In the latter instance, stress imaging to localize ischemia would be appropriate.580,581 Exercise test- ing early after STEMI may also be performed to 1) assess functional capacity and the ability to perform tasks at home and at work, 2) evaluate the efficacy of medical therapy, and 3) assess the risk of a subsequent cardiac event. Symptom- limited exercise testing is a key feature of the intake evalua- tion for enrollment in a program of cardiac rehabilitation 2 weeks after discharge.582 Low-level exercise testing after MI appears to be safe if patients have undergone in-hospital cardiac rehabilitation, including low-level exercise; have had no symptoms of angina or HF; and have a stable baseline ECG 48 to 72 hours before Two different protocols have been used for early post-MI exercise testing: the traditional submaximal exercise test (done at 3 to 5 days in patients without complications) or a symptom-limited exercise test (done at 5 days or later) with- out stopping at a prespecified target heart rate or metabolic equivalent level. RCTs of early exercise testing after PCI have excluded patients with recent MI.584 Limited data exist on the safety of early symptom-limited exercise testing after MI; therefore, clinical judgment must be used.585 Pharmacological stress myocardial perfusion imaging has been shown to have predictive value for postinfarction cardiac events and is useful and safe in patients who are unable to exercise.586 The opti- mum timing for provocative testing for ischemia after STEMI remains unresolved. 