However, evidence exists that persistent ische- mia on testing is a prognostically poor finding. Exploratory data from a small cohort of 314 patients with SIHD enrolled in the COURAGE trial nuclear substudy revealed that a reduction in the ischemic myocardium is associated with an (unadjusted) reduction in the incidence of death or MI combined.306 In the BARI 2D trial, at 1 year of follow-up, more extensive and severe stress myocardial perfusion SPECT abnormalities were associated with higher rates of death or MI.276 There are, however, several circumstances in which a decision to perform follow-up testing is thought to be warranted in the absence of a change in clinical status, although data supporting this approach are limited. These circumstances include, but are not limited to, evaluation of incomplete revascularization, assessment of the adequacy of medical therapy by provocative exercise testing, a substantial change in risk profile, or the need to reevaluate coronary status in anticipation of major noncardiovascular surgery when the patient s exercise capacity is limited or unknown (although revascularization in this circumstance has not been shown to reduce the risk of perioperative cardiovascular complications), as detailed in the ACCF/AHA Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery Guideline.1250 Care should be taken when interpreting paired testing results to incorporate not only the change in the extent and severity of ischemia but also the workload at onset and total exercise capacity achieved, as these factors relate to the patient s symptom burden and functional correlates in daily life. Outside of such special circumstances, routine periodic testing is not recommended in patients who are at low risk for progression or had overt symptoms on initial presentation (ie, those without known silent ischemia) or very early after revascularization. 