Cyclical Aspiration Using a Novel Mechanical Thrombectomy Device is Associated with a High TICI 3 First Pass Effect in Large-vessel Strokes

Background And Purpose: Complete reperfusion (TICI 3) after the first thrombectomy attempt or first pass effect (FPE) is associated with best clinical outcomes in large-vessel occlusion (LVO) acute ischemic stroke. While endovascular therapy techniques have improved substantially, FPE remains low (24-30%), and new methods to improve reperfusion efficiency are needed.

Methods: In a prospective observational cohort study, 40 consecutive patients underwent cyclical aspiration thrombectomy using CLEAR Aspiration System (Insera Therapeutics Inc., Dallas, TX). Primary outcome included FPE with complete/near-complete reperfusion (TICI 2c/3 FPE). Secondary outcomes included early neurological improvement measured by the National Institute of Health Stroke Scale (NIHSS), safety outcomes, and functional outcomes using modified Rankin Scale (mRS). Outcomes were compared against published historical controls.

Results: Among 38 patients who met criteria for LVO, median age was 75 (range 31-96). FPE was high (TICI 3: 26/38 [68%], TICI 2c/3: 29/38 [76%]). Among anterior circulation strokes, core lab-adjudicated FPE remained high (TICI 3: 17/29 [59%], TICI 2c/3: 20/29 [69%]), with excellent final successful revascularization results (Final TICI 3: 24/29 [83%], Final TICI 2c/3: 27/29 [93%]). FPE in the CLEAR-1 cohort was significantly higher compared to FPE using existing devices (meta-analysis) from historical controls (TICI 2c/3: 76% vs. 28%, p = 0.0001). High rates of early neurological improvement were observed (delta NIHSS≥4: 35/38 [92.1%]; delta NIHSS≥10: 27/38 [71%]). Similarly, high rates of good functional outcomes (mRS 0-2: 32/38 [84%]) and low mortality (2/38 [5%]) were observed.

Conclusion: Cyclical aspiration using the CLEAR Aspiration System is safe, effective, and achieved a high TICI 3 FPE for large-vessel strokes.