Safety and Efficacy of the FilterWire EZ in Acute ST-Segment Elevation Myocardial Infarction

Abstract

Primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI) achieves a high epicardial reperfusion rate; however, it is often suboptimal in achieving myocardial reperfusion due to distal embolization of atherothrombotic particles. The present study assessed whether the capture of embolic particles during PCI would improve myocardial reperfusion outcome. In a multicenter, prospective, randomized, controlled study, 100 patients with STEMI and coronary angiographic evidence of thrombotic occlusion were randomly assigned to PCI using the FilterWire EZ (n=51) or a control group (n=49) using regular guidewires. The FilterWire EZ was successfully delivered across the lesion in 84% of patients in the FilterWire EZ group. Primary efficacy end points, including markers of epicardial (Thrombolysis In Myocardial Infarction grade flow) and myocardial reperfusion (myocardial blush score and percent early resolution of ST-segment elevation), did not differ between the 2 study groups. Further, 60- and 90-minute percent ST-segment resolutions were identical in the 2 groups. In a subgroup analysis, a blush score of 3 was achieved in 94% of patients in whom the filter's landing zone was in a vessel diameter>2.5 mm compared with only 55% in those with smaller vessel diameter (p=0.04). This corresponds to a better debris capture in filters located in large versus small vessels (p=0.08). In conclusion, in patients with STEMI, use of the FilterWire EZ as an adjunct to primary PCI did not improve angiographic or electrocardiographic measurements of reperfusion compared with conventional PCI only.