Background Distal vessel occlusion (DVO) thrombectomy (M3, A2, P2, and beyond) has shown promising outcomes and safety profiles comparable to large vessel occlusion thrombectomy.¹ Simple aspiration is associated with lower rates of symptomatic intracranial hemorrhage than stent-retriever.² Novel, highly trackable bevel tipped .035 aspiration microcatheters (‘Zoom 0.035’) are promising for reperfusion of both de novo and rescue DVO thrombectomy.

Methods This is a retrospective single-arm, multi-institutional observational study evaluating the efficacy and safety of aspiration thrombectomy for DVO using the Zoom .035 microcatheter. Information regarding patient demographics, presenting/discharge NIHSS, primary/rescue thrombectomy, site of occlusion, TICI score, and intracranial hemorrhage was chart abstracted. Descriptive statistics were used to evaluate the efficacy of thrombectomy both clinically and radiographically.

Results Fifteen patients (8 male [53.3%]; mean age 65.5±14.0 years) underwent aspiration thrombectomy of DVO using the Zoom .035 microcatheter. The mean NIHSS at presentation was 11±5.3, and the mean ASPECTS was 9.1±0.9. Nine patients (60%) received tPA. Primary occlusion location was M3 in eleven cases (73.3%), V4 VA in one case (6.7%), A2 in one case (6.7%), A3 in one case (6.7%), and P1 in one case (6.7%). Rescue treatment (distal thrombectomy performed following aspiration of a more proximal lesion) occurred in 2/15 cases (13.3%), M3 in one case and P2 in the other. TICI scores were 3 in eight cases (53.3%), 2c in three case (20%), and 2b in four cases (26.7%). There was one postoperative SAH (6.7%) and one ICH (6.7%) that was asymptomatic. Mean discharge NIHSS was 1.9±2.7, with a mean decrease of 7.4±4.5 from presentation (p<0.0001, T-test). Mean length of stay was 4.2±1.6 days. 8/10 patients (80%) had an mRS of 0-2 at 90-day follow-up, with a mean mRS of 1.2±1.8. There was one mortality due to GI bleeding and V-fib arrest.Conclusion: Zoom .035 beveled-tip aspiration microcatheters are highly trackable and associated with improved radiographic and clinical outcomes for the treatment of DVO with a good safety profile.

References

1. Alawieh AM, Chalhoub RM, Al Kasab S, et al. Multicenter investigation of technical and clinical outcomes after thrombectomy for distal vessel occlusion by frontline technique. J Neurointerv Surg. 2022.

2. Grieb D, Greling B, Schulz K, et al. Endovascular treatment of distal medium vessel occlusions using microcatheter aspiration thrombectomy. Interv Neuroradiol. 2022:15910199221133470.

Disclosures V. Nguyen: None. J. Dallas: None. J. Sequeiros Chirinos: None. S. Graham: None. J. Burns-Martin: None. N. Goyal: None. K. Khatibi: None.