Is Direct Endovascular Treatment as an Alternative of Bridging Therapy in Acute Stroke Patients with Large Vessel Occlusion?

Meta-analysis of direct endovascular thrombectomy vs bridging therapy in the management of acute ischemic stroke with large vessel occlusion

BACKGROUND

Debates persist when using intravenous thrombolysis (IVT) before mechanical thrombectomy (MT) for acute ischemic stroke (AIS) due to large-vessel occlusion (LVO). This systematic review and meta-analysis synthesized evidence on outcomes in patients with acute ischemic stroke due to large vessel occlusion (AIS-LVO), comparing bridging therapy (BT) with MT alone.

METHOD

We conducted searches of PubMed, Scopus, Web of Science, and the Cochrane Central Register of Controlled Trials from inception to July 2023 to identify pertinent clinical trials and observational studies.

RESULT

76 studies, involving 37,658 patients, revealed no significant difference in 90-day functional independence between DEVT and BT. However, a trend favoring BT for achieving functional independence with a modified Rankin Scale (mRS) of 0-1 was observed, having Odds ratio (OR) of 0.75 (95% CI 0.66-0.86; p < 0.001). DEVT was associated with higher postprocedural mortality (OR 1.44;95% CI 1.25-1.65; p < 0.001), but a lower risk of symptomatic intracranial hemorrhage compared to BT (OR 0.855; 95% CI 0.621-1.177; p = 0.327). Successful recanalization rates favored BT, emphasizing the importance of individualized treatment decisions (OR 0.759; 95% CI 0.594-0.969; p = 0.027). Sensitivity analyses were conducted to identify key contributors to heterogeneity.

CONCLUSION

Our meta-analysis underscores the intricate equilibrium between functional efficacy and safety in the evaluation of DEVT and BT for ACS-LVO. Fundamentally, while BT appears more efficacious, concerns about safety arise due to the superior safety profile demonstrated by DEVT. Individualized treatment decisions are imperative, and further trials are warranted to enhance precision in clinical guidance.

Clinical evidence comparing bridging and direct endovascular thrombectomy: progress and controversies

Clinical evidence comparing bridging endovascular thrombectomy (bEVT) with intravenous thrombolysis and direct endovascular thrombectomy (dEVT) without thrombolysis for patients with acute ischemic stroke (AIS) presented directly to an EVT-capable center is overwhelming but inconsistent. This study aimed to analyze the progress and controversies in clinical evidence based on current meta-analyses. Three databases, including MEDLINE, EMBASE, and the Cochrane Library, were searched. Relevant data were extracted and reviewed from the pooled studies. The Assessment of Multiple Systematic Review (AMSTAR-2) was used for quality assessment. Twenty-five meta-analyses were finally included. There were 56% (14/25) from Asian countries, 20% (5/25) from North America, and 24% (6/25) from Europe. The majority (72%, 18/25) of evidence arose in a short period from 2020 to 2022 with the serial publication of four randomized controlled trials (RCTs). Among the 25 meta-analyses, 11 pooled at least three RCTs but there is substantial overlap among seven (five recruited the same four RCTs solely and two recruited the same three RCTs solely). Meanwhile, quality rating based on AMSTAR-2 showed 16 'high' rated studies (64%). For functional independence, 40% (10/25) of studies favored bEVT and 60% showed neutral results. For symptomatic intracerebral hemorrhage, most studies (82.6%, 19/23) showed no significant difference. Non-RCT studies contributed to evidence favoring bEVT. Current RCTs provide an update of clinical evidence comparing bEVT and dEVT. However, they simultaneously contribute to an unnecessary overlap among studies. Contemporary observational studies demonstrated different but possibly confounded evidence. Thus, this issue still requires more clinical evidence under standard procedures.

Direct Mechanical Thrombectomy vs. Bridging Therapy in Stroke Patients in A “Stroke Belt” Region of Southern Europe

The aim of this 4-year observational study is to analyze the outcomes of stroke patients treated with direct mechanical thrombectomy (dMT) compared to bridging therapy (BT) (intravenous thrombolysis [IVT] + BT) based on 3-month outcomes, in real clinical practice in the "Stroke Belt" of Southern Europe. In total, 300 patients were included (41.3% dMT and 58.6% BT). The frequency of direct referral to the stroke center was similar in the dMT and BT group, whereas the time from onset to groin was longer in the BT group (median 210 [IQR 160–303] vs. 399 [IQR 225–675], p = 0.001). Successful recanalization (TICI 2b-3) and hemorrhagic transformation were similar in both groups. The BT group more frequently showed excellent outcomes at 3 months (32.4% vs. 15.4%, p = 0.004). Multivariate analysis showed that BT was independently associated with excellent outcomes (OR 2.7. 95% CI,1.2–5.9, p = 0.02) and lower mortality (OR 0.36. 95% CI 0.16–0.82, p = 015). Conclusions: Compared with dMT, BT was associated with excellent functional outcomes and lower 3-month mortality in this real-world clinical practice study conducted in a region belonging to the “Stroke Belt” of Southern Europe. Given the disparity of results on the benefit of BT in the current evidence, it is of vital importance to analyze the convenience of its use in each health area.

Intravenous Thrombolysis Before Mechanical Thrombectomy for Acute Ischemic Stroke: A Meta-Analysis

Background

Whether intravenous thrombolysis before mechanical thrombectomy provides additional benefit for functional outcome in acute ischemic stroke remains uncertain. We performed a meta‐analysis to compare the outcomes of direct mechanical thrombectomy (dMT) to mechanical thrombectomy with bridging using intravenous thrombolysis (bridging therapy [BT]) in patients with acute ischemic stroke.

Methods and Results

We performed a literature search in the PubMed, Excerpta Medica database, and Cochrane Central Register of Controlled Trials from January 1, 2003, to April 26, 2021. We included randomized clinical trials and observational studies that reported the 90‐day functional outcome in patients with acute ischemic stroke undergoing dMT compared with BT. The 12 included studies (3 randomized controlled trials and 9 observational studies) yielded 3924 participants (mean age, 68.0 years [SD, 13.1 years]; women, 44.2%; 1887 participants who received dMT and 2037 participants who received BT). A meta‐analysis of randomized controlled trial and observational data revealed similar 90‐day functional independence (odds ratio [OR], 1.04; 95% CI, 0.90–1.19), mortality (OR, 1.03; 95% CI, 0.78–1.36), and successful recanalization (OR, 0.93; 95% CI, 0.76–1.14) for patients treated with dMT or BT. Compared with those in the BT group, patients in the dMT group were less likely to experience symptomatic intracranial hemorrhage (OR, 0.68; 95% CI, 0.51–0.91; P=0.008) or any intracranial hemorrhage (OR, 0.71; 95% CI, 0.61–0.84; P<0.001).

Conclusions

In this meta‐analysis of patients with acute ischemic stroke, we found no significant differences in 90‐day functional outcome or mortality between dMT and BT, but a lower rate of symptomatic intracranial hemorrhage for dMT. These findings support the use of dMT without intravenous thrombolysis bridging therapy.

Registration

URL: https://www.crd.york.ac.uk/prospero/; Unique identifier: 42021234664.

Direct Endovascular Thrombectomy Alone vs. Bridging Thrombolysis for Patients with Acute Ischemic Stroke : A Meta-analysis

PURPOSE

Although the current guidelines recommend bridging thrombolysis (BT) therapy, which is intravenous thrombolysis (IVT) followed by endovascular thrombectomy (EVT), for patients with acute ischemic stroke from large vessel occlusion (AIS-LVO), the effectiveness and safety of IVT remain controversial. We performed a meta-analysis to demonstrate the non-inferiority of direct EVT alone (DEVT) compared to BT for the efficacy and safety in patients with AIS-LVO who were eligible for IVT.

METHODS

The literature was searched in big databases between 1 January 1990 and 1 April 2021. The search included both randomized clinical trials (RCTs) and nonrandomized studies (NRSs) that compared DEVT with BT for patients with AIS-LVO who were eligible for IVT (time from stroke onset ≤ 4.5 h). Only NRSs with good intergroup variable matching were included in the study. Outcomes measured included 90-day functional independence, mortality, symptomatic intracranial hemorrhage (sICH), and successful recanalization. The noninferiority margin for risk difference was set at 5% from the literature review.

RESULTS

Three RCTs (n = 1094) and four NRSs (n = 1366) were included in the meta-analysis. There were 1227 patients (49.9%) in the DEVT group and 1233 patients (50.1%) in the BT group. A statistically significant noninferiority of DEVT compared to BT was concluded in 90-day functional independence, mortality and successful reperfusion. Even in the sICH rate, DEVT group showed a superiority (risk difference, -2%; 95% confidence interval, -4 to -0.002%).

CONCLUSION

Evidence from RCTs and observational NRSs supports the use of DEVT (without IVT) as the first choice for treatment of patients with AIS-LVO within a time span of 4.5 h or less from stroke onset.

Comparison of Prior Bridging Intravenous Thrombolysis With Direct Endovascular Thrombectomy for Anterior Circulation Large Vessel Occlusion: Systematic Review and Meta-Analysis

Background: Whether bridging treatment combining intravenous thrombolysis (IVT) and endovascular thrombectomy (EVT) is superior to direct EVT alone for emergent large vessel occlusion (LVO) in the anterior circulation is unknown. A systematic review and a meta-analysis were performed to investigate and assess the effect and safety of bridging treatment vs. direct EVT in patients with LVO in the anterior circulation.

Methods: PubMed, EMBASE, and the Cochrane library were searched to assess the effect and safety of bridging treatment and direct EVT in LVO. Functional independence, mortality, asymptomatic and symptomatic intracranial hemorrhage (aICH and sICH, respectively), and successful recanalization were evaluated. The risk ratio and the 95% CI were analyzed.

Results: Among the eight studies included, there was no significant difference in the long-term functional independence (OR = 1.008, 95% CI = 0.845–1.204, P = 0.926), mortality (OR = 1.060, 95% CI = 0.840–1.336, P = 0.624), recanalization rate (OR = 1.015, 95% CI = 0.793–1.300, P = 0.905), and the incidence of sICH (OR = 1.320, 95% CI = 0.931–1.870, P = 0.119) between bridging therapy and direct EVT. After adjusting for confounding factors, bridging therapy showed a lower recanalization rate (effect size or ES = −0.377, 95% CI = −0.684 to −0.070, P = 0.016), but there was no significant difference in the long-term functional independence (ES = 0.057, 95% CI = −0.177 to 0.291, P = 0.634), mortality (ES = 0.693, 95% CI = −0.133 to 1.519, P = 0.100), and incidence of sICH (ES = −0.051, 95% CI = −0.687 to 0.585, P = 0.875) compared with direct EVT. Meanwhile, in the subgroup analysis of RCT, no significant difference was found in the long-term functional independence (OR = 0.927, 95% CI = 0.727–1.182, P = 0.539), recanalization rate (OR = 1.331, 95% CI = 0.948–1.867, P = 0.099), mortality (OR = 1.072, 95% CI = 0.776–1.481, P = 0.673), and sICH incidence (OR = 1.383, 95% CI = 0.806–2.374, P = 0.977) between patients receiving bridging therapy and those receiving direct DVT.

Conclusion: For stroke patients with acute anterior circulation occlusion and who are eligible for intravenous thrombolysis, there is no significant difference in the clinical effect between direct EVT and bridging therapy, which needs to be verified by more randomized controlled trials.