Distal embolic protection use during transfemoral carotid artery stenting is associated with improved in-hospital outcomes
OBJECTIVE: Despite current guidelines recommending the use of distal embolic protection during transfemoral carotid stenting (tfCAS) to prevent periprocedural stroke, there remains significant variation in the routine use of distal filters. We sought to assess in-hospital outcomes in patients undergoing tfCAS with and without embolic protection using a distal filter. METHODS: We identified all patients undergoing tfCAS in the VQI from March 2005-December 2021 and excluded those who received proximal embolic balloon protection. We created propensity score-matched cohorts of patients who underwent tfCAS with and without attempted placement of a distal filter. Subgroup analyses of patients with failed vs successful filter placement and failed vs no attempt at filter placement were performed. In-hospital outcomes were assessed using log binomial regression, adjusted for protamine use. Outcomes of interest were composite stroke/death, stroke, death, myocardial infarction (MI), transient ischemic attack (TIA), and hyperperfusion syndrome. RESULTS: Among 29,853 patients who underwent tfCAS, 28,213 (95%) had a filter attempted for distal embolic protection and 1640 (5%) did not. After matching, 6859 patients were identified. No attempted filter was associated with significantly higher risk of in-hospital stroke/death (6.4% vs 3.8%; aRR 1.72[1.32-2.23], p<.001), stroke (3.7% vs 2.5%; aRR 1.49[1.06-2.08], p=.022) and mortality (3.5% vs 1.7%; aRR 2.07[1.42-3.020], p<.001). In a secondary analysis of patients who had failed attempt at filter placement versus successful filter placement, failed filter placement was associated with worse outcomes (stroke/death: 5.8% vs 2.7%, aRR:2.10[1.38-3.21], p=.001 and stroke: 5.3% vs 1.8%, aRR: 2.87[1.78-4.61], p<.001). However, there were no differences in outcomes in patients with failed vs no attempted filter placement (stroke/death: 5.4% vs 6.2%, aRR: 0.99[0.61-1.63], p=.99; stroke: 4.7% vs 3.7%, aRR: 1.40[0.79-2.48], p=.20; death: 0.9% vs 3.4%, aRR: 0.35[0.12-1.01], p=0.052). CONCLUSIONS: Tfcas performed without attempted distal embolic protection was associated with a significantly higher risk of in-hospital stroke and death. Patients undergoing tfCAS after failed attempt at filter placement have equivalent stroke/death to patients in whom no filter was attempted, but more than a two-fold higher risk of stroke/death compared to those with successfully placed filters. These findings support current SVS guidelines recommending routine use of distal embolic protection during tfCAS. If a filter cannot be placed safely, an alternative approach to carotid revascularization should be considered.