Intravenous Alteplase is Associated with First Pass Effect in Stent-retriever but not ADAPT Thrombectomy : Post Hoc Analysis of the SKIP Study

Feasibility, efficacy, and safety of mechanical thrombectomy via sheathless transradial access as a first-line strategy: A case series

OBJECTIVE

Although mechanical thrombectomy (MT) is primarily performed via transfemoral access (TFA), transradial access (TRA) is a potential alternative in older patients or those with tortuous vessels. However, the small radial artery diameter restricts the use of large-bore balloon guides and aspiration catheters, a limitation that may be overcome using the sheathless technique. Thus, we aimed to explore the feasibility, efficacy, and safety of sheathless TRA-MT as a first-line treatment approach for acute ischemic stroke.

METHODS

This single-center retrospective case series included patients who underwent TRA-MT as first-line treatment between September 2020 and June 2023. Per our MT protocol, TRA was not the first-line approach in cases of left anterior circulation lesions with a type 3 aortic arch. We evaluated treatment effectiveness based on the successful recanalization rate, puncture-to-recanalization time, and modified first-pass effect; access route effectiveness based on the puncture-to-first-pass time and switch-to-TFA rate; and procedure safety based on procedure-related and severe puncture site complications.

RESULTS

Sheathless 8-F guide catheters were used in 68 % and large-bore aspiration catheters in 70 % of the procedures. Successful recanalization was achieved in 98 % of the patients, with a modified first-pass effect in 54 % of them. The median puncture-to-first-pass and puncture-to-recanalization times were 20.5 and 33 min, respectively. The rate of procedure-related complications was low (4 %), with no severe puncture site complications.

CONCLUSION

Sheathless TRA-MT enabled the use of large-bore guide and aspiration catheters, providing a swift approach to the target and satisfactory outcomes, and might be an effective first-line treatment for acute ischemic stroke.

Effect of Bridging Thrombolysis on the Efficacy of Stent Retriever Thrombectomy Techniques : Insights from the SWIFT-DIRECT trial

BACKGROUND

There are little available data regarding the influence of intravenous thrombolysis (IVT) on the efficacy of different first line endovascular treatment (EVT) techniques.

METHODS

We used the dataset of the SWIFT-DIRECT trial which randomized 408 patients to IVT + EVT or EVT alone at 48 international sites. The protocol required the use of a stent retriever (SR), but concomitant use of a balloon guide catheter (BGC) and/or distal aspiration (DA) catheter was left to the discretion of the operators. Four first line techniques were applied in the study population: SR, SR + BGC, SR + DA, SR + DA + BGC. To assess whether the effect of allocation to IVT + EVT versus EVT alone was modified by the first line technique, interaction models were fitted for predefined outcomes. The primary outcome was first pass mTICI 2c‑3 reperfusion (FPR).

RESULTS

This study included 385 patients of whom 172 were treated with SR + DA, 121 with SR + DA + BGC, 57 with SR + BGC and 35 with SR. There was no evidence that the effect of IVT + EVT versus EVT alone would be modified by the choice of first line technique; however, allocation to IVT + EVT increased the odds of FPR by a factor of 1.68 (95% confidence interval, CI 1.11-2.54).

CONCLUSION

This post hoc analysis does not suggest treatment effect heterogeneity of IVT + EVT vs EVT alone in different stent retriever techniques but provides evidence for increased FPR if bridging IVT is administered before stent retriever thrombectomy.

Effects of intravenous thrombolysis on stent retriever and aspiration thrombectomy outcomes: a systematic review and meta-analysis of the randomized controlled trials

BACKGROUND

Risks and benefits of intravenous thrombolysis (IVT) in patients undergoing mechanical thrombectomy (MT) have been a topic of interest. However, IVT's specific effects on stent retriever (SR) and aspiration thrombectomy (ASP) outcomes remain largely unexplored. In this meta-analysis, we aimed to investigate the effects of IVT on SR and ASP thrombectomy outcomes.

METHODS

In accordance with PRISMA guidelines, a systematic literature review was conducted using Medline, Embase, Scopus, Web of Science, and Cochrane Center of Clinical Trials databases. Outcomes of interest included successful recanalization (modified Thrombolysis In Cerebral Infarction (mTICI) ≥2b), modified first pass efficacy (mFPE), functional independence (modified Rankin Scale (mRS) ≤2), symptomatic intracranial hemorrhage (sICH), and embolization to new territories (ENT).

RESULTS

Four randomized controlled trials with 1176 patients were included. SR and ASP resulted in similar mTICI ≥2b, mFPE, and mRS 0-2 rates in patients with and without IVT administration. SR without IVT was associated with a significantly lower rate of mFPE compared with the SR+IVT (RR 0.85, 95% CI 0.74 to 0.97). Furthermore, ASP without IVT resulted in a lower rate of mRS 0-2 than the ASP+IVT with a strong trend towards significance (RR 0.78, 95% CI 0.60 to 1.01). Finally, bridging therapy did not increase sICH and ENT rates after ASP or SR thrombectomy.

CONCLUSIONS

Our findings suggest that SR and ASP thrombectomy have comparable safety and efficacy profiles, regardless of prior IVT administration. Additionally, our results indicate that the addition of IVT may improve certain efficacy outcomes based on the employed first-line MT technique.

Predictive Factors of First-Pass Effect in Patients Who Underwent Successful Endovascular Thrombectomy for Emergent Large Vessel Occlusion

OBJECTIVE

The primary treatment goal of current endovascular thrombectomy (EVT) for emergent large-vessel occlusion (ELVO) is complete recanalization after a single maneuver, referred to as the 'first-pass effect' (FPE). Hence, we aimed to identify the predictive factors of FPE and assess its effect on clinical outcomes in patients with ELVO of the anterior circulation.

METHODS

Among the 129 patients who participated, 110 eligible patients with proximal ELVO (intracranial internal carotid artery and proximal middle cerebral artery) who achieved successful recanalization after EVT were retrospectively reviewed. A comparative analysis between patients who achieved FPE and all others (defined as a non-FPE group) was performed regarding baseline characteristics, clinical variables, and clinical outcomes. Multivariate logistic regression analyses were subsequently conducted for potential predictive factors with p<0.10 in the univariate analysis to determine the independent predictive factors of FPE.

RESULTS

FPE was achieved in 31 of the 110 patients (28.2%). The FPE group had a significantly higher level of functional independence at 90 days than did the non-FPE group (80.6% vs. 50.6%, p=0.002). Pretreatment intravenous thrombolysis (IVT) (odds ratio [OR], 3.179; 95% confidence interval [CI], 1.025-9.861; p=0.045), door-to-puncture (DTP) interval (OR, 0.959; 95% CI, 0.932-0.987; p=0.004), and the use of balloon guiding catheter (BGC) (OR, 3.591; 95% CI, 1.231-10.469; p=0.019) were independent predictive factors of FPE.

CONCLUSION

In conclusion, pretreatment IVT, use of BGC, and a shorter DTP interval were positively associated with FPE, increasing the chance of acquiring better clinical outcomes.

Devices and Techniques

This extensive review explores the intricacies of the three principal mechanical thrombectomy techniques: the stent retriever technique, contact aspiration technique, and a combined approach, and their application in managing acute ischemic stroke. Each technique operates uniquely on the thrombus, leading to differences in their efficacy. Factors including clot size, clot stiffness, vessel tortuosity, and the angle of interaction between the aspiration catheter and the clot significantly influence these differences. Clinical trials and meta-analyses have shown the overall equivalency of these techniques for the treatments of large vessel occlusion and distal medium vessel occlusions. However, there are nuanced differences that emerge under specific clinical circumstances, highlighting the absence of a one-size-fits-all strategy in acute ischemic stroke management. We emphasize the need for future investigations to elucidate these nuances further, aiming to refine procedural strategies and individualize patient care for optimal outcomes.

[Neurothrombectomy 2022-Extension of indications and technical innovations]

For advanced territorial ischemia numerous retrospective and prospective studies have shown a positive effect of mechanical thrombectomy (MT) compared to best medicinal treatment alone. For patients with minor stroke (NIHSS < 6) there is currently a lack of evidence for MT. Appropriate study protocols must differentiate between patients with large vessel occlusion with disproportionately mild symptoms and more distal vascular occlusion and therefore correspondingly fewer clinical symptoms. The role of intravenous lysis treatment before MT as bridging lysis also currently retains its general recommendation, as large studies could not show a uniform noninferiority of MT alone. In addition, the use of intra-arterial lysis after successful MT offers a promising approach, which still needs to be evaluated. Novel aspiration catheters and stent-retrievers as well as competing thrombectomy techniques can be compared by the first pass effect, the successful recanalization with only one attempt at thrombectomy. Contact aspiration and stent-retriever thrombectomy under aspiration are equivalent and established thrombectomy procedures. For the latter, several detailed maneuver tactics are described for improvement of thrombectomy success. Also, in retrospective studies the combination with a balloon-guided catheter promises a further improvement of recanalization results. In the case of failure of supra-aortic vessel probing with inguinal access, radial access and direct carotid puncture are alternative access routes. Recent studies on ICA stenting with tandem occlusions showed a benefit of stents without an increased risk for symptomatic intracranial hemorrhage. The retrograde approach, to first treat the intracranial vessel occlusion and then the carotid stenosis, seems to be advantageous.