Introduction: There is lack of information about intracoronary (ic) fibrinolysis in the era of primary PCI. Our purpose was to compare the effects of ic administration of a fibrinolytic drug (tenecteplase -TNK-) to that of a GP IIb/IIIa inhibitor (abciximab -ABC-) on myocardial perfusion and infarct size in pts with acute STEMI of anterior location undergoing primary PCI.
Methods: We randomly assigned 76 pts to receive ic TNK (one-fifth part of usual systemic dose) or ABC (0.25 mg/kg ic plus iv infusion for 12 h) during primary PCI. All pts also received heparin, aspirin and clopidogrel as usual. Pts were recatheterized on the second day after primary PCI in order to obtain parameters of epicardial flow (corrected TIMI frame count -cTFC-) and myocardial perfusion (TIMI myocardial perfusion grade -TMPG-, grades 0-3), which were evaluated at an external core-lab. MACE included cardiac death, re-infarction, stroke and urgent TLR. Pts were also scheduled for cardiac-MRI (at 4 months) and echocardiography (at 6 months) for a blinded assessment of infarct size (the primary end-point of study) and LV function.
Results: Compared to ic-ABC group, pts in ic-TNK group showed worse parameters of epicardial flow and myocardial perfusion at 48-h catheterization. Of note, 2/38 pts (5.3%) in ic-TNK group experienced subacute stent thrombosis. At 4 months, infarct size was not significantly different in ic-TNK group to that in ic-ABC group. LV volumes and LVEF did not significantly differ between study groups, but diastolic function (as assessed by E/e′ratio) was better preserved in ic-TNK group.
Conclusions: In our pilot trial, ic fibrinolysis with TNK during primary PCI in anterior STEMI pts did not seem to provide meaningful benefit as compared to that of ic ABC in terms of reduction of infarct size, and it showed worse myocardial reperfusion during the acute phase. In addition, subacute stent thrombosis could be a matter of concern in relation to ic fibrinolysis.