The PROXIMAL Trial: Proximal Protection During Saphenous Vein Graft Intervention Using the Proxis Embolic Protection System. A Randomized, Prospective, Multicenter Clinical Trial

Objectives: To determine if outcomes could be further improved, we investigated an embolic protection device placed proximal to the target lesion that could provide protection before lesion instrumentation, allow the use of conventional guidewires, and permit embolic protection in anatomy unfavorable for distal devices. Background: Embolic complications during stenting of degenerated saphenous vein coronary bypass grafts are reduced, but not eliminated, by distal protection. Methods: A total of 594 patients undergoing stenting of 639 saphenous vein grafts were prospectively randomized, using a noninferiority design, to compare 2 treatment strategies: control (distal protection whenever possible) or test (proximal protection when possible, distal when not). Results: The primary composite end point of death, myocardial infarction, or target vessel revascularization at 30 days by intention to treat analysis occurred in 10.0% of control and 9.2% of test patients; difference = -0.8% (95% confidence interval [CI] -5.5% to 4.0%); p for noninferiority = 0.0061. In device specific analysis, this composite end point occurred in 11.7% of distal protection patients and 7.1% of proximal protection patients (difference = -4.6% [95% CI -9.6% to 0.3%]; p for superiority = 0.10, p for noninferiority = 0.001). Finally, in the subset of patients with lesions amenable to treatment with either proximal or distal protection devices (n = 410), the primary composite end point occurred in 12.2% of distal protection patients and 7.4% of proximal protection patients; difference = -4.7% (95% CI -10.4% to 1.0%), p for superiority = 0.14, p for noninferiority = 0.001. Conclusions: Using proximal embolic protection whenever possible during treatment of diseased saphenous vein grafts produced outcomes similar to those with distal embolic protection.