Distal mechanical thrombectomy using beveled tip aspiration zoom catheters: A preliminary study.

Introduction: Distal medium vessel occlusion (DVO) thrombectomy has been shown to be efficacious with safety profiles comparable to large vessel occlusion (LVO) thrombectomy. A novel, highly-trackable, bevel-tipped Zoom 35 catheter can be used as an aspiration catheter for 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 35 catheter. Patient demographics, presenting and discharge NIHSS, primary and rescue thrombectomy, site of occlusion, TICI score, and intracranial hemorrhage were chart abstracted. Descriptive statistics were used to evaluate the efficacy and safety of thrombectomy.

Results: Fourteen patients (mean age 66.64 ± 13.75 years) were included. The mean NIHSS at presentation was 10.79 ± 5.48, and the mean ASPECTS was 9.00 ± 0.89. Nine patients (64.3%) received tPA. Primary occlusion location was M3 in nine cases (64.3%), M2/M3 junction in two cases (14.3%), A2 in one case (7.1%), A3 in one case (7.1%), and P1 in one case (7.1%). TICI scores were 3 in seven cases (50.0%), 2C in three cases (21.4%), and 2B in four cases (28.6%). There was one postoperative SAH (7.1%) and one asymptomatic ICH (7.1%). Mean discharge NIHSS was 3.38 ± 4.44, with a mean decrease of 7.31 from presentation (p < 0.0001, t-test).

Conclusion: Zoom 35 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.