Relation of impaired Thrombolysis In Myocardial Infarction myocardial perfusion grades to residual thrombus following the restoration of epicardial patency in ST-elevation myocardial infarction

Clinical and angiographic data were analyzed from 929 patients who had ST-elevation myocardial infarction and open epicardial arteries after fibrinolytic therapy. Residual angiographically evident thrombus was associated with more frequent Thrombolysis In Myocardial Infarction (TIMI) grade 2 flow (33.6% vs 26.8%, p = 0.03), higher corrected TIMI frame counts (34 vs 31 frames, p = 0.0003), and lower TIMI myocardial perfusion grades (43.0% vs 32.0% TIMI myocardial perfusion grades 0/1, p = 0.001) among all patients and among patients who had TIMI grade 3 flow (33.5% vs 26.0% TIMI myocardial perfusion grades 0/1, p = 0.043). In multivariate analyses, angiographically evident thrombus was associated with higher corrected TIMI frame counts and worsened myocardial perfusion independent of clinical and angiographic covariates, including TIMI grade 3 flow.