches with wires) are placed on your chest, arms and legs. Your blood pressure, heart rate and breathing rate will also be measured. In some cases, the oxygen level in your blood may be tested. These measurements will be checked during and after the test.
When it is time to exercise, you will either use a treadmill or stationery bicycle. You may notice the treadmill tilt as if you are walking up hill. The treadmill speed will also change to make you walk faster. If asked to pedal a stationary bicycle, you may find it easy at first. As the resistance increases, it gradually gets harder to pedal.
Toward the end of the test, you will have a cool down period during which you will slow your activity and stand, sit or lie still. Your EKG and other vital signs will be recorded again and may be monitored for about 10 to 15 minutes until your heart beat returns to its original resting rate.
Benefits and Risks
Your healthcare provider uses cardiac stress tests to help diagnose coronary artery disease, evaluate the extent of the disease, decide how to treat the disease, assess your ability to exercise and rule out other possible causes of your symptoms. Exercise stress tests involve very little risk. On rare occasions, serious problems may occur during the test such as abnormal heart rhythms or heart attack. Qualified healthcare professionals are available during the test to handle any emergencies that may occur.
At this time, the advice for people without symptoms and with a low risk of heart disease is not to have an exercise stress test. However, there are certain groups that may benefit from exercise testing if they do not have heart symptoms. These groups include people with diabetes or multiple risks factors for heart disease who are starting a vigorous exercise program, selected people who work in public safety jobs such as airline pilots, or people that work in jobs that require a high level of heart function, such as firefighters.
You should not have a stress test if you have:
- Unstable chest pain.
- Uncontrolled heart failure or heart arrhythmia (abnormal heart rhythm).
- Acute blood clots.
- Had a heart attack in the past two days before the test.
- Check with your healthcare provider to find out if an exercise stress test is right for you.
What To Do
- Be sure the testing staff is aware of all the medicines you take.
- Inform the testing staff immediately if you have palpitations, chest pain or tightness, pain in your left shoulder, arm or jaw, shortness of breath, dizziness or any other discomfort during the test.
- You may stop the test if you feel you cannot exercise any further.
What We Have Learned
A cardiac stress test evaluates how well your heart is working when it is “stressed.”
True or False
The answer is true
Exercise stress tests involve very little risk for complications.
True or False
The answer is True
You should notify the staff immediately if you have chest pain or any other discomforts during the stress test.
True or False
The answer is True
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