Endovascular Thrombectomy With or Without Intravenous Thrombolysis: A Meta-Analysis of Randomized Controlled Trials

BACKGROUND

We performed this meta-analysis of randomized clinical trials to compare the outcomes in patients treated with endovascular thrombectomy who receive prior intravenous thrombolysis with those who do not receive such treatment. Recently, one randomized trial reported outcomes to address this issue, so timely update of meta-analysis is needed to determine the value of administering intravenous thrombolysis before endovascular thrombectomy.

MATERIALS AND METHODS

Four randomized clinical trials are included in our meta-analysis. We calculated pooled odds ratios and 95% CIs using random-effects models. The primary efficacy endpoint was a favorable outcome defined by a modified Rankin Scale score of 0 (no symptoms), 1 (no significant disability), or 2 (slight disability) at 90 days post-randomization. Secondary endpoints analyzed were any intracerebral hemorrhage, symptomatic intracerebral hemorrhage, and mortality.

RESULTS

Of the 1633 patients randomized, the proportion of patients who achieved a favorable outcome was similar between endovascular thrombectomy alone and combined approach with intravenous thrombolysis and endovascular thrombectomy (1631 patients analyzed; odds ratio 1.02; CI 0.84-1.25; p = 0.83). Risk of any intracerebral hemorrhage was significantly lower among those randomized to endovascular thrombectomy alone (1633 patients analyzed; odds ratio 0.75; CI 0.57-0.99; p = 0.04). Rates of symptomatic intracerebral hemorrhage (p = 0.36) and mortality (p = 0.62) were not significantly different between the two groups.

CONCLUSIONS

Compared with endovascular thrombectomy preceded by intravenous thrombolysis, endovascular thrombectomy resulted in similar rates of favorable outcome with a lower rate of intracerebral hemorrhage. A large phase 3 trial is required to conclusively demonstrate equivalency of both approaches to guide future practice.

Mechanical Thrombectomy with or without Intravenous Thrombolysis in Acute Ischemic Stroke: A Meta-Analysis for Randomized Controlled Trials

INTRODUCTION

The combination of mechanical thrombectomy (MT) and intravenous thrombolysis (IVT) is more effective than IVT alone in patients with large vessel occlusion, which has been proven in recent studies. However, there are still debates over whether IVT benefits patients treated with only direct mechanical thrombectomy (dMT).

METHODS

PubMed, Embase, and Cochrane Library were searched on June 15, 2021, for randomized controlled trials (RCTs). Seven RCTs with 2,143 patients were enrolled in our study.

RESULTS

MT combined with IVT had comparable efficacy and safety outcome compared with dMT in proximal anterior circulation occlusion at 90 days. For the primary outcome, pooled data showed no significant difference in the modified Rankin Scale (mRS) 0-2 at 90 days between the dMT and MT+IVT groups (pooled odds ratio 0.96, 95% confidence interval, 0.79, 1.17, p = 0.39). As for the mRS score 0-1 at 90 days, the degree of benefit conferred by dMT was substantial: for every 100 patients treated, the number of patients which had an excellent outcome in the dMT group was 10 higher than that of the MT+IVT group.

CONCLUSION

In this meta-analysis including 7 RCTs, MT had comparable consequences to bridging treatment in efficacy and safety outcomes for patients with ischemic stroke caused by the occlusion of proximal anterior circulation, irrespective of geographical location. These findings support the adoption of dMT in acute ischemic stroke treatments and have higher cost-effectiveness in global applications.

A nephroprotective iodinated contrast agent with cardioprotective properties: A pilot study

BACKGROUND AND PURPOSE

Evaluation and treatment of acute ischemic syndromes, in the heart and brain, require vessel visualization by iodinated X-ray contrast agents. However, these contrast agents can induce injury, in both the kidneys and target organs themselves. Sulfobutylether beta cyclodextrin (SBECD) added to iohexol (SBECD-iohexol) (Captisol Enabled-iohexol, Ligand Pharmaceuticals, Inc, San Diego, CA) is currently in clinical trials in cardiovascular procedures, to determine its relative renal safety in high-risk patients. Preclinical studies showed that SBECD-iohexol reduced contrast-induced acute kidney injury in rodent models by blocking apoptosis. The current study was undertaken to determine whether SBECD-iohexol is also cardioprotective, in the male rat ischemia-reperfusion model, compared to iohexol alone.

METHODS

After anesthesia, the left coronary artery was ligated for 30 min and the ligation released and reperfusion followed for 2 h prior to sacrifice. Groups 1-4 were injected in the tail vein 10 min prior to ischemia with: (1) vehicle; (2) iohexol; (3) SBECD; and (4) SBECD-iohexol. Infarct size, hemodynamics, and serum markers were measured.

RESULTS

An eight-fold increase in serum creatine kinase in the iohexol-alone group was observed, compared with no increase in the SBECD-iohexol group. The mean arterial pressure and rate pressure product were depressed in the iohexol-alone group, but not in the SBECD-iohexol group, or controls. No difference in infarct size or serum creatinine among the groups was observed.

CONCLUSION

The results of this study suggest that SBECD-iohexol is superior to iohexol alone, for both the preservation of cardiomyocyte integrity and preservation of myocardial function in myocardial ischemia.

Mechanical thrombectomy with or without thrombolysis: A meta-analysis of RCTs

BACKGROUND

Mechanical thrombectomy (MT) is effective in treating ischemic strokes due to large vessel occlusion. However, the risk-benefit ratio of intravenous thrombolysis (IVT) prior to MT is still unclear. Aim of the study was to provide a pooled analysis of only randomized controlled trials (RCTs) comparing direct MT (dMT) vs bridging treatment (IVT+MT).

METHODS

PubMed, EMBASE and Cochrane Central were searched only for RCTs comparing IVT+MT vs dMT in ischemic stroke patients. Primary endpoint was functional independence at 90 days (mRS<3), while secondary endpoints were represented by successful recanalization (TICI>2a), mortality at 90 days and symptomatic intracranial hemorrhage (sICH). Odds ratios for endpoints were pooled with meta-analysis and compared between reperfusion strategies.

RESULTS

The pooled analysis comprised 5 studies (n. patients = 1657). The rates for the primary endpoint were 39% and 34.5% for dMT and IVT+MT, respectively (OR 1.06; 95%CI 0.80-1.40). For the secondary endpoints, we did not observe significant differences between groups, even if the rate of successful recanalization was higher in IVT+MT treated patients (OR: 0.58; 95%CI 0.26-1.30;p_{heterogeneity} = 0.002), without a significant increase in sICH rates (4.3% vs 5.5%; OR: 0.96; 95%CI 0.43-2.13;p_{heterogeneity} = 0.26). Finally, mortality rates were 19.8% and 15.9% for dMT and IVT+MT, respectively.

CONCLUSIONS

In this meta-analysis including only RCTs, dMT and bridging treatment were substantially equivalent for good functional outcome. IVT+MT was associated to higher rates of successful recanalization, even if not significant. Therefore, further adequately powered RCTs comparing dMT vs IVT+MT are warranted.

Bridging Therapy and Occlusion Site Influence Symptomatic Hemorrhage Rate after Thrombectomy: A Daily Practice Study in 623 Stroke Patients

BACKGROUND

Comparison of symptomatic intracranial hemorrhage (SICH) rates between stroke patients treated with bridging therapy (BT) and primary mechanical thrombectomy (PMT) are scarce and difficult to interpret due to baseline differences between both populations.

METHODS

Retrospective analysis of patients with acute ischemic stroke treated with endovascular therapy (BT or PMT) was performed at our center between January 2010 and June 2017.

RESULTS

Six hundred twenty-three patients were included. Global SICH rate was 9% overall: 6.8% in the PMT group and 12.6% in the BT group. The following factors significantly associated with SICH after multivariate analysis: MCA occlusion (p: 0.047), stroke of unknown origin (p: 0.025), BT (p: 0.024), and procedural time over 65 min (p: 0.027). The following variables presented a statistically significant higher frequency in patients treated with PMT: atrial fibrillation (p: 0.005), anticoagulant medication (p < 0.001), wake-up strokes (p < 0.001), atherothrombotic etiology (p < 0.05), combined thrombectomy technique (p: 0.008), longer procedural times (p: 0.025), and favorable outcome at 3 months (p: 0.011). The following variables presented a statistically significant higher frequency in patients treated with BT: antiplatelet medication (p: 0.048), MCA occlusions (p: 0.017), cardioembolic etiology (p < 0.05), stent retriever/aspiration technique (p: 0.008), and SICH (p: 0.013). Patients with MCA occlusions had twice the risk of SICH after BT than after PMT (16.4 and 8.6%, p: 0.038).

CONCLUSIONS

In this clinical series, the SICH rate was higher in patients treated with BT than in those treated with PMT. Relevant differences in baseline (related to IVT contraindications) were found between both groups. Randomized studies of BT versus PMT in populations with similar baseline characteristics might be of interest.

Effect of Mechanical Thrombectomy Without vs With Intravenous Thrombolysis on Functional Outcome Among Patients With Acute Ischemic Stroke: The SKIP Randomized Clinical Trial

IMPORTANCE

Whether intravenous thrombolysis is needed in combination with mechanical thrombectomy in patients with acute large vessel occlusion stroke is unclear.

OBJECTIVE

To examine whether mechanical thrombectomy alone is noninferior to combined intravenous thrombolysis plus mechanical thrombectomy for favorable poststroke outcome.

DESIGN, SETTING, AND PARTICIPANTS

Investigator-initiated, multicenter, randomized, open-label, noninferiority clinical trial in 204 patients with acute ischemic stroke due to large vessel occlusion enrolled at 23 hospital networks in Japan from January 1, 2017, to July 31, 2019, with final follow-up on October 31, 2019.

INTERVENTIONS

Patients were randomly assigned to mechanical thrombectomy alone (n = 101) or combined intravenous thrombolysis (alteplase at a 0.6-mg/kg dose) plus mechanical thrombectomy (n = 103).

MAIN OUTCOMES AND MEASURES

The primary efficacy end point was a favorable outcome defined as a modified Rankin Scale score (range, 0 [no symptoms] to 6 [death]) of 0 to 2 at 90 days, with a noninferiority margin odds ratio of 0.74, assessed using a 1-sided significance threshold of .025 (97.5% CI). There were 7 prespecified secondary efficacy end points, including mortality by day 90. There were 4 prespecified safety end points, including any intracerebral hemorrhage and symptomatic intracerebral hemorrhage within 36 hours.

RESULTS

Among 204 patients (median age, 74 years; 62.7% men; median National Institutes of Health Stroke Scale score, 18), all patients completed the trial. Favorable outcome occurred in 60 patients (59.4%) in the mechanical thrombectomy alone group and 59 patients (57.3%) in the combined intravenous thrombolysis plus mechanical thrombectomy group, with no significant between-group difference (difference, 2.1% [1-sided 97.5% CI, -11.4% to ∞]; odds ratio, 1.09 [1-sided 97.5% CI, 0.63 to ∞]; P = .18 for noninferiority). Among the 7 secondary efficacy end points and 4 safety end points, 10 were not significantly different, including mortality at 90 days (8 [7.9%] vs 9 [8.7%]; difference, -0.8% [95% CI, -9.5% to 7.8%]; odds ratio, 0.90 [95% CI, 0.33 to 2.43]; P > .99). Any intracerebral hemorrhage was observed less frequently in the mechanical thrombectomy alone group than in the combined group (34 [33.7%] vs 52 [50.5%]; difference, -16.8% [95% CI, -32.1% to -1.6%]; odds ratio, 0.50 [95% CI, 0.28 to 0.88]; P = .02). Symptomatic intracerebral hemorrhage was not significantly different between groups (6 [5.9%] vs 8 [7.7%]; difference, -1.8% [95% CI, -9.7% to 6.1%]; odds ratio, 0.75 [95% CI, 0.25 to 2.24]; P = .78).

CONCLUSIONS AND RELEVANCE

Among patients with acute large vessel occlusion stroke, mechanical thrombectomy alone, compared with combined intravenous thrombolysis plus mechanical thrombectomy, failed to demonstrate noninferiority regarding favorable functional outcome. However, the wide confidence intervals around the effect estimate also did not allow a conclusion of inferiority.

TRIAL REGISTRATION

umin.ac.jp/ctr Identifier: UMIN000021488.

Mechanical Thrombectomy with the Novel NeVa M1 Stent Retriever: Do the Drop Zones Represent a Risk or a Benefit?

OBJECTIVE

The NeVa M1 thrombectomy device is a novel hybrid-cell stent retriever with multifunctional zones for optimized retrieval of resistant clots located in the M1 segment of the middle cerebral artery. The objective was to evaluate the safety and efficacy of the NeVa in a "real-life" setting.

METHODS

Twenty-nine consecutive patients (median age: 77 years) treated with the NeVa M1 for acute ischemic stroke of the M1 segement were retrospectively reviewed. First-pass and final modified thrombolysis in cerebral infarction (mTICI) scores, device-related complications, symptomatic intracranial hemorrhage, and 90-day modified Rankin scale (mRS) scores are reported. Primary outcome parameters were first-pass mTICI 2b-3 reperfusion and mRS 0-2 at 90 days.

RESULTS

Median National Institutes of Health Stroke Scale scores decreased from 16 to 12 after treatment. mTICI 2b-3 reperfusion rates were 55% after the first pass, 79% after 1-2 passes, and 100% after the final pass. mTICI 2c-3 was obtained in 48% after the first pass, 62% after 1-2 passes, and 72% after the final pass. Rescue treatment was performed in 4 patients (14%). Device-related complications included 1 asymptomatic caroticocavernous fistula, 1 asymptomatic M2 dissection, and 1 symptomatic intracranial hemorrhage. The procedure-related vasospasm rate was 48%. A 90-day mRS of 0-2 was achieved by 31%.

CONCLUSIONS

The NeVa M1 provides a high first-pass complete reperfusion rate with an adequate safety profile. To retrieve resistant clots, the stent design exerts high mechanical traction forces, which may trigger vasospasm and vessel wall damage. Large, comparative studies are warranted to draw a definite conclusion on this device.

Prediction of mTICI 3 recanalization and clinical outcomes in endovascular thrombectomy for acute ischemic stroke: a retrospective study in the Taiwan registry

PURPOSE

Early recanalization for acute ischemic stroke (AIS) due to large vessel occlusion (LVO) by endovascular thrombectomy (EVT) is strongly related to improved functional outcomes. With data obtained from the Taiwan registry, the factors associated with mTICI 3 recanalization and clinical outcomes in EVT are investigated.

METHODS

From January 2014 to September 2016, 108 patients who underwent EVT for AIS due to LVO in 11 medical centers throughout Taiwan were included. Complete recanalization is defined as achieving modified thrombolysis in cerebral infarction (mTICI) grade 3. Good clinical outcomes are defined by the modified Rankin scale (mRS) 0-2 at 3 months after EVT. Clinical and imaging parameters for predicting mTICI 3 recanalization and good clinical outcomes are analyzed.

RESULTS

Of the 108 patients who received EVT, 54 (50%) patients had mTICI 3 recanalization. Having received aspiration only and the use of IV-tPA are shown to be significant predictors for mTICI 3 recanalization with odds ratios of 2.61 and 2.53 respectively. Forty-six (42.6%) patients experienced good 3-month clinical outcomes (mRS 0-2). Pretreatment collateral statuses, NIHSS scores, time lapses between symptoms to needle, and the occurrence of hemorrhage at 24 h are all significant predictors for good outcomes with odds ratios of 2.88, 0.91, 0.99, and 0.31 respectively.

CONCLUSIONS

Prediction of mTICI 3 recanalization and clinical outcomes offer valuable clinical information for treatment planning in EVT.

Direct thrombectomy for stroke in the presence of absolute exclusion criteria for thrombolysis

BACKGROUND

Intravenous thrombolysis (IVT)-ineligible patients undergoing direct thrombectomy tended to have poorer functional outcome as compared with IVT-eligible patients undergoing bridging therapy. We aimed to assess radiological and functional outcomes in large vessel occlusion-related stroke patients receiving direct thrombectomy in the presence of absolute exclusion criteria for IVT vs relative exclusion criteria for IVT and vs non-exclusion criteria for IVT.

METHODS

A cohort study on prospectively collected data from 2282 patients enrolled in the Italian Registry of Endovascular Treatment in Acute Stroke cohort for treatment with direct thrombectomy (n = 486, absolute exclusion criteria for IVT alone; n = 384, absolute in combination with relative exclusion criteria for IVT; n = 777, relative exclusion criteria for IVT alone; n = 635, non-exclusion criteria for IVT).

RESULTS

After adjustment for unbalanced variables (model 1), ORs for 3-month death was higher in the presence of absolute exclusion criteria for IVT alone (vs relative exclusion criteria for IVT alone) (1.595, 95% CI 1.042-2.440) and in the presence of absolute exclusion criteria for IVT alone (vs non-exclusion criteria for IVT) (1.235, 95% CI 1.014-1.504). After adjustment for predefined variables (model 2: age, sex, pre-stroke mRS ≤ 1, NIHSS, occlusion in the anterior circulation, onset-to-groin time, and procedure time), ORs for 3-month death was higher in the presence of absolute exclusion criteria for IVT alone (vs relative exclusion criteria for IVT alone) (1.235, 95% CI 1.014-1.504) and in the presence of absolute exclusion criteria for IVT alone (vs non-exclusion criteria for IVT) (1.246, 95% CI 1.039-1.495). No significant difference was found between the groups as regards any type of intracerebral hemorrhage and parenchymal hematoma within 24 h, successful and complete recanalization after procedure, and modified Rankin Scale score 0-2 at 3 months. After adjustment for predefined variables of model 2, ORs for death were higher in the presence of recent administration of IV heparin (OR: 2.077), platelet count < 100,000/mm³ (OR: 4.798), bacterial endocarditis (OR: 15.069), neoplasm with increased hemorrhagic risk (OR: 6.046), and severe liver disease (OR: 6.124).

CONCLUSIONS

Radiological outcomes were similar after direct thrombectomy in patients with absolute, relative, and non- exclusion criteria for IVT, while an increase of fatal outcome was observed in the presence of some absolute exclusion criterion for IVT.

Outcomes of mechanical thrombectomy with pre-intravenous thrombolysis: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Whether pre-intravenous thrombolysis (IVT) provides any extra benefits to mechanical thrombectomy (MT) remains controversial. We conducted a systematic review and meta-analysis to compare MT with pre-IVT (IVT + MT) and MT without pre-IVT (MT) for acute ischemic stroke of large vessel occlusion.

METHODS

We systematically searched PubMed, EMBASE and Cochrane Library to identify studies comparing outcomes between IVT + MT and MT from inception to Jan 24, 2019. Random effects mode was used to pool relative risk (RR) with confidence intervals (CI) to compare functional independence in terms of modified Rankin Scale (mRS) 0-2, favorable outcome (mRS 0-1) and mortality at three-months, symptomatic intracerebral hemorrhage, successful reperfusion, and complete reperfusion between the two treatments groups.

RESULTS

We included 30 studies enrolling 8970 patients with acute ischemic stroke of large vessel occlusion. Compared with MT, IVT + MT significantly increased the rate of 3-month functional independence (RR 1.20, 95% CI 1.12-1.30;  P < 0.0001) and favorable outcome (RR 1.28; 95% CI 1.16-1.40; P < 0.0001), increased the rate of successful reperfusion (RR 1.04,95% CI 1.01-1.08;  P =  0.013) and complete reperfusion (RR 1.10; 95% CI 1.01-1.19; P = 0.024), reduced the rate of mortality (RR 0.74, 95% CI 0.67-0.82;  P < 0.0001), without significantly increasing the rate of symptomatic intracerebral hemorrhage (RR 0.98,95% CI 0.82-1.17;  P = 0.833). The results remained stable in sensitivity analyses and adjusting for publication bias.

CONCLUSIONS

Pre-IVT provides extra benefits to MT on clinical and imaging outcomes without increasing symptomatic intracerebral hemorrhage in acute ischemic stroke of large vessel occlusion.

Is intravenous thrombolysis still necessary in patients who undergo mechanical thrombectomy?

PURPOSE OF REVIEW

To summarize available evidence on the potential utility of pretreatment with intravenous thrombolysis (IVT) using recombinant tissue-plasminogen activator (rt-PA) in acute ischemic stroke (AIS) patients with large vessel occlusions (LVO) who are treated with mechanical thrombectomy.

RECENT FINDINGS

Despite theoretical concerns of a higher bleeding risk with IVT pretreatment, there are no data showing increased risk of symptomatic intracerebral hemorrhage (sICH) in patients with LVO receiving bridging therapy (IVT and mechanical thrombectomy) compared with direct mechanical thrombectomy (dMT). Additionally, evidence from observational studies suggest lower rates of infarctions in previously unaffected territories and higher rates of successful reperfusion, with lower number of device passes, in patients receiving bridging therapy. There are substantial discrepancies in studies comparing clinical outcomes between dMT and bridging therapy that are directly related to the inclusion of patients with contraindications to IVT in the dMT group. Ongoing clinical trials will provide definitive answers on the potential additional benefit of IVT in LVO patients receiving mechanical thrombectomy.

SUMMARY

IVT and mechanical thrombectomy are two effective reperfusion therapies that should be used in a swift and noncompeting fashion in AIS patients. AIS patients with LVO and no contraindications for IVT should receive promptly rt-PA bolus followed by immediate initiation of mechanical thrombectomy as indicated by current international recommendations, unless future randomized controlled trials provide evidence to proceed differently.

Comparative efficacy and safety of bridging strategies with direct mechanical thrombectomy in large vessel occlusion: A systematic review and meta-analysis

BACKGROUND

Whether bridging strategies[intravenous thrombolysis (IVT) + mechanical thrombectomy (MT)] are superior to mechanical thrombectomy alone for large vessel occlusion(LVO) is still uncertain. A systematic review and meta-analysis was conducted to investigate and evaluate comparative efficacy and safety of bridging strategies vs direct MT in patients with LVO.

METHODS

The PubMed, EMBASE and Cochrane library databases were searched to evaluate the efficacy and safety of bridging strategies with direct MT in LVO. Functional independence, mortality, symptomatic intracranial hemorrhage (sICH) and successful recanalization were assessed. The risk ratio (RR) and its 95% confidence interval (CI) were calculated.

RESULTS

The proportion of patients who received MT + IVT was significantly higher in functional independence and successful recanalization rate than MT alone patients. However, pooled results showed that the mortality of patients who received MT + IVT was significantly lower than that of MT alone patients. Moreover, no significant differences were observed in the incidence of sICH between the 2 groups.

CONCLUSION

The findings of our meta-analysis confirmed that bridging strategies improved functional outcomes, successful recanalization rate and reduced mortality rates. Moreover, the incidence of sICH showed no differences between the bridging strategies and MT alone treatments. However, the conduct of high-quality randomized clinical trials that directly compare both strategies is warranted.

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

BACKGROUND

Although endovascular treatment (EVT) is very effective for acute ischemia stroke (AIS) patients with proximal large vessels occlusion (LVO), whether bridging rPA before EVT in stroke patients of LVO is of any benefit and is currently one of the most urgent unanswered questions. We aim to comprehensively determine the efficacy and safety of direct EVT (DEVT) in AIS patients with LVO versus bridging therapy (BT).

METHODS

Clinical researches published in the Embase, PubMed, and Cochrane Library electronic databases up to May 2017 were identified for analysis. Two reviewers extracted data and conducted quality assessment independently. Statistical tests were performed to check for heterogeneity and publication bias. Subgroup and sensitivity analysis were also conducted to evaluate the robustness of the conclusions.

RESULTS

Overall, 13 studies involving 3302 patients met the inclusion criteria. The AIS patients with DEVT had a similar likelihood to achieve good functional outcome at 3 months (risk ratio [RR] = .93, 95% confidence interval [CI] = .85-1.01, P = .094), mortality at 3 months (RR = 1.10, 95% CI = .91-1.33, P = .33), and symptomatic intracranial hemorrhage (RR = 1.06, 95% CI = .74-1.51, P = .75) versus BT; furthermore, the risk of intracranial hemorrhage was lower in DEVT group (RR = .76, 95% CI = .60-.95, P = .02). No significant difference in recanalization rate existed between the 2 groups (RR = .97, 95% CI = .92-1.02, P = .22); however, in the subgroup analysis, it had a rise trend after DEVT than BT in IVT-eligible group (RR = 1.45, 95% CI = .95-2.22, P = .09).

CONCLUSIONS

DEVT appears to have equally effectiveness to BT with a low risk of intracranial hemorrhage in AIS patients with LVO, especially for anterior circulation, which offered a practical information to select appropriate therapeutic strategies for patients with LVO, though the level of evidence seems to be quite shaky.

Mechanical Thrombectomy Outcomes With or Without Intravenous Thrombolysis

Background and Purpose—

Intravenous thrombolysis (IVT) within 4.5 hours of symptom onset is currently recommended before mechanical thrombectomy (MT). We compared functional outcome, neurological recovery, reperfusion, and adverse events according to the use or not of IVT before MT.

Methods—

This is a post hoc analysis of the ASTER trial (Contact Aspiration Versus Stent Retriever for Successful Revascularization). The primary outcome was favorable 90-day functional outcome defined as a modified Rankin Scale of ≤2. Secondary outcomes were successful reperfusion following all procedures and after the first-line procedure, number of device passes, and change in National Institutes of Health Stroke Scale score at 24 hours. Safety outcomes included 90-day mortality and any symptomatic intracerebral hemorrhage.

Results—

Three hundred eighty-one patients were included, 250 of whom received IVT before MT (IVT+MT group). There were no significant differences between IVT+MT and MT-alone groups in 90-day favorable functional outcome, in successful reperfusion rate (modified Thrombolysis In Cerebral Infarction 2b or 3), in National Institutes of Health Stroke Scale score improvement at 24 hours, or in hemorrhagic complication rate. The 90-day mortality rate in the IVT+MT group was lower than after MT alone (fully-adjusted risk ratio, 0.59; 95% CI, 0.39–0.88). In a subgroup of patients without anticoagulant medication before stroke onset, we observed in the IVT+MT group a better functional outcome (fully-adjusted risk ratio, 1.38; 95% CI, 1.02–1.89), a higher successful recanalization rate after first-line strategy (fully-adjusted risk ratio, 1.26; 95% CI, 1.05–1.50), and a lower mortality rate (fully-adjusted risk ratio, 0.58; 95% CI, 0.36–0.93).

Conclusions—

Our results show that IVT+MT patients in the ASTER trial have lower 90-day mortality compared with those receiving MT alone. In a selected population of patients without prestroke anticoagulation, we demonstrated that IVT associated with MT might improve functional outcome and recanalization while reducing mortality rates.

Direct mechanical thrombectomy in tPA-ineligible and -eligible patients versus the bridging approach: a meta-analysis

Background

Whether pretreatment with intravenous thrombolysis prior to mechanical thrombectomy (IVT+MTE) adds additional benefit over direct mechanical thrombectomy (dMTE) in patients with large vessel occlusions (LVO) is a matter of debate.

Methods

This study-level meta-analysis was presented in accord with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Pooled effect sizes were calculated using the inverse variance heterogeneity model and displayed as summary Odds Ratio (sOR) and corresponding 95% confidence interval (95% CI). Sensitivity analysis was performed by distinguishing between studies including dMTE patients eligible for IVT (IVT-E) or ineligible for IVT (IVT-IN). Primary outcome measures were functional independence (modified Rankin Scale≤2) and mortality at day 90, successful reperfusion, and symptomatic intracerebral hemorrhage.

Results

Twenty studies, incorporating 5279 patients, were included. There was no evidence that rates of successful reperfusion differed in dMTE and IVT+MTE patients (sOR 0.93, 95% CI 0.68 to 1.28). In studies including IVT-IN dMTE patients, patients undergoing dMTE tended to have lower rates of functional independence and had higher odds for a fatal outcome as compared with IVT+MTE patients (sOR 0.78, 95% CI 0.61 to 1.01 and sOR 1.45, 95% CI 1.22 to 1.73). However, no such treatment group effect was found when analyses were confined to cohorts with a lower risk of selection bias (including IVT-E dMTE patients).

Conclusion

The quality of evidence regarding the relative merits of IVT+MTE versus dMTE is low. When considering studies with lower selection bias, the data suggest that dMTE may offer comparable safety and efficacy as compared with IVT+MTE. The conduct of randomized-controlled clinical trials seems justified.

Direct Mechanical Intervention Versus Bridging Therapy in Stroke Patients Eligible for Intravenous Thrombolysis: A Pooled Analysis of 2 Registries

BACKGROUND AND PURPOSE

Randomized controlled trials have shown that mechanical thrombectomy (MT) plus best medical treatment improves outcome in stroke patients with large-vessel occlusion in the anterior circulation. Whether direct MT is equally effective as bridging thrombolysis (intravenous thrombolysis plus MT) in intravenous thrombolysis eligible patients remains unclear.

METHODS

We compared clinical and radiological outcomes at 3 months in 249 bridging patients with 111 patients receiving direct MT for large-vessel occlusion anterior circulation stroke from 2 prospective registries (study period Essen: June 2012 to August 2013, Bern February 2009 to August 2014). We matched all patients from the direct MT group who would have qualified for intravenous thrombolysis with controls from the bridging group, using multivariate and propensity score methods. Subgroup analyses for internal carotid artery occlusions were performed.

RESULTS

Baseline characteristics did not differ between the direct MT group and bridging cohort, except for higher rates of coronary heart disease (P=0.029) and shorter intervals from onset to endovascular therapy (P<0.001) in the MT group. Functional outcome, mortality, and intracerebral hemorrhage did not differ, neither in univariate nor after multivariate and propensity score matching. However, in patients with internal carotid artery occlusion, mortality in the direct cohort was significantly lower.

CONCLUSIONS

In this matched-pair analysis, there was no difference in outcome in patients with large-vessel occlusion anterior circulation stroke treated with direct MT compared with those treated with bridging thrombolysis; however, mortality in patients with internal carotid artery occlusion treated with direct MT was significantly lower than after bridging thrombolysis. Randomized trials comparing direct MT with bridging therapy are needed.

Patient eligibility for thrombectomy after acute stroke: Northern French Alps database analysis

BACKGROUND

Since 2015, the emergence of mechanical thrombectomy as standard care in acute stroke has involved organizational changes not only for stroke centers, but also for entire emergency regional networks. The aim of our study was to assess the proportion of ischemic stroke patients, admitted to stroke units in the Northern French Alps within the first 6h of onset, eligible for thrombectomy.

METHODS

This study retrospectively analyzed the clinical and radiological data of all acute stroke patients hospitalized at three stroke units of the Northern French Alps Emergency Network (RENAU) in 2014. Eligible patients had proximal arterial occlusions of the anterior and posterior cerebral circulation, as confirmed by brain imaging, which could be treated by thrombectomy within 6h of symptom onset.

RESULTS

Of the 435 cases of acute ischemic stroke, 152 patients were treated by intravenous thrombolysis (IV rtPA). Of these patients, 83 (55%) had intracranial occlusions and were eligible for combined thrombectomy. Of the 283 patients not treatable by IV rtPA, 32 patients (11%) were eligible for primary thrombectomy.

CONCLUSION

Thrombectomy could be performed in 26% of our acute ischemic stroke patients (n=115/435), and a large increase in endovascular procedures is expected over the next few years that will require close collaboration among all partners in the emergency networks. Using our RENAU stroke database, it will be possible to compare various factors contributing to effective activity.

Towards personalised intra-arterial treatment of patients with acute ischaemic stroke: a study protocol for development and validation of a clinical decision aid

INTRODUCTION

Overall, intra-arterial treatment (IAT) proved to be beneficial in patients with acute ischaemic stroke due to a proximal occlusion in the anterior circulation. However, heterogeneity in treatment benefit may be relevant for personalised clinical decision-making. Our aim is to improve selection of patients for IAT by predicting individual treatment benefit or harm.

METHODS AND ANALYSIS

We will use data collected in the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN) trial to analyse the effect of baseline characteristics on outcome and treatment effect. A multivariable proportional odds model with interaction terms will be developed to predict the outcome for each individual patient, both with and without IAT. Model performance will be expressed as discrimination and calibration, after bootstrap resampling and shrinkage of regression coefficients, to correct for optimism. External validation will be conducted on data of patients in the Interventional Management of Stroke III trial (IMS III). Primary outcome will be the modified Rankin Scale (mRS) at 90 days after stroke.

ETHICS AND DISSEMINATION

The proposed study will provide an internationally applicable clinical decision aid for IAT. Findings will be disseminated widely through peer-reviewed publications, conference presentations and in an online web application tool. Formal ethical approval was not required as primary data were already collected.

TRIAL REGISTRATION NUMBERS

ISRCTN10888758; Post-results and NCT00359424; Post-resultsc.

Safety of endovascular treatment in acute stroke patients taking oral anticoagulants

Background

The endovascular treatment of acute cerebral ischemia has been proven beneficial without major safety concerns. To date, the role of endovascular treatment in patients treated with oral anticoagulants, which may be associated with periprocedural intracranial bleeding, remains uncertain.

Aims

The objective of the current analysis is to evaluate the safety of endovascular treatment in patients treated with oral anticoagulants.

Methods

The ENDOSTROKE-Registry is a commercially independent, prospective observational study in 12 stroke centers in Germany and Austria collecting pre-specified variables about endovascular stroke therapy.

Results

Data from 815 patients (median age 70 (interquartile range (IQR) 20), 57% male) undergoing endovascular treatment with known anticoagulation status were analyzed. A total of 85 (median age 76 (IQR 8), 52% male) patients (10.4%) took vitamin-K-antagonists prior to endovascular treatment. Anticoagulation status as measured with international normalized ratio was above 2.0 in 31 patients. Intracranial hemorrhage occurred in 11.8% of patients taking vitamin-K-antagonists compared to no-vitamin-K-antagonists (12.2%, p = 0.909). After adjustment for confounding factors which were unbalanced at univariate level such as NIHSS and age, anticoagulation status was not found to significantly influence clinical outcome (modified Rankin Scale 3–6) and occurrence of intracranial hemorrhage in a multivariate logistic regression analysis.

Conclusion

Prior use of vitamin-K-antagonists was not associated with a higher rate of periprocedural intracranial hemorrhage after endovascular treatment or worse outcome. Endovascular treatment should be considered as an important treatment option in patients taking vitamin-K-antagonists.