Safety and effectiveness of mechanical thrombectomy for primary isolated distal vessel occlusions: A monocentric retrospective comparative study

Use of the pRESET LITE thrombectomy device in combined approach for medium vessel occlusions: A multicenter evaluation

PURPOSE

Our purpose was to assess the efficacy and safety of the pRESET LITE stent retriever (Phenox, Bochum, Germany), designed for medium vessel occlusion (MeVO) in acute ischemic stroke (AIS) patients with a primary MeVO.

METHODS

We performed a retrospective analysis of the MAD MT Consortium, an integration of prospectively maintained databases at 37 academic institutions in Europe, North America, and Asia, of AIS patients who underwent mechanical thrombectomy with the pRESET LITE stent retriever for a primary MeVO. We subcategorized occlusions into proximal MeVOs (segments A1, M2, and P1) vs. distal MeVOs/DMVO (segments A2, M3-M4, and P2). We reviewed patient and procedural characteristics, as well as angiographic and clinical outcomes.

RESULTS

Between September 2016 and December 2021, 227 patients were included (50% female, median age 78 [65-84] years), of whom 161 (71%) suffered proximal MeVO and 66 (29%) distal MeVO. Using a combined approach in 96% of cases, successful reperfusion of the target vessel (mTICI 2b/2c/3) was attained in 85% of proximal MeVO and 97% of DMVO, with a median of 2 passes (IQR: 1-3) overall. Periprocedural complications rate was 7%. Control CT at day 1 post-MT revealed a hemorrhagic transformation in 63 (39%) patients with proximal MeVO and 24 (36%) patients with DMVO, with ECASS-PH type hemorrhagic transformations occurring in 3 (1%) patients. After 3 months, 58% of all MeVO and 63% of DMVO patients demonstrated a favorable outcome (mRS 0-2).

CONCLUSION

Mechanical thrombectomy using the pRESET LITE in a combined approach with an aspiration catheter appears effective for primary medium vessel occlusions across several centers and physicians.

Endovascular therapy for acute ischemic stroke with distal medium vessel occlusion: a systematic review and meta-analysis

AIMS

Endovascular therapy (EVT) for distal medium vessel occlusions (DMVOs) is a potential frontier of acute ischemic stroke (AIS) treatment, but its efficacy against best medical therapy (BMT) remains unknown. We performed a systematic review and meta-analysis evaluating the efficacy and safety of EVT versus BMT in primary DMVO.

METHODS

We systematically searched PubMed, Cochrane Library and Embase, from inception to August 14, 2022, for studies comparing EVT with BMT in DMVO-AIS. We adopted the Distal Thrombectomy Summit Group's definition of DMVO. Efficacy outcomes were functional independence (90-day modified Rankin Scale (mRS) 0-2) and excellent functional outcomes (90-day mRS 0-1). Safety outcomes were symptomatic intracranial hemorrhage (sICH) and 90-day mortality.

RESULTS

Fourteen observational and two randomized-controlled studies were included, with 1202 patients receiving EVT and 1267 receiving BMT. After trim-and-fill correction, EVT achieved significantly better odds of functional independence than BMT (adjusted OR 1.61, 95% CI 1.06 to 2.43). There were no significant differences in overall excellent functional outcomes (OR 1.23, 95% CI 0.88 to 1.71), sICH (OR 1.44, 95% CI 0.78 to 2.66), and mortality (OR 1.03, 95% CI 0.73 to 1.45). Stratified by EVT method, mechanical thrombectomy±intra-arterial thrombolysis achieved more excellent functional outcomes than BMT (OR 1.59, 95% CI 1.13 to 2.23). In mild strokes (National Institutes of Health Stroke Scale score <6), EVT caused significantly more sICH (OR 6.30, 95% CI 1.55 to 25.64).

CONCLUSIONS

EVT shows promising efficacy benefit over BMT for primary DMVO-AIS. Further randomized controlled trials are necessary to evaluate the efficacy and safety of EVT in DMVO-AIS.

Endovascular therapy versus medical management for mild strokes due to medium and distal vessel occlusions

BACKGROUND

Distal and medium vessel occlusion (DMVO) strokes account for up to 40% of all acute ischemic strokes, many of which have a low initial deficit severity. Increasingly, endovascular treatment (EVT) is considered for these patients. However, there is a paucity of data comparing potential safety and efficacy of EVT versus best medical management (BMT) in these patients, particularly when presenting with mild symptoms.

METHODS

We retrospectively analyzed consecutive DMVO patients with NIHSS ≤6 who presented between January 2018 and December 2021 within 24 h from last seen well. We compared early and late clinical outcomes, as well as safety outcomes using multivariable linear and logistic regression analyses to determine whether EVT was independently associated with the outcomes of interest.

RESULTS

We included 80 subjects that fulfilled our study criteria (n = 41 BMT and n = 39 EVT). On adjusted analyses, when comparing EVT and BMT groups, there was no statistical difference in the NIHSS at discharge (Coefficient = -0.6, 95%-CI = -3.45-2.26, p = 0.678) or in the modified Rankin scale (mRS) at discharge (Coefficient = 0.37, 95%-CI = -0.52-1.25, p = 0.408). Furthermore, there was no difference in the 3-month mRS defined as good (mRS 0-2) (OR = 0.56, 95%-CI = 0.17-1.83, p = 0.341) or excellent (mRS 0-1) (OR = 0.45, 95%-CI = 0.15-1.34, p = 0.152). Finally, there was no difference in the incidence of all-type parenchymal hemorrhage (OR = 0.9, 95%-CI = 0.22-3.62, p = 0.879).

CONCLUSIONS

We found that among DMVO patients with low admission NIHSS treatment with EVT versus BMT was associated with similar outcomes. Larger prospective studies are required to confirm these findings.

Desired Qualities of Endovascular Tools and Barriers to Treating Medium Vessel Occlusion MeVO : Insights from the MeVO-FRONTIERS International Survey

BACKGROUND

Endovascular treatment (EVT) for stroke due to medium vessel occlusion (MeVO) can be technically challenging and specific endovascular tools are needed to safely and effectively recanalize these relatively small and fragile vessels. We aimed to gain insight into availability and desired qualities of endovascular devices used in MeVO stroke and examined barriers to adoption of MeVO EVT in clinical practice on a global scale.

METHODS

We conducted a case-based international survey among neurointerventionalists. As a part of the survey, participants were asked whether they felt appropriate endovascular tools for MeVO stroke exist and are available to them in their clinical practice. We then examined barriers to adopting MeVO EVT and analyzed them by geographic regions.

RESULTS

A total of 263 neurointerventionists participated, of which 178 (67.7%) and 83 (31.6%) provided responses on desired qualities of MeVO EVT tools and on barriers to their adoption in local practice, respectively. The majority 121/178 (68%) felt there was substantial room for improvement regarding existing tools. A large proportion 131/178 (73.6%) felt they had appropriate access to existing tools. The most commonly mentioned barrier for adopting MeVO EVT in North America was "awaiting better tools" (9/28 responses, 32.1%), while "awaiting better evidence" (8/26 responses, 30.8%), and the need for improved "funding" (7/26 responses, 26.9%) were important barriers in Europe.

CONCLUSION

The majority of surveyed neurointerventionalists felt that dedicated MeVO EVT tools can be substantially improved upon. Different regions face various challenges in adoption of MeVO EVT, but overall, physicians are mostly awaiting better MeVO EVT tools.