Incidence of Filter Slow flow in Patient with Acute Coronary Syndrome Using Distal Protection Device

Abstract

Aim: Effectiveness of distal protection device in primary PCI has been controversial. Actually, in daily practice we sometimes experience filter slow-flow after stenting and sometimes not. So we assumed that those cases which filter slow flow occurred should be the subsets which would receive the benefits by using distal protection devices for avoiding no-flow/slow-flow in ACS circumstances. Method: The subjects consisted of 273 consecutive ACS patients who underwent primary PCI using distal protection device (Filtrap, NIPRO) between May 2009 and January 2018. They were divided into 2 groups depending on the occurrence of filter slow-flow after stenting; the filter slow-flow (FS) group (n=129) and no filter slow-flow (nFS) group (n=144). Patient’s characteristics, lesion and procedural characteristics were analyzed between the two groups. Results: There were no significant differences in patient characteristics regarding cardiovascular risk factors (Hypertension, Diabetes, Hemodialysis and Smoking), except dyslipidemia (65.9% vs 42.3%, p < 0.01). The total occlusion lesion on control CAG was significantly common in FS group than nFS group (69.8% vs 57.6%, p <0.05). Moreover, the large amount of thrombus burden just after wiring were more likely found in FS group than nFS group (44.1% vs 2.1%, p < 0.01). The existence of calcification and tortuosity of lesion were fewer in FS group than nFS group (67.4% vs 85.3%, p < 0.01), which showed the lesions in FS group have more fragile atherosclerosis or thrombus. As a result, aspiration thrombectomy just after wiring (64.3% vs 27.1%, p <0.01) and predilatation procedures (61.2% vs 21.3%, p <0.01) were higher in FS group. Conclusion: These results demonstrate that the selective use of distal protection device in the fragile and high thrombus burden lesion which are more likely found in FS group is the key to avoid slow flow/no reflow phenomenon and serious adverse cardiac events after revascularization.