Overview of exercise stress testing

Exercise stress testing is a non-invasive, safe and affordable screening test for coronary artery disease (CAD), provided there is careful patient selection for better predictive value. Patients at moderate risk for CAD are best served with this kind of screening, with the exception of females during their reproductive period, when a high incidence of false positive results has been reported. Patients with a high pretest probability for CAD should undergo stress testing combined with cardiac imaging or cardiac catheterization directly. Data from the test, other than ECG changes, should be taken into consideration when interpreting the exercise stress test since it has a strong prognostic value, i.e. workload, heart rate rise and recovery and blood pressure changes. Only a low-level exercise stress test can be performed early post myocardial infarction (first week), and a full exercise test should be delayed 4 to 6 weeks post uncomplicated myocardial infarction. The ECG interpretation with myocardial perfusion imaging follows the same criteria, but the sensitivity is much lower and the specificity is high enough to overrule the imaging part. Exercise stress testing has been used for decades as a noninvasive test to diagnose and risk stratify coronary artery disease (CAD). However, it lacks adequate sensitivity, which nevetheless depends on the pretest probability of CAD in the population tested. The overall sensitivity has ranged from 60% to 70% with a specificity of 85%.1,2,3 Due to the innumerable criteria set for the EKG stress test interpretation and reporting, a lot of confusion arises between institutions. To make it easier on the practitioner at our institution, we have adopted the criteria outlined in this review for interpretation of test results.