OBJECTIVETo investigate whether thrombus aspiration plus intra-infarct-related artery bolus administration of tirofiban via the aspiration catheter is superior to thrombus aspiration alone in improving myocardial perfusion in patients with ST-elevation myocardial infarction (STEMI) undergoing primary angioplasty.

METHODSIn this single center retrospective study, 108 patients with STEMI who underwent angioplasty after thrombus aspiration plus intra-infarction related artery 500 µg tirofiban administration, with subsequent 12-hour intravenous infusion of 0.1 µg×kg(-1)×min(-1) after angioplasty (thrombus aspiration + tirofiban group) and 108 matched control patients with STEMI who underwent angioplasty after thrombus aspiration (thrombus aspiration group). The primary end points included thrombolysis in myocardial infarction (TIMI) flow immediately after angioplasty, complete ST-segment elevation resolution (> 70%) at 90 minutes after angioplasty and the peak of creatine kinase-MB (CK-MB) and troponin I (TnI). The secondary end points were the left ventricular ejection fraction (LVEF) in the hospital and at 9 months follow-up as well as major adverse cardiac events (MACE: cardiac death, target vessel revascularization, re-infarction) at 9 months and any bleeding events.

RESULTSBaseline characteristics of the two groups were well-balanced. The TIMI 3 flow rate (97.22% vs. 87.04%, P = 0.011) and the complete ST-segment resolution rate (66.67% vs. 50.91%, χ(2) = 6.129, P = 0.047)were significantly higher in the thrombus aspiration + tirofiban group than in the thrombus aspiration group. The peak of CK-MB (83.9 U/L vs. 126.1 U/L, P = 0.034) and TnI (42.7 ng/ml vs. 72.5 ng/ml, P = 0.029) were significantly lower in the thrombus aspiration + tirofiban group than in the thrombus aspiration group. LVEF in the hospital favored thrombus aspiration + tirofiban the group (45.7% ± 10.8%, 42.9% ± 9.9%, t = 1.99, P = 0.049). There was a tendency to decreased MACE rate at 9-month follow-up, which favored thrombus aspiration + tirofiban the group (logrank χ(2) = 2.865, P = 0.09). Bleeding events were similar between the two groups.

CONCLUSIONThrombus aspiration plus intra-infarct-related artery bolus administration of tirofiban in patients with STEMI undergoing primary angioplasty may improve myocardium perfusion, attenuate myocardial ischemia and result in a better clinical prognosis compared to thrombus aspiration alone.