Rheolytic thrombectomy with percutaneous coronary intervention for infarct size reduction in acute myocardial infarction: 30-day results from a multicenter randomized study.

OBJECTIVES: The goal of this work was to determine whether rheolytic thrombectomy (RT) as an adjunct to primary percutaneous coronary intervention (PCI) reduces infarction size and improves myocardial perfusion during treatment of ST-segment elevation myocardial infarction (STEMI).

BACKGROUND: Primary PCI for STEMI achieves brisk epicardial flow in most patients, but myocardial perfusion often remains suboptimal. Distal embolization of thrombus during treatment may be a contributing factor.

METHODS: This prospective, multicenter trial enrolled 480 patients presenting within 12 h of symptom onset and randomized to treatment with RT as an adjunct to PCI (n = 240) or to PCI alone (n = 240). Visible thrombus was not required. The primary end point was infarct size measured by sestamibi imaging at 14 to 28 days. Secondary end points included final Thrombolysis In Myocardial Infarction (TIMI) flow grade, tissue myocardial perfusion (TMP) blush, ST-segment resolution, and major adverse cardiac events (MACE), defined as the occurrence of death, new Q-wave myocardial infarction, emergent coronary artery bypass grafting, target lesion revascularization, stroke, or stent thrombosis at 30 days.

RESULTS: Final infarct size was higher in the adjunct RT group compared with PCI alone (9.8 +/- 10.9% vs. 12.5 +/- 12.13%; p = 0.03). Final TIMI flow grade 3 was lower in the adjunct RT group (91.8% vs. 97.0% in the PCI alone group; p < 0.02), although fewer patients had baseline TIMI flow grade 3 in the adjunct RT group (44% vs. 63% in the PCI alone group; p < 0.05). There were no significant differences in TMP blush scores or ST-segment resolution. Thirty-day MACE was higher in the adjunct RT group (6.7% vs. 1.7% in the PCI alone group; p = 0.01), a difference primarily driven by very low mortality rate in patients treated with PCI alone (0.8% vs. 4.6% in patients treated with adjunct RT; p = 0.02).

CONCLUSIONS: Despite effective thrombus removal, RT with primary PCI did not reduce infarct size or improve TIMI flow grade, TMP blush, ST-segment resolution, or 30-day MACE.