Randomized Evaluation of TriGuard 3 Cerebral Embolic Protection After Transcatheter Aortic Valve Replacement: REFLECT II

Objectives: The REFLECT II (Randomized Evaluation of TriGuard 3 Cerebral Embolic Protection After Transcatheter Aortic Valve Implantation) trial was designed to investigate the safety and efficacy of the TriGUARD 3 (TG3) cerebral embolic protection in patients undergoing transcatheter aortic valve replacement.

Background: Cerebral embolization occurs frequently following transcatheter aortic valve replacement and procedure-related ischemic stroke occurs in 2% to 6% of patients at 30 days. Whether cerebral protection with TriGuard 3 is safe and effective in reducing procedure-related cerebral injury is not known.

Methods: This prospective, multicenter, single-blind, 2:1 randomized (TG3 vs. no TG3) study was designed to enroll up to 345 patients. The primary 30-day safety endpoint (Valve Academic Research Consortium-2 defined) was compared with a performance goal (PG). The primary hierarchical composite efficacy endpoint (including death or stroke at 30 days, National Institutes of Health Stroke Scale score worsening in hospital, and cerebral ischemic lesions on diffusion-weighted magnetic resonance imaging at 2 to 5 days) was compared using the Finkelstein-Schoenfeld method.

Results: REFLECT II enrolled 220 of the planned 345 patients (63.8%), including 41 roll-in and 179 randomized patients (121 TG3 and 58 control subjects) at 18 US sites. The sponsor closed the study early after the U.S. Food and Drug Administration recommended enrollment suspension for unblinded safety data review. The trial met its primary safety endpoint compared with the PG (15.9% vs. 34.4% (p < 0.0001). The primary hierarchal efficacy endpoint at 30 days was not met (mean scores [higher is better]: -8.58 TG3 vs. 8.08 control; p = 0.857). A post hoc diffusion-weighted magnetic resonance imaging analysis of per-patient total lesion volume above incremental thresholds showed numeric reductions in total lesion volume >500 mm³ (-9.7%) and >1,000 mm³ (-44.5%) in the TG3 group, which were more pronounced among patients with full TG3 coverage: -51.1% (>500 mm³) and -82.9% (>1,000 mm³).

Conclusions: The REFLECT II trial demonstrated that the TG3 was safe compared with a historical PG but did not meet its pre-specified primary superiority efficacy endpoint.