Platelet glycoprotein IIb/IIIa receptor inhibition as adjunctive treatment during saphenous vein graft stenting: differential effects after randomization to occlusion or filter-based embolic protection

Abstract

Although embolic protection devices reduce complications during saphenous vein graft (SVG) stenting, adverse events still occur in approximately 10% of patients. IIb/IIIa antagonists have not been proven effective during SVG intervention. We hypothesized that adjunctive use of these agents might enhance the efficacy of embolic protection devices. In the prospective, multicentre FilterWire EX Randomized Evaluation trial, 651 patients undergoing SVG stenting were randomized to either filter-based FilterWire EX or balloon occlusion/aspiration GuardWire embolic protection devices. IIb/IIIa inhibitor use was at the discretion of the investigator, with randomization stratified by intended use. Patients pre-selected for IIb/IIIa inhibitor use (n = 345) had higher baseline risk, with increased 30-day major adverse cardiac events (MACE, 13.0 vs. 8.0%, P = 0.03). GuardWire assigned patients treated with IIb/IIIa inhibitors had higher 30-day MACE compared with those not treated with IIb/IIIa inhibitors (16.0 vs. 6.3%, P = 0.007). In contrast, MACE in high-risk FilterWire patients treated with IIb/IIIa inhibitors were similar to their lower risk, untreated counterparts (9.9 vs. 9.5%, P = 0.89). Multivariable analysis detected a borderline significant (P = 0.056) interaction for lower MACE between FilterWire and IIb/IIIa inhibitor use. Adjustment by the propensity to use IIb/IIIa inhibitors resulted in a significant (P = 0.023) interaction for lower MACE rates. IIb/IIIa inhibition in conjunction with FilterWire was associated with less abrupt closure, no reflow, or distal embolization. IIb/IIIa antagonists may improve procedural outcome during SVG stenting in high risk patients, utilizing filter-based embolic protection devices.