Background: Distal embolization during coronary angioplasty may result in vessel occlusion, no reflow and myonecrosis. This study tested the authors' clinical experiences using a guidewire system designed to preserve distal flow during angioplasty.
Methods and results: The FilterWire EX trade mark (Boston Scientific, Natick, MA, USA) consists of a 0.014-inch guidewire on which an expandable loop structure is attached to a porous polyurethane membrane. The assembly is delivered across the target lesion, followed by deployment of the filter distal to the lesion. Procedural and angiographic outcome data were obtained from patients undergoing saphenous vein grafts (SVGs) (n = 16) or native coronary (n = 4) interventions. The mean age was 62 +/- 10 years. All four patients with native coronary lesions sustained acute myocardial infarction while 15/16 patients with degenerated SVGs presented with accelerated angina pectoris. The mean proximal reference diameter was 3.62 +/- 0.32 mm, percentage diameter stenosis was 72 +/- 13%, and lesion length was 16.3 +/- 5.7 mm. Angiographic visible thrombus was detected in 12/20 (60%) cases. Stents were used in 19/20 patients (95%) with average stent diameter/length equal to 3.81 +/- 0.42/23 +/- 7 mm. Overall procedural success was obtained in 93.3% as no-reflow and total CK elevation occurred in 1/16 treated patients (6.7%) despite distal embolic filtration. In-hospital and 30-day survival was 100% with no episodes of target vessel thrombosis and/or myocardial infarction.
Conclusions: The use of the FilterWire EX seems to be feasible and safe in suitable lesion subsets and in relatively large-sized vessels among patients who are at high risk for distal embolization.