Objectives: It is unclear whether the completeness of revascularization impacts on the prognostic value of an exercise test after primary percutaneous coronary intervention (PCI). Methods: The DANAMI-2 trial included patients with ST elevation acute myocardial infarction randomized to primary PCI or fibrinolysis. Of the 790 patients randomized to primary PCI, 572 performed an exercise test. Prospectively, 310 patients were classified as having complete and 216 as having incomplete revascularization. Primary endpoint was a composite of reinfarction and/or death. Results: Patients with incomplete revascularization had lower exercise capacity [6.5 (95% CI: 1.9-12.8) vs. 7.0 (95% CI: 2.1-14.0) METs, p = 0.004] and more frequently ST depression [43 (20%) vs. 39 (13%), p = 0.02] compared to patients with complete revascularization. ST depression was not predictive of outcome in either groups, while multivariable analyses showed that exercise capacity was predictive of reinfarction and/or death in patients with incomplete revascularization [hazard ratio = 0.71 (95% CI: 0.54-0.93), p = 0.012] or of death alone [hazard ratio = 0.56 (95% CI: 0.41-0.77), p = 0.0003], which was not found in patients with complete revascularization. Conclusions: Exercise capacity was prognostic of reinfarction and/or death in patients with incomplete revascularization, but not in completely revascularized patients. ST segment depression alone did not predict residual coronary stenosis or dismal prognosis.