Stress tests are screening tools to help detect heart disease.
EKG monitoring is performed while you walk on a treadmill. The speed
and incline of the treadmill increase every three minutes until you
reach a maximum heart rate, become fatigued, develop symptoms, or have
specific EKG changes.
Nuclear stress tests, commonly performed as dual isotope stress
tests or thallium stress tests, use radioactive tracers including
Thallium-201 and Myoview to image the heart at rest and following
treadmill exercise. You lie flat under an imaging camera for roughly
15 minutes before and after the treadmill test. Nuclear stress tests
increase the sensitivity of routine treadmill testing, and allow
specific assessment of different areas of the heart muscle.
If you are unable to walk on the treadmill or have specific conduction
defects on your EKG, an Adenosine stress test
may be ordered. Intravenous Adenosine
dilates the heart arteries
and mimics the effect of walking on the treadmill. Adenosine
is
followed by nuclear imaging. Adenosine
is not suitable for
asthmatics.
The Dobutamine dual isotope stress test substitutes intravenous
dobutamine for adenosine. Dobutamine stresses the heart by
increasing the heart rate and its contractility. Nuclear imaging is
performed before and after Dobutamine infusion.
Patient Preparation:
- No food or drink four (4) hours before the test.
- No caffeine 24 hours before the test.
- Take your medications with sips of water unless otherwise
instructed.
- Wear loose, comfortable clothing and shoes suitable for walking.
- Bring a list of current medications.
- Plan on spending one (1) hour for a regular stress test and four
(4) hours for a nuclear stress test.
