| A cardiac stress test evaluates heart function during exertion. During exertion, the heart's demand for oxygen is increased. Testing the heart's reaction to this increased demand provides information necessary for the diagnosis of cardiac disease or abnormalities.
The heart's reaction to the exertion is usually measured by electrocardiography (ECG). ECG is a test that uses 12 sensors placed at specific locations on the individual's body. Through these sensors, the heart's electrical activity is measured. Additional methods of measuring the heart's reaction during a stress test include echocardiography, which uses ultrasound to visualize the heart structures, and myocardial perfusion scanning, an imaging procedure that uses a radioactive compound.
The cardiac stress test is widely used for evaluation in individuals with suspected or proven cardiac disease. Coronary artery disease (CAD) is a major cause of disease and death. The treadmill cardiac stress test has a sensitivity and specificity for CAD of 65% to 80% (Tate 119). |
Source: Medical Disability Advisor
| A cardiac stress test is performed to screen for coronary artery disease (CAD) in symptomatic individuals, to evaluate chest pain and its cause, to diagnose or rule out coronary artery disease, to identify arrhythmias that develop during exercise, to determine the functioning capacity of the heart after surgery or myocardial infarction, and to evaluate the effectiveness of therapy for cardiac arrhythmias or ischemic disorders.
This test may be used as part of an initial evaluation for CAD instead of coronary angiography, particularly if the suspicion for atherosclerotic heart disease is lower. In an individual thought to be at high-risk for atherosclerosis, this test may be skipped and a coronary angiogram performed as part of the initial evaluation. |
Source: Medical Disability Advisor
| The individual undergoing cardiac stress testing abstains from eating, drinking, or smoking 2 to 4 hours before testing. A resting (baseline) ECG is obtained before beginning the test.
Exertion is typically induced by exercise, such as pedaling a stationary bicycle or walking on a treadmill. After an initial warm-up phase on the selected mode of exercise, the workload is gradually increased by small increments. At each exercise level (or after each minute of exercise, depending on the protocol), an ECG is recorded. ECGs are also recorded periodically for at least 6 to 10 minutes after exercise is stopped. If insufficient blood supply to the heart muscle (myocardial ischemia) develops during exercise, characteristic ECG changes will appear. Blood pressure is also checked at frequent intervals, and the individual is asked to report any symptoms. In individuals who cannot perform the exercises, the cardiac effects of exercise may be simulated with certain medications that dilate the blood vessels (adrenergic or coronary vasodilators).
If echocardiography is done in conjunction with the stress test, a baseline echocardiogram is obtained prior to exercise. Another is done immediately after exercise. From these images, motion of the heart wall can be analyzed. If myocardial ischemia develops during exercise, abnormal wall motion will appear in the area of ischemia. If myocardial perfusion scan is performed, a radioactive compound is injected into a vein. The compound circulates throughout the heart and is taken up by the heart muscle (myocardium). The radioactivity is detected by special cameras that produce an image of the heart, revealing areas of oxygen deficiency (ischemia). The scan is obtained immediately after stopping exercise, and a second scan is done several hours later after resting. When an individual is unable to exercise, medications that simulate the cardiac effects of exercise may be given instead. |
Source: Medical Disability Advisor
| The cardiac stress test is an effective and widely used procedure that provides information about an individual's heart and how it responds to exertion. This information is invaluable in screening for and evaluating heart disease. |
Source: Medical Disability Advisor
| The test may need to be stopped if irregular heart action (arrhythmias), a drop in blood pressure below baseline, chest pain (angina), difficulty breathing (dyspnea), dizziness or fainting, uncontrolled hypertension, excessive fatigue, or other significant symptoms occur. The possibility of fatal cardiac arrhythmias or myocardial infarction exists. Testing is terminated when maximum capacity (target heart rate) is reached or the individual asks to stop. |
Source: Medical Disability Advisor
| There are no restrictions or accommodations associated with a cardiac stress test. |
Source: Medical Disability Advisor
| Tate, C. "Cardiovascular diseases." Practical Guide to the Care of the Medical Patient. 6th ed. St. Louis: Mosby-Year Book, Inc., 2004. 119-121. |
Source: Medical Disability Advisor