What is a Stress Test?Posted on: 02.18.16 by Digirad
Myocardial Perfusion Imaging, also called Nuclear Stress Testing, is used to assess coronary artery disease, or CAD. CAD is the narrowing of arteries to the heart by the buildup of fatty materials. This condition may prevent the heart muscle from receiving adequate blood supply during stress or periods of exercise. It frequently results in chest pain, which is called angina pectoris.
A stress test provides detailed information about how efficiently your heart performs during physical stress. The test consists of injecting a small dose of radioactive material into the patient’s bloodstream, via an IV, and then imaging the heart commonly under two scenarios: the resting phase and the stress phase. Aptly named, the rest phase is the time at which the heart is at rest, prior to any exercise. The stress phase is the period of time after exercise when the heart is working hard and beating fast.
A stress test typically involves pedaling a stationary bike or walking on a treadmill at increasing levels of difficulty while your blood pressure and heart rate are being monitored. Images of your heart are taken with a nuclear camera prior to, and after, exercise. The comparison of the images can help identify any abnormalities and support a diagnosis.
Why do a stress test?
There are many reasons that your physician might order a stress test:
- To monitor the blood flow to your heart during increasing levels of activity
- To evaluate the effectiveness of any prescribed heart medication
- To determine the likelihood of having coronary heart disease
- To assess the effectiveness of a prior heart procedure
- To identify an abnormal heart rhythm
- To measure the reduced function of heart valves
A nuclear stress test is safe and highly effective in detecting irregularities. When the test is complete, patients may return to normal activities unless otherwise instructed. If the stress test identifies an issue or a concern, the doctor and patient will discuss an appropriate treatment plan.