Introduction: As occlusions in the distal cerebral vasculature are increasingly targeted for removal, distal access catheters (DACs) have been adapted for off-label aspiration thrombectomy. Although of potential utility in this area of the vasculature, DACs may carry additional risks. The FDA recently published a letter to providers that urges caution when using DACs for aspiration thrombectomy, emphasizing that DACs are distinct from aspiration thrombectomy catheters (ATCs), which are FDA cleared for this purpose. They made particular mention that the risks of off-label aspiration thrombectomy with DACs may be accentuated in the distal vasculature. In light of this, we evaluated the efficacy and safety of distal access catheters used for aspiration thrombectomy in the distal vasculature at our institution.
Methods: Using a prospectively acquired and maintained database all patients who underwent thrombectomy at our medical center between January 1, 2014 and March 1, 2017 were retrospectively screened for inclusion in the study. Patients were screened for: 1) occlusion location in the distal vasculature (M2 or more distal) and 2) direct thrombus aspiration attempt with a distal access catheter. Data including occlusion location, catheter type, postoperative complications, admission/discharge NIHSS scores, and final TICI revascularizations scores were recorded.
Results: The analysis included 8 patients. The median admission NIHSS was 17 (IQR 13 - 23.3). Occlusion locations included left M2 (6/8), right M2 (1/8), and left M3 (1/8). The distal access catheters employed included the Stryker Catalyst 6 (5/8), Penumbra Velocity (2/8), and the Sofia Plus (1/8). Direct thrombus aspiration was successful in 50% (4/8) cases, though final TICI 2b-3 was achieved in all patients. There were no instances of symptomatic intracranial hemorrhage. Median NIHSS at discharge was 5 (IQR 0.8, 15).
Conclusions: Aspiration thrombectomy with off-label distal access catheters may be safe and effective in the distal vasculature. In light of the recent FDA warning regarding off-label use, further evaluation of distal access catheters in this capacity is warranted.
Patient Care: Availability of a variety of catheters that may each have particular utility in certain clinical scenarios enhances the neurointerventionalist’s armamentarium.
Learning Objectives: By the conclusion of this session, participants should be able to 1) identify the differences between an aspiration thrombectomy catheter and a distal access catheter, 2) understand the FDA safety concerns of using DACs for aspiration thrombectomy, especially in the distal vasculature, and 3) recognize that DACs may, in fact, be safe for this aspiration thrombectomy.