Successful mechanical thrombectomy in acute ischemic stroke: revascularization grade and functional independence

Most studies define the technical success of endovascular thrombectomy (EVT) as a Thrombolysis in Cerebral Infarction (TICI) revascularization grade of 2b or higher. However, growing evidence suggests that TICI 3 is the best angiographic predictor of improved functional outcomes. To assess the association between successful TICI revascularization grades and functional independence at 90 days, we performed a systematic review and network meta-analysis of thrombectomy studies that reported TICI scores and functional outcomes, measured by the modified Rankin Scale, using the semi-automated AutoLit software platform. Forty studies with 8691 patients were included in the quantitative synthesis. Across TICI, modified TICI (mTICI), and expanded TICI (eTICI), the highest rate of good functional outcomes was observed in patients with TICI 3 recanalization, followed by those with TICI 2c and TICI 2b recanalization, respectively. Rates of good functional outcomes were similar among patients with either TICI 2c or TICI 3 grades. On further sensitivity analysis of the eTICI scale, the rates of good functional outcomes were equivalent between eTICI 2b50 and eTICI 2b67 (OR 0.81, 95% CI 0.52 to 1.25). We conclude that near complete or complete revascularization (TICI 2c/3) is associated with higher rates of functional outcomes after EVT.

Association between CHADS2, CHA2DS2-VASc, ATRIA, and Essen Stroke Risk Scores and Unsuccessful Recanalization after Endovascular Thrombectomy in Acute Ischemic Stroke Patients

Background: The CHADS2, CHA2DS2-VASc, ATRIA, and Essen scores have been developed for predicting vascular outcomes in stroke patients. We investigated the association between these stroke risk scores and unsuccessful recanalization after endovascular thrombectomy (EVT). Methods: From the nationwide multicenter registry (Selection Criteria in Endovascular Thrombectomy and Thrombolytic therapy (SECRET)) (Clinicaltrials.gov NCT02964052), we consecutively included 501 patients who underwent EVT. We identified pre-admission stroke risk scores in each included patient. Results: Among 501 patients who underwent EVT, 410 (81.8%) patients achieved successful recanalization (mTICI ≥ 2b). Adjusting for body mass index and p < 0.1 in univariable analysis revealed the association between all stroke risk scores and unsuccessful recanalization (CHADS2 score: odds ratio (OR) 1.551, 95% confidence interval (CI) 1.198–2.009, p = 0.001; CHA2DS2VASc score: OR 1.269, 95% CI 1.080–1.492, p = 0.004; ATRIA score: OR 1.089, 95% CI 1.011–1.174, p = 0.024; and Essen score: OR 1.469, 95% CI 1.167–1.849, p = 0.001). The CHADS2 score had the highest AUC value and differed significantly only from the Essen score (AUC of CHADS2 score; 0.618, 95% CI 0.554–0.681). Conclusion: All stroke risk scores were associated with unsuccessful recanalization after EVT. Our study suggests that these stroke risk scores could be used to predict recanalization in stroke patients undergoing EVT.

Quality improvement project to improve patient outcomes by reducing door to CT and door to needle time and increasing appropriate referrals for endovascular thrombectomy.

This paper describes a stroke quality improvement (QI) project in a primary stroke centre in a 431-bed hospital serving a local population of 114 000 people. Approximately 170 acute strokes are treated each year in a seven-bed stroke unit managed by three geriatricians with a subspecialty interest in stroke. 24-hour CT radiology service is available. Endovascular thrombectomy (EVT) is performed by neuro-interventional radiology at one of two comprehensive stroke centres located 90–120 min away.In 2018, as part of a national collaborative QI initiative a new national thrombectomy referral pathway was introduced with an aim that all eligible patients be referred for EVT. This initiative included maximising timely access to CT and thrombolysis. Review of local data highlighted significant deficits in these areas.A local QI team convened and a multidisciplinary approach was employed to map the existing process for CT access and time to thrombolysis decision.We describe how focused timesaving interventions such as; new emergency and radiology department ‘pre-alerts’, dedicated acute stroke pagers, new ‘FAST’ registration by clerical staff, new CT ordering codes and new ‘FAST packs’ (including tissue plasminogen activator, paper National Institute of Health Stroke Scale scoring tools, consent forms and EVT patient selection tools) were created and incorporated into a multidisciplinary detailed clinical stroke care pathway.We describe how we achieved our SMART aims; to reduce our door to CT time and to reduce our door to needle time to the national target of less than 30 min. A third aim was to increase the number of patients referred for EVT from our centre.This project is an accurate description of how a multidisciplinary approach combined with teamwork and effective communication can create sustainable improved patient care and is generalisable to all institutions that require timely referral to external centres for EVT.

Predictors of 30-day mortality after endovascular thrombectomy for large vessel occlusion in the elderly

Objectives Elderly acute ischemic stroke (AIS) patients (≥80 years) would have dismal clinical outcomes even after successful endovascular revascularization for large vessel occlusion (LVO) in the anterior circulation. We aimed to identify predictors of 30-day mortality after endovascular thrombectomy (EVT) in the elderly. Materials and Methods We included older patients who underwent EVT for AIS due to LVO within 6 h after stroke onset in the anterior circulation between 2017 and 2019. Patients due to posterior circulation stroke, with intracerebral hemorrhage (ICH) or pre-stroke modified Rankin Scale (mRS) score of 4 and 5 were excluded. The primary outcome was mortality within 30 days of EVT. The association between clinical, imaging, procedural, follow-up imaging and mortality were analyzed. Successful reperfusion was defined as modified Thrombolysis in Cerebral Infarction (mTICI) score of 2b or 3. Possible predictors of 30-day mortality were assessed by univariate and multivariable logistic regression. Results Total 238 AIS patients eligible for EVT were identified with 58 patients aged 80 years or more. 48 patients met inclusion criteria. Median age was 86 years (age range, 82–102 years). Successful reperfusion was achieved in 38 (79.2%) patients. The 30-day and 90-day mortality rate were 25% and 33.3%, respectively. The independent predictors of 30-day mortality were collateral scores <3 on mCTA (adjusted OR, 16.571; 95% CI, 1.041–263.868; p = 0.047) and number of passes (adjusted OR, 2.475; 95% CI, 1.047–5.847; p = 0.039). Conclusions Lower collateral scores on mCTA and higher number of passes in thrombectomy were independently predictive of 30-day mortality in the elderly.

Mobile stroke care expedites intravenous thrombolysis and endovascular thrombectomy

BackgroundThe number of mobile stroke programmes has increased with evidence, showing they expedite intravenous thrombolysis. Outstanding questions include whether time savings extend to patients eligible for endovascular therapy and impact clinical outcomes.ObjectiveOur mobile stroke unit (MSU), based at an academic medical centre in upstate New York, launched in October 2018. We reviewed prospective observational data sets over 26 months to identify MSU and non-MSU emergency medical service (EMS) patients who underwent intravenous thrombolysis or endovascular thrombectomy for comparison of angiographic and clinical outcomes.ResultsOver 568 days in service, the MSU was dispatched 1489 times (2.6/day) and transported 300 patients (20% of dispatches). Intravenous tissue plasminogen activator (tPA) was administered to 57 MSU patients and the average time from 911 call-to-tPA was 42.5 min (±9.2), while EMS transported 73 patients who received tPA at 99.4 min (±35.7) (p<0.001). Seven MSU patients (12%) received tPA from 3.5 hours to 4.5 hours since last known well and would likely have been outside the window with EMS care. Endovascular thrombectomy was performed on 21 MSU patients with an average 911 call-to-groin puncture time of 99.9 min (±18.1), while EMS transported 54 patients who underwent endovascular thrombectomy (ET) at 133.0 min (±37.0) (p=0.0002). There was no difference between MSU and traditional EMS in modified Rankin score at 90-day clinic follow-up for patients undergoing intravenous thrombolysis or endovascular thrombectomy, whether assessed as a dichotomous or ordinal variable.ConclusionsMobile stroke care expedited both intravenous thrombolysis and endovascular thrombectomy. There is an ongoing need to show improved functional outcomes with MSU care.

Effect of Occlusion Site on the Safety and Efficacy of Intravenous Alteplase Before Endovascular Thrombectomy: A Prespecified Subgroup Analysis of DIRECT-MT

Background and Purpose: Recent trials showed thrombectomy alone was comparable to bridging therapy in patients with anterior circulation large vessel occlusion eligible for both intravenous alteplase and endovascular thrombectomy. We performed this study to examine whether occlusion site modifies the effect of intravenous alteplase before thrombectomy. Methods: This is a prespecified subgroup analysis of a randomized trial evaluating risk and benefit of intravenous alteplase before thrombectomy (DIRECT-MT [Direct Intra-Arterial Thrombectomy in Order to Revascularize AIS Patients With Large Vessel Occlusion Efficiently in Chinese Tertiary Hospitals]). Among 658 randomized patients, 640 with baseline occlusion site information were included. The primary outcome was the score on the modified Rankin Scale at 90 days. Multivariable ordinal logistic regression analysis with an interaction term was used to estimate treatment effect modification by occlusion location (internal carotid artery versus M1 versus M2). We report the adjusted common odds ratio for a shift toward better outcome on the modified Rankin Scale after thrombectomy alone compared with combination treatment adjusted for age, the National Institutes of Health Stroke Scale score at baseline, the time from stroke onset to randomization, the modified Rankin Scale score before stroke onset, and collateral score per the DIRECT-MT statistical analysis plan. Results: The overall adjusted common odds ratio was 1.08 (95% CI, 0.82–1.43) with thrombectomy alone compared with combination treatment, and there was no significant treatment-by-occlusion site interaction ( P =0.47). In subgroups based on occlusion location, we found the following adjusted common odds ratios: 0.99 (95% CI, 0.62–1.59) for internal carotid artery occlusions, 1.12 (95% CI, 0.77–1.64) for M1 occlusions, and 1.22 (95% CI, 0.53–2.79) for M2 occlusions. No treatment-by-occlusion site interactions were observed for dichotomized modified Rankin Scale distributions and successful reperfusion (extended thrombolysis in Cerebral Infarction score ≥2b) before thrombectomy. Differences in symptomatic hemorrhage rate were not significant between occlusion locations (internal carotid artery occlusion: 7.02% in bridging therapy versus 7.14% for thrombectomy alone, P =0.97; M1 occlusion: 5.06% versus 2.48%, P =0.22; M2 occlusion: 9.09% versus 4.76%; P =0.78). Conclusions: In this prespecified subgroup of a randomized trial, we found no evidence that occlusion location can inform intravenous alteplase decisions in endovascular treatment eligible patients directly presenting at endovascular treatment capable centers. Future studies are needed to confirm our findings. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03469206.

Posterior Circulation Endovascular Thrombectomy for Large Vessels Occlusion in Patients Presenting with NIHSS Score ≤ 10

Mechanical thrombectomy (MT) is currently the gold standard treatment for ischemic stroke due to large vessel occlusion (LVO). However, the evidence of clinical usefulness of MT in posterior circulation LVO (pc-LVO) is still doubtful compared to the anterior circulation, especially in patients with mild neurological symptoms. The database of 10 high-volume stroke centers in Europe, including a period of three year and a half, was screened for patients with an acute basilar artery occlusion or a single dominant vertebral artery occlusion (“functional” BAO) presenting with a NIHSS ≤10, and with at least 3 months follow-up. A total of 63 patients were included. Multivariate analysis demonstrated that female gender (adjusted OR 0.04; 95% CI 0–0.84; p = 0.04) and combined technique (adj OR 0.001; 95% CI 0–0.81; p = 0.04) were predictors of worse outcome. Higher pc-ASPECTS (adj OR 4.75; 95% CI 1.33–16.94; p = 0.02) and higher Delta NIHSS (adj OR 2.06; 95% CI 1.16–3.65; p = 0.01) were predictors of better outcome. Delta NIHSS was the main predictor of good outcome at 90 days in patients with posterior circulation LVO presenting with NIHSS score ≤ 10.