Limitations of Embolic Protection in Saphenous Vein Graft Intervention: Insights from 202 Consecutive Patients

Abstract

Between January 2003 and September 2006, a total of 2,541 patients had percutaneous coronary intervention (PCI). Of these, 202 (226 grafts) had at least one saphenous vein graft (SVG) intervention. Adjunctive distal embolic protection (DEP) devices were attempted in 123 SVGs (54.4%). The 30-day major adverse cardiac event (occurrence of death, myocardial infarction, or target vessel revascularization) rate in the overall group was 11.9%. The presence of angiographic thrombus independently predicted DEP use while the presence of in-stent restenosis predicted no DEP use. Although the presence of all angiographic technical feasibility criteria independently predicted DEP use, only 72 (32.4%) and 33 (14.6%) of the SVGs would have been eligible for the occlusive balloon- and filter-based distal embolic criteria, respectively. The most common technical reason for ineligibility was a graft size smaller than 3.0 mm, followed by the lack of a long enough landing zone. In a subset of 21 (9.3%) completely occluded lesions which would have excluded DEP use, angiographic success was 66.7%, and that was predicated on successful debulking with rheolytic thrombectomy in 13 (61.9%) with subsequent DEP in 5 (23.8%). In conclusion, not all grafts can be protected, and even in those that can, such protection may be incomplete. Newer embolic protection devices, such as the Proxis((R)), were recently introduced to expand the applicability to a wider population of vein grafts. However, further design improvements such as device miniaturizations applicable to sub-3.0-mm vessels and better particle removing/filtering mechanisms are needed in order to expand the use of embolic protection to reduce the persistently high complication rates associated with this difficult- to-treat subset of patients.