ST-Segment resolution as a marker of epicardial and myocardial reperfusion after thrombolysis: insights from the TIMI 14 and in TIME-II trials.

Patients with persistent ST segment elevation after fibrinolysis are at high risk for death and congestive heart failure, even if normal epicardial flow has been restored. In the TIMI 14 trial, combination therapy with abciximab plus reduced-dose alteplase enhanced the speed and efficacy of epicardial reperfusion. We also found that combination therapy provided an additional benefit in terms of myocardial reperfusion, as evidenced by greater ST resolution on serial 12-lead electrocardiograms. Specifically, the proportion of patients with complete (> or =70%) ST resolution was higher among patients receiving combination therapy than in those treated with alteplase alone (59% vs 37%; p < 0.0001). Even among patients with normal (TIMI grade 3) epicardial blood flow, combination therapy was associated with a significantly greater likelihood of complete ST resolution than was fibrinolysis alone (69% vs 44%; p = 0.0002). In conclusion, combination reperfusion therapy improved myocardial (microvascular) reperfusion, independent of epicardial flow, suggesting an additional mechanism by which abciximab may improve outcomes in patients with acute MI.