Under what circumstances would a patient need a stress test?
Patients may be scheduled for stress tests to evaluate symptoms of chest pain, for an exercise prescription, to evaluate for exercise induced arrhythmia or for surveillance of known coronary artery disease.
Do all stress tests require physical exercise?
Graded exercise tolerance tests (GXT), whether with or without imaging require exercise on a treadmill to achieve the patient’s target heart rate, which is determined by patient’s age. Pharmaceutical Nuclear stress tests do not require exercise.
When is a nuclear stress test needed versus an exercise stress test?
Pharmaceutical Nuclear stress tests are utilized when patients are unable to exercise, in cases of certain ECG (electrocardiogram) abnormality, when the patient is unable to reach the target heart rate with exercise due to medications, or when a patient has certain brady arrhythmias (slow heart rates requiring pacemaker). Nuclear stress tests, where treadmill exercise is used along with nuclear images, are generally ordered versus a standard GXT when the baseline ECG is abnormal, when imaging is desired because of the patient’s coronary anatomy or a previous standard GXT was not quite normal.
GXT or Stress Nuclear test requires walking on the treadmill long enough to raise the heart rate to target as well as long enough to be physically stressed (tired, short of breath, etc.). The treadmill gradually speeds up and elevates incline every three minutes. Most patients exercise for 7-9 minutes, depending on functional capacity. Be sure to dress comfortably with appropriate shoes for exercise.
With a nuclear or medication-induced stress test, what should I expect?
With a pharmaceutical nuclear study, the patient does not exercise. Lexiscan Nuclear dilates the patient’s arteries as if they have exercised. They may experience shortness of breath with the medication. Also, patients are encouraged to eat 2 hours prior to the test to reduce any GI effects. Patients must avoid all caffeine products for 24 hours prior to Nuclear stress tests.
How long does the test take?
Patients are usually here for about 30 minutes for a GXT secondary to paperwork, setup and recovery. We ask patients to anticipate being here for 2 hours for a Nuclear stress test to allow for imaging. There is a second day of testing required for Nuclear stress tests, however patients are usually only here for approximately one hour for injection and imaging.
What can be revealed about your heart health during these types of tests?
All stress tests are screening tests and cannot exclude the presence of Coronary Artery Disease (CAD) or progression of CAD, but exercise stress tests give a good idea of functional capacity and prognosis if the patient does have CAD. Also, nuclear imaging gives a good idea of coronary perfusion which helps the cardiologist determine if further testing is needed.
If I “fail” my test, what’s the next step?
If a GXT is abnormal, your provider may recommend a Nuclear stress test or a cardiac catheterization. Every situation is different and other health history comes into play for this decision. Nuclear stress tests that are abnormal may indicate older heart damage or narrowing / blockages in the arteries. Therefore the provider would recommend catheterization vs. medical management based on the particular situation. Next steps are usually discussed at a follow up appointment after all testing is completed.