Often a cardiac stress test is indicated prior to any surgically procedure to assess your heart function and determine operative risk. There are numerous ways for this to be performed. If you are able, you may be asked to run on a treadmill to elevate your heart rate. If you are not able to exercise, then a medication can be injected through an IV line (intra-venous; into a vein) to mimic exercise.
For instance, dobutamine (Dobutrex) can be used to elevate your heart rate. This medication is also the preferred drug for patients with chronic obstructive pulmonary disease (COPD), asthma, or an active wheeze. Other options are adenosine (Adenoscan) or dipyridamole (Persantine) which act as vasodilators, that is, they make your blood vessels open wider and thus increase blood flow.
If you take theophylline (Bronkodyl; Elixophyllin; Slo-bid; Slo-Phyllin; Theo-24; Theo-Dur; Theolair; Uniphyl), you cannot take it 24 hours prior to the test. This test is not recommended for patients who actively wheeze.
Exercise treadmills and dobutamine stress tests depend on your heart rate. If you take medication such as a beta blocker, you may be asked to not take it for a few dosages. Often a nuclear stress test is ordered, in which images of your heart are taken at rest and during stress. These images give an indication of whether there are areas of poor blood flow to the heart muscle (perfusion ) and overall heart function.
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