ANGIOGRAPHIC PREDICTORS OF REOCCLUSION AFTER THROMBOLYSIS - RESULTS FROM THE THROMBOLYSIS IN MYOCARDIAL-INFARCTION (TIMI)-4 TRIAL

Objectives. This study attempted to determine which lesion characteris tics are associated with reocclusion by 18 to 36 h. Background. Reoccl usion of the infarct-related artery after successful reperfusion is as sociated with significant morbidity and up to a threefold increase in mortality. Methods. Two hundred seventy-eight patients with acute myoc ardial infarction were randomized to receive either anisoylated plasmi nogen streptokinase activator complex (APSAC) or recombinant tissue-ty pe plasminogen activator (rt-PA) or their combination. Culprit arterie s were assessed for Thrombolysis in Myo cardial Infarction (TIMI) flow grade, lesion ulceration, thrombus, collateral circulation and eccent ricity. Minimal lumen diameter, percent diameter stenosis and lesion i rregularity (power) were calculated using quantitative angiography.Res ults. Reocclusion was observed more frequently in arteries with TIMI 2 versus TIMI 3 how (10.4% vs. 2.2%, p = 0.003), in ulcerated lesions ( 10.7% vs. 3.0%, p = 0.009) and in the presence of collateral vessels ( 18.2% vs. 5.6%, p = 0.03). Similar trends were observed for eccentric (7.3% vs. 2.3%, p = 0.06) and thrombotic (8.4% vs. 3.3%, p = 0.06) les ions. Reocclusion was associated with more severe mean percent stenosi s (77.9% vs. 73.9%, p = 0.04). Lesion length, reference segment diamet er and Fourier measures of lesion irregularity were not associated wit h reocclusion. Conclusions. Several simply assessed angiographic varia bles, such as the presence of TIMI grade 2 flow, ulceration, collatera l vessels and greater percent diameter stenosis at 90 min after thromb olytic therapy, are associated with significantly higher rates of infa rct-related artery reocclusion by 18 to 36 h and may aid in identifyin g the subset of patients who are at significantly higher risk of early reocclusion and who potentially warrant further early pharmacologic o r mechanical intervention.