['ST-segment resolution (STR) is a well-established and simple tool for assessing the efficacy of reperfusion therapy in myocardial infarction. An incomplete (<50%) STR is a recognized marker of failed thrombolysis and a suitable recruitment criterion for rescue angioplasty.', 'We sought to determine the predictive value of the total absence of STR after thrombolysis in rescue angioplasty (percutaneous coronary intervention [PCI]).', 'Eighty-one consecutive patients who underwent a rescue angioplasty for failed thrombolysis in our institution from 2001 to 2007 were included. Two groups of patients were defined according to their STR extent, 90 minutes after lysis: partial resolution group 1 (10%-50% STR) vs absence of resolution group 2 (<10% STR) and compared in terms of in-hospital and long-term outcomes.', 'Patients of group 2 were more likely to experience hemodynamic deterioration (50% vs 24%; odds ratio [OR] = 3.17; P = .017), to have a Thrombolysis in Myocardial Infarction 0 flow on the culprit artery (62.3% vs 42%; OR = 2.24; P = .045), to have a multivessel disease (66.7% vs 40%; OR = 3; P = .018), and to die during index hospitalization (26.7% vs 6%; OR = 5.69; P = .013) despite statistically similar rates of PCI failure in both groups (10% vs 7%; P = .402) and similar post-PCI STR (72% +/- 18.25% vs 75% +/- 11.62%; P = .36). In multivariate analysis, total absence of STR proved to be an independent predictor of in-hospital mortality (HR = 7.02; P = .032; 95% confidence interval, 1.18-41.58). Long-term major adverse cardiac events occurred more frequently in group 2 (log rank, P = .004) and were (on the Cox regression model) independently predicted by total absence of STR (HR = 6.21; P = .023; 95% confidence interval, 1.28-29.1).'] Is total absence of ST-segment resolution after failed thrombolysis correlated with unfavorable short- and long-term outcomes despite successful rescue angioplasty?