Answer
Exercise treadmill stress test
-Treadmill protocol (most common: Bruce) - speed & incline gradually increases every few min
- 65% accurate for severely narrowed arteries (so not very good)
-Assess for symptoms, and changes in blood pressure and ECG
Nuclear testing
-IV radioactive tracers (don't want to do too many in esp young women)
-Taken up by myocardium proportional to blood flow
-Emits radiation which can be measured
-85% accuracy (more accurate, more expensive)
-if change at rest vs stress, reversible defect = ischemia
-if no change at rest/stress, fixed defect = prior infarct
ECHO (u/s) testing
-Normal heart muscle thickens 50% when it contracts
-Abnormal heart thickening referred to as “wall motion abnormality”
-Wall motion abnormalities during stress but not at rest suggest ischemia
-90% accuracy, also expensive