The clinical implications of isolated late recovery ST depression were tested in patients with scintigraphically defined ischemia (coronary artery disease [CAD], n = 18) compared with patients without ischemia (n = 25). Spontaneous (78.4 versus 12.0%, P < 0.008) and exercise-induced angina (44.4 versus 0%, P < 0.0001) were more frequently seen in patients with CAD. Histories of unstable angina (33.3%), prior myocardial infarction (27.8%), ST elevated angina (22.2%) and significant stenosis in the left anterior descending artery (17 of 18, 94.4%) were almost exclusively seen in the CAD group. There was no significant difference between the two groups in capacity for exercise, maximum deviation of ST level or TV2 amplitude. Balloon angioplasty abolished late recovery ST changes in 63.6% of CAD patients. These results suggest that isolated late recovery ST depression, when accompanied with typical chest pain, may be considered as an indicator of myocardial ischemia, but this phenomenon is difficult to distinguish electrocardiographically.