Contemporary Results of Mechanical Thrombectomy and Impact of First-Line Technique on Outcome: The INSPIRE-S Global Registry.

Background And Purpose: Three mechanical thrombectomy (MT) techniques are predominantly used for the treatment of acute ischemic stroke (AIS): stent retriever (SR) alone, aspiration (ASP) alone, and combination therapy (CT) with a general goal of achieving first-pass reperfusion (FPR: eTICI≥2c). Factors influencing FPR and the relative efficacy and safety of the 3 techniques are loosely understood.

Materials And Methods: INSPIRE-S is a prospective, imaging core-lab adjudicated, safety clinical events committee adjudicated, global registry of AIS patients treated with Medtronic Neurovascular devices on the first pass and grouped according to first-pass MT technique.

Results: From May 2020 through December 2022, 802 patients (29 sites, 13 countries) who met eligibility criteria were enrolled in the INSPIRE-S registry and were grouped by first-pass MT technique (259 in SR, 146 in ASP, and 397 in CT). Overall, MCA-M1/M2 occlusions were present in 76.1% of patients, and the mean number of passes was 1.9±1.3. Among the techniques, the primary endpoint, good clinical outcome (mRS≤ 2 or mRS≤ pre-stroke mRS) at 90 days was achieved in 60.5% in SR, 52.8% in ASP, and 56.6% in CT (p>0.05 in unadjusted and adjusted analyses). The FPR rates were 48.6% in SR, 39.9% in ASP, and 47.5% in CT (p>0.05), and final complete (eTICI≥2c) reperfusion rates were 77.4% in SR, 70.6% in ASP, and 72.0% in CT (p>0.05 in adjusted analyses). In subgroup analyses by occlusion location, ASP had the lowest FPR in the ICA (p=0.003), while ASP was more frequently employed than SR for ICA (p=0.03). There was no significant difference in FPR among techniques when patients were treated with site-preferred technique. The overall rates of CEC-adjudicated all-cause mortality (14.0%) and sICH (1.5%) did not significantly differ among the techniques.

Conclusions: The primary results of real-world data from INSPIRE-S showed overall high rates of first pass complete reperfusion and final clinical outcomes that were similar among the 3 MT techniques.

Abbreviations: AIS＝ Acute Ischemic Stroke; CT＝ Combined technique; ASP＝ Aspiration alone; LVO＝ Large vessel occlusion; MT＝ Mechanical Thrombectomy; SR＝ Stent Retriever alone.