Correlation of AOL recanalization, TIMI reperfusion and TICI reperfusion with infarct growth and clinical outcome

Whether mTICI 3 or mTICI 2b is better in patients with vertebrobasilar artery occlusion undergoing endovascular treatment depends on pc-ASPECTS

BACKGROUND

The clinical relevance of differentiating between mTICI (modified Thrombolysis In Cerebral Infarction) 2b and mTICI 3 in patients with vertebrobasilar artery occlusion (VBAO) remains unclear. This study aimed to investigate whether mTICI 3 improves functional outcomes compared with mTICI 2b in patients with VBAO and whether this improvement differs according to extent of ischemic damage.

METHODS

This retrospective study enrolled patients with VBAO within 24 hours of the estimated occlusion time at 65 stroke centers in a nationwide registration in China. The primary outcome was favorable functional outcome (modified Rankin scale score 0-3) at 90 days. Patients were matched by final mTICI grade using propensity score matching (PSM) and inverse probability of treatment weighting (IPTW). Logistic regression and ordinal regression models were used to assess the impact of mTICI 2b versus mTICI 3 grading on prognosis, based on different extent of ischemia damage (posterior circulation Alberta Stroke Program Early CT Score-pc-ASPECTS of 9-10, 7-8, and 3-6) and treatment strategies (bridging therapy and direct endovascular therapy (EVT)).

RESULTS

A total of 2075 patients with VBAO and successful reperfusion were included, 652 patients (31.4%) achieved mTICI 2b and 1423 patients (68.6%) achieved mTICI 3. After adjustment for confounders, achieving mTICI 3 following EVT in patients with VBAO and pc-ASPECTS 9-10 (OR 1.54, 95% CI 1.16 to 2.03) and pc-ASPECTS 7-8 (OR 1.80, 95% CI (1.26 to 2.56) were associated with favorable functional outcome compared with mTICI 2b, especially in those receiving direct EVT. However, in patients with pc-ASPECTS≤6, functional outcomes at 90 days did not differ between mTICI 3 and mTICI 2b (OR 1.12, 95% CI 0.67 to 1.88), irrespective of using bridging therapy or direct EVT.

CONCLUSION

In patients with VBAO undergoing EVT with pc-ASPECTS>6, achieving mTICI 3 favors better outcomes compared with mTICI 2b, especially in those receiving direct EVT. However, in patients with pc-ASPECTS≤6, mTICI 3 did not improve functional outcomes compared with mTICI 2b. Interventionalists should carefully assess the risk-benefit of additional maneuvers once mTICI 2b reperfusion is restored in EVT for patients with VBAO and pc-ASPECTS≤6. Further studies are needed to guide treatment decisions in these cases.

Mediation Analysis of Acute Carotid Stenting in Tandem Lesions: Effect on Functional Outcome in a Multicenter Registry

BACKGROUND AND OBJECTIVES

Current evidence suggests that acute carotid artery stenting (CAS) for cervical lesions is associated with better functional outcomes in patients with acute stroke with tandem lesions (TLs) treated with endovascular therapy (EVT). However, the underlying causal pathophysiologic mechanism of this relationship compared with a non-CAS strategy remains unclear. We aimed to determine whether, and to what degree, reperfusion mediates the relationship between acute CAS and functional outcome in patients with TLs.

METHODS

This subanalysis stems from a multicenter retrospective cohort study across 16 stroke centers from January 2015 to December 2020. Patients with anterior circulation TLs who underwent EVT were included. Successful reperfusion was defined as a modified Thrombolysis in Cerebral Infarction scale ≥2B by the local team at each participating center. Mediation analysis was conducted to examine the potential causal pathway in which the relationship between acute CAS and functional outcome (90-day modified Rankin Scale) is mediated by successful reperfusion.

RESULTS

A total of 570 patients were included, with a median age (interquartile range) of 68 (59-76), among whom 180 (31.6%) were female. Among these patients, 354 (62.1%) underwent acute CAS and 244 (47.4%) had a favorable functional outcome. The remaining 216 (37.9%) patients were in the non-CAS group. The CAS group had significantly higher rates of successful reperfusion (91.2% vs 85.1%; p = 0.025) and favorable functional outcomes (52% vs 29%; p = 0.003) compared with the non-CAS group. Successful reperfusion was a strong predictor of functional outcome (adjusted common odds ratio [acOR] 4.88; 95% CI 2.91-8.17; p < 0.001). Successful reperfusion partially mediated the relationship between acute CAS and functional outcome, as acute CAS remained significantly associated with functional outcome after adjustment for successful reperfusion (acOR 1.89; 95% CI 1.27-2.83; p = 0.002). Successful reperfusion explained 25% (95% CI 3%-67%) of the relationship between acute CAS and functional outcome.

DISCUSSION

In patients with TL undergoing EVT, successful reperfusion predicted favorable functional outcomes when CAS was performed compared with non-CAS. A considerable proportion (25%) of the treatment effect of acute CAS on functional outcome was found to be mediated by improvement of successful reperfusion rates.

Reliability assessment of distal occlusion eTICI scoring

BACKGROUND

The eThrombolysis in Cerebral Infarction (eTICI) score has been validated in proximal large artery occlusion (pLAOs). Despite the growing number of distal medium vessel occlusions (DMVOs) mechanical thrombectomies (MT) and the widespread utilization of the eTICI scoring system, its reliability and standardization for more distal occlusions have not been validated. We aim to evaluate the interrater reliability of eTICI scores in primary DMVOs.

METHODS

This was a retrospective analysis of a prospectively maintained database for consecutive patients with pLAO and DMVO MT at a single comprehensive stroke center from 2015 to 2022. Two fellowship-trained neurointerventionalists blindly/independently assessed digital subtraction angiograms for final eTICI, followed by consensus reads for discrepancies.

RESULTS

59 DMVO of 2248 thrombectomies [M3:29(50%)/M4:1(2%)/A1:3(5%)/A2:12(22%)/A3: 5(9%)/P1:7(12%)/P2:1(2%)] and 124 pLAOs of 308 thrombectomies [i-ICA:13(11%)/MCA-M1: 111(90%)] were included. The distribution of final eTICI scores was comparable between pLAO vs DMVOs (p = 0.82). The pLAO final eTICI score assessment between two readers demonstrated moderate reliability with a kappa0.77 (95%CI: 0.67-0.88), while the DMVO eTICI score assessment exhibited almost-perfect agreement with kappa 0.94 (95%CI: 0.90-0.99). The agreement between the consensus read and the original report in DMVOs was 0.86 (95% CI: 0.71-1.00) while for pLAO it was 0.83(95% CI: 0.76-0.90). The performance of eTICI was comparable amongst different DMVO territories as well as for distal vs. very distal occlusions.

CONCLUSION

eTICI score exhibited comparable performance for DMVO as compared to pLAO strokes. Further studies investigating DMVO eTICI grading and clinical outcomes are warranted.

Influencing factors of futile recanalization after endovascular intervention in patients with acute basilar artery occlusion

OBJECTIVES

To explore the influence factors for futile recanalization following endovascular treatment (EVT) in patients with acute basilar artery occlusion (BAO).

METHODS

Clinical data of patients with acute BAO, who underwent endovascular treatment within 24 h of onset from January 2017 to November 2022, were retrospectively analyzed. The futile recanalization was defined as modified thrombolysis in cerebral infarction (mTICI) grade ≥2b or 3 after successful reperfusion, but the modified Rankin Scale score >2 at 3 months after EVT. Binary logistic regression model was used to analyze the influencing factors of futile recanalization.

RESULTS

A total of 471 patients with a median age of 68 (57, 74) years were included and 68.9% were males, among whom 298 (63.27%) experienced futile recanalization. Multivariate analysis revealed that concomitant atrial fibrillation (OR=0.456, 95%CI: 0.282-0.737, P<0.01), bridging thrombolysis (OR=0.640, 95%CI: 0.416-0.985, P<0.05), achieving mTICI grade 3 (OR=0.554, 95%CI: 0.334-0.918, P<0.05), arterial occlusive lesion (AOL) grade 3 (OR=0.521, 95%CI: 0.326-0.834, P<0.01), and early postoperative statin therapy (OR=0.509, 95%CI: 0.273-0.948, P<0.05) were protective factors for futile recanalization after EVT in acute BAO patients. High baseline National Institutes of Health Stroke Scale (NIHSS) score (OR=1.068, 95%CI: 1.049-1.087, P<0.01), coexisting hypertension (OR=1.571, 95%CI: 1.017-2.427, P<0.05), multiple retrieval attempts (OR=1.237, 95%CI: 1.029-1.488, P<0.05) and postoperative hemorrhagic transformation (OR=8.497, 95%CI: 2.879-25.076, P<0.01) were risk factors. For trial of ORG 10172 in acute stroke treatment (TOAST) classification, cardiogenic embolism (OR=0.321, 95%CI: 0.193-0.534, P<0.01) and other types (OR=0.499, 95%CI: 0.260-0.961, P<0.05) were related to lower incidence of futile recanalization.

CONCLUSIONS

The incidence of futile recanalization after EVT in patients with acute BAO is high. Bridging venous thrombolysis before operation and an early postoperative statin therapy may reduce the incidence of futile recanalization.

Predicting outcome in acute stroke with large vessel occlusion-application and validation of MR PREDICTS in the ESCAPE-NA1 population

BACKGROUND

Predicting outcome after endovascular treatment for acute ischemic stroke is challenging. We aim to investigate differences between predicted and observed outcomes in patients with acute ischemic stroke treated with endovascular treatment and to evaluate the performance of a validated outcome prediction score.

PATIENTS AND METHODS

MR PREDICTS is an outcome prediction tool based on a logistic regression model designed to predict the treatment benefit of endovascular treatment based on the MR CLEAN and HERMES populations. ESCAPE-NA1 is a randomized trial of nerinetide vs. placebo in patients with acute stroke and large vessel occlusion. We applied MR PREDICTS to patients in the control arm of ESCAPE-NA1. Model performance was assessed by calculating its discriminative ability and calibration.

RESULTS

Overall, 556/1105 patients (50.3%) in the ESCAPE-NA1-trial were randomized to the control arm, 435/556 (78.2%) were treated within 6 h of symptom onset. Good outcome (modified Rankin scale 0-2) at 3 months was achieved in 275/435 patients (63.2%), the predicted probability of good outcome was 52.5%. Baseline characteristics were similar in the study and model derivation cohort except for age (ESCAPE-NA1: mean: 70 y vs. HERMES: 66 y), hypertension (72% vs. 57%), and collaterals (good collaterals, 15% vs. 44%). Compared to HERMES we observed higher rates of successful reperfusion (TICI 2b-3, ESCAPE-NA1: 87% vs. HERMES: 71%) and faster times from symptom onset to reperfusion (median: 201 min vs. 286 min). Model performance was good, indicated by a c-statistic of 0.76 (95%confidence interval: 0.71-0.81).

CONCLUSION

Outcome-prediction using models created from HERMES data, based on information available in the emergency department underestimated the actual outcome in patients with acute ischemic stroke and large vessel occlusion receiving endovascular treatment despite overall good model performance, which might be explained by differences in quality of and time to reperfusion. These findings underline the importance of timely and successful reperfusion for functional outcomes in acute stroke patients.

Pooled blood volume measured by final flat-panel detector computed tomography predicts outcome after endovascular thrombectomy for acute ischemic stroke

Background

Pooled blood volume (PBV), measured in real-time in the angiography room using an angiography system, correlates with cerebral blood volume (CBV). We examined the usefulness of PBV in endovascular thrombectomy (EVT) for acute ischemic stroke (AIS).

Methods

EVT for AIS in the anterior circulation (internal carotid artery (ICA) and middle cerebral artery (MCA)) was performed in 31 cases (13 males, 18 females, average age 75.7 years). PBV was acquired using a biplane flat-panel detector (FD) angiographic system. Then, we measured the average PBV value in the M1-6 regions similar to the Alberta Stroke Program Early CT score (ASPECTS) before and after EVT. We investigated factors associated with favorable outcome at 90 days after EVT.

Results

There were 13 patients (41.9%) in the good outcome group (mRS (modified Rankin Scale) ≦2) and 18 patients (58.1%) in the poor outcome group (mRS>2). In univariate analysis, NIHSS (National Institutes of Health Stroke Scale) (odds ratio [OR] 0.74, 95% CI 0.57-0.87, p < 0.0001) and post PBV value (odds ratio [OR] 1.13, 95% CI 1.03-1.29, p = 0.0086) were significantly associated with good outcome. The good outcome group had significantly higher post-thrombectomy PBV value (3.69 ± 0.32 ml/100 g versus 2.78 ± 0.93 ml/100 g, P = 0.002) compared to that of the poor outcome group. The relationship between pre-thrombectomy PBV value and outcome at 90 days was not significant.

Conclusions

Post-operative PBV value measured by FD-CT (computed tomography) correlated with 90-day outcome after EVT for AIS. FD-CT-PBV would be one of the good predictors of clinical outcome.

Intraarterial thrombolytics as an adjunct to mechanical thrombectomy in patients with basilar artery occlusion

BACKGROUND AND PURPOSE

There are limited data regarding safety and effectiveness of concurrent intraarterial thrombolytics as adjunct to mechanical thrombectomy in acute ischemic stroke patients with basilar artery occlusion.

METHODS

We analyzed data from a prospective multicenter registry to assess the independent effect of intraarterial thrombolysis on (1) favorable outcome (modified Rankin Scale 0-3) at 90 days; (2) symptomatic intracranial hemorrhage (sICH) within 72 hours; and (3) death within 90 days post-enrollment after adjustment for potential confounders.

RESULTS

There was no difference in the adjusted odds of achieving favorable outcome at 90 days (odds ratio [OR] = 1.1, 95% confidence interval [CI]: 0.73-1.68) in patients who received intraarterial thrombolysis (n = 126) compared with those who did not receive intraarterial thrombolysis (n = 1546) despite significantly higher use in patients with postprocedure modified Thrombolysis in Cerebral Infarction (mTICI) grade <3. There were no differences in adjusted odds of sICH within 72 hours (OR = 0.8, 95% CI: 0.31-2.08) or death within 90 days (OR = 0.91, 95% CI: 0.60-1.37). In subgroup analyses, intraarterial thrombolysis was associated with (nonsignificantly) higher odds of achieving a favorable outcome at 90 days among patients aged between 65 and 80 years, those with National Institutes of Health Stroke Scale score <10, and those with postprocedure mTICI grade 2b.

CONCLUSIONS

Our analysis supported the safety of intraarterial thrombolysis as adjunct to mechanical thrombectomy in acute ischemic stroke patients with basilar artery occlusion. Identification of patient subgroups in whom intraarterial thrombolytics appeared to be more beneficial may assist in future clinical trial designs.

Imaging of Central Nervous System Ischemia

OBJECTIVE

This article describes imaging modalities used in the evaluation of patients presenting with symptoms of acute ischemic stroke.

LATEST DEVELOPMENTS

The year 2015 marked the beginning of a new era in acute stroke care with the widespread adoption of mechanical thrombectomy. Subsequent randomized controlled trials in 2017 and 2018 brought the stroke community even further into this new territory with the expansion of the eligibility window for thrombectomy using imaging-based patient selection, which led to an increase in the use of perfusion imaging. Now, after several years of routine use, the debate is ongoing as to when this additional imaging is truly required and when it results in unnecessary delays in time-sensitive stroke care. At this time, more than ever, a robust understanding of neuroimaging techniques, applications, and interpretation is essential for the practicing neurologist.

ESSENTIAL POINTS

CT-based imaging is the first step in most centers for the evaluation of patients presenting with symptoms of acute stroke because of its wide availability, speed, and safety. Noncontrast head CT alone is sufficient for IV thrombolysis decision making. CT angiography is very sensitive for the detection of large-vessel occlusion and can be used reliably to make this determination. Advanced imaging including multiphase CT angiography, CT perfusion, MRI, and MR perfusion can provide additional information useful for therapeutic decision making in specific clinical scenarios. In all cases, it is essential that neuroimaging be performed and interpreted rapidly to allow for timely reperfusion therapy.

The safety and efficacy of periprocedural intravenous anticoagulants for acute ischemic stroke patients who underwent endovascular treatment: Sub-analysis of the RESCUE-Japan Registry 2

The efficacy and safety of periprocedural anticoagulant therapy are still controversial. We investigated the effects of periprocedural anticoagulation on patients who underwent endovascular therapy (EVT) for acute ischemic stroke (AIS). The patients were dichotomized into two groups according to the use of intravenous anticoagulant during or within 24 h after EVT (AC or non-AC group). Primary outcome was defined as a modified Rankin Scale (mRS) score of 0-2 at 90 days. Safety outcomes were defined as any or symptomatic intracerebral hemorrhages (ICH). Among 1278 enrolled patients, 740 patients (57.9%) were in the AC group and the remaining 538 patients (42.1%) were in the non-AC group. The median dose of heparin was 5000 units intraoperatively, and 10,000 units /day postoperatively. In the AC group, hypercholesterolemia, higher pre-stroke modified Rankin Scale score, non-cardiac embolism etiology, higher rate of anticoagulant premedication, non-administration of t-PA (tissue plasminogen activator), later admission, and longer procedure time were observed. The rate of primary outcomes was not significantly different between the AC and non-AC groups (40.1% vs. 43.9%; adjusted odds ratio, 1.29; 95% CI, 0.96-1.73; p = 0.09). The incidence of any (26.2% vs. 25.7%; p = 0.80; adjusted odds ratio, 0.97; 95% CI, 0.72-1.22) and symptomatic (4.3% vs. 5.0%; p = 0.52; adjusted OR, 0.83; 95% CI, 0.46-1.51) intracranial hemorrhage within 72 h were not significantly different between the groups. Periprocedural anticoagulant therapy after acute revascularization did not relate to prognosis and intracranial hemorrhage after EVT.

Risk factors of late lesion growth after acute ischemic stroke treatment

Background

Even days after treatment of acute ischemic stroke due to a large vessel occlusion, the infarct lesion continues to grow. This late, subacute growth is associated with unfavorable functional outcome. In this study, we aim to identify patient characteristics that are risk factors of late, subacute lesion growth.

Methods

Patients from the MR CLEAN trial cohort with good quality 24 h and 1-week follow up non-contrast CT scans were included. Late Lesion growth was defined as the difference between the ischemic lesion volume assessed after 1-week and 24-h. To identify risk factors, patient characteristics associated with lesion growth (categorized in quartiles) in univariable ordinal analysis (p < 0.1) were included in a multivariable ordinal regression model.

Results

In the 226 patients that were included, the median lesion growth was 22 (IQR 10–45) ml. In the multivariable model, lower collateral capacity [aOR: 0.62 (95% CI: 0.44–0.87); p = 0.01], longer time to treatment [aOR: 1.04 (1–1.08); p = 0.04], unsuccessful recanalization [aOR: 0.57 (95% CI: 0.34–0.97); p = 0.04], and larger midline shift [aOR: 1.18 (95% CI: 1.02–1.36); p = 0.02] were associated with late lesion growth.

Conclusion

Late, subacute, lesion growth occurring between 1 day and 1 week after ischemic stroke treatment is influenced by lower collateral capacity, longer time to treatment, unsuccessful recanalization, and larger midline shift. Notably, these risk factors are similar to the risk factors of acute lesion growth, suggesting that understanding and minimizing the effects of the predictors for late lesion growth could be beneficial to mitigate the effects of ischemia.

Clinical effect of successful reperfusion in patients presenting with NIHSS < 6 and large vessel occlusion

PURPOSE

The purpose of this study was to evaluate the impact of reperfusion in patients with large vessel occlusion (LVO) of the anterior circulation and National Institutes of Health Stroke Scale (NIHSS)< 6.

METHODS

It was a retrospective cohort study. The reperfusion grade was determined using the modified thrombolysis in cerebral infarction (TICI) score. The modified Rankin Score (mRS) ≤1 were defined as excellent and (mRS) ≤2 as favorable outcome at 3-month. Meanwhile, the all-cause mortality, intracerebral hemorrhage, and complications were recorded. Multivariate logistic regression analyses were performed to evaluate outcomes.

RESULTS

Seventy-six patients (86.4%) achieved reperfusion (TICI2B/3). Excellent outcome was achieved in 62 (70.5%) and favorable outcome in 69 (78.4%). All-cause death occurred in 2 (2.3%). The rate of excellent outcome in patients with TICI0,1,2A was 41.7%, with TICI2B 69.2%, and with TICI3 78.0% (p < 0.05). In a multivariate logistic regression analysis related to excellent outcome, the OR(95% CI) was 5.68(1.35,23.95) for TICI3; the test for linear trend by entering categorical variables as continuous variables in the adjusted model (p for trend=0.02<0.05), defining TICI0,1,2A as reference. Subgroup analyses showed without intravenous thrombolysis (IVT) (OR, 14.29; 95% CI, 1.76-116.37) and with middle cerebral artery (MCA) occlusion (OR, 7.97; 95% CI,1.26-50.32), the excellent outcome further improved with TICI3. Findings were similar in favorable outcome.

CONCLUSIONS

Our results indicated that successful reperfusion was intensely connected with better functional outcomes for patients with LVO presenting with NIHSS<6 in the anterior circulation, especially MCA occlusion and pretreatment without IVT.

Influence of single pass recanalization in acute ischemic stroke with large vessel occlusion in patients of Asian ethnicity

BACKGROUND AND PURPOSE

A previous report revealed single pass recanalization was associated with better functional outcome for patients with acute ischemic stroke with large vessel occlusion in real-world settings. However, the effect of single pass recanalization in acute large vessel occlusion based on the largest registry in real-world settings in Asian population are not well scrutinized.

MATERIALS AND METHODS

RESCUE-Japan Registry-2 was a physician-initiated prospective multicenter registry that enrolled consecutive patients with acute large vessel occlusion who were admitted within 24 h of onset. We compared patients who underwent endovascular therapy and achieved good recanalization in single or multiple device passes (single-pass group and multiple-passes group, respectively) in terms of the good outcome defined as modified Rankin Scale of 0-2 at 90 days after onset. We estimated the odds ratios, safety and mortality adjusting for confounders.

RESULTS

Among 2420 patients registered, 1281 patients treated with endovascular therapy. 829 patients were analyzed (557 patients in single-pass and 272 patients in multiple-passes group). Patient characteristics were almost similar between two groups. The good outcome was more observed of patients in the single groups (51.5% vs 39.3%). The adjusted odds ratio of single pass of good outcome was 1.92 (95% confidence interval, 1.37-2.69). The frequencies of symptomatic intracranial hemorrhage were similar between the two groups.

CONCLUSION

Single pass recanalization was associated with good clinical outcome on real-world settings in Asian population.

Efficacy of Solitaire AB stent-release angioplasty in acute middle cerebral artery atherosclerosis obliterative cerebral infarction

BACKGROUND

In both national and international studies, the safety and effectiveness of treatment with the Solitaire stent in patients with ischemic stroke caused by acute large vessel occlusion were good, and the disability rate was significantly reduced. However, there are currently only a few reports on the differences in endovascular treatment for different etiological classifications, especially in the anterior cranial circulation, aorta atherosclerotic stenosis, and acute thrombosis.

AIM

To investigate the efficacy of Solitaire AB stent-release angioplasty in patients with acute middle cerebral artery atherosclerosis obliterative cerebral infarction.

METHODS

Twenty-five patients with acute middle cerebral atherosclerosis obliterative cerebral infarction were retrospectively enrolled in this study from January 2017 to December 2019. The Solitaire AB stent was used to improve anterior blood flow to maintain modified cerebral infarction thrombolysis [modified thrombolysis in cerebral infarction (mTICI)] at the 2b/3 level or above, the stent was then unfolded and released.

RESULTS

All 25 patients underwent successful surgery, with an average recanalization time of 23 min. One patient died of cerebral hemorrhage and cerebral herniation after the operation. The National Institutes of Health Stroke Scale (NIHSS) scores immediately after surgery (7.5 ± 5.6), at 24 h (5.5 ± 5.6) and at 1 wk (3.6 ± 6.7) compared with the preoperative NIHSS score (15.9 ± 4.4), were significantly different (P < 0.01). One case of restenosis was observed 3 mo after surgery (the stenosis rate was 50% without clinical symptoms), the modified Rankin scale scores were 0 points in 14 cases (56%), 1 point in 4 cases (16%), 2 points in 2 cases (8%), 3 points in 3 cases (12%), 4 points in 1 case (4%), and 6 points in 1 case (4%).

CONCLUSION

In acute middle cerebral artery atherosclerosis obliterative cerebral infarction, when the Solitaire AB stent is unfolded and the forward blood flow is maintained at mTICI level 2b/3 or higher, stent release may be a safe and effective treatment method; however, long-term observation and a larger sample size are required to verify these findings.

Non-contrast dual-energy CT virtual ischemia maps accurately estimate ischemic core size in large-vessel occlusive stroke

Dual-energy CT (DECT) material decomposition techniques may better detect edema within cerebral infarcts than conventional non-contrast CT (NCCT). This study compared if Virtual Ischemia Maps (VIM) derived from non-contrast DECT of patients with acute ischemic stroke due to large-vessel occlusion (AIS-LVO) are superior to NCCT for ischemic core estimation, compared against reference-standard DWI-MRI. Only patients whose baseline ischemic core was most likely to remain stable on follow-up MRI were included, defined as those with excellent post-thrombectomy revascularization or no perfusion mismatch. Twenty-four consecutive AIS-LVO patients with baseline non-contrast DECT, CT perfusion (CTP), and DWI-MRI were analyzed. The primary outcome measure was agreement between volumetric manually segmented VIM, NCCT, and automatically segmented CTP estimates of the ischemic core relative to manually segmented DWI volumes. Volume agreement was assessed using Bland–Altman plots and comparison of CT to DWI volume ratios. DWI volumes were better approximated by VIM than NCCT (VIM/DWI ratio 0.68 ± 0.35 vs. NCCT/DWI ratio 0.34 ± 0.35; P < 0.001) or CTP (CTP/DWI ratio 0.45 ± 0.67; P < 0.001), and VIM best correlated with DWI (r_VIM = 0.90; r_NCCT = 0.75; r_CTP = 0.77; P < 0.001). Bland–Altman analyses indicated significantly greater agreement between DWI and VIM than NCCT core volumes (mean bias 0.60 [95%AI 0.39–0.82] vs. 0.20 [95%AI 0.11–0.30]). We conclude that DECT VIM estimates the ischemic core in AIS-LVO patients more accurately than NCCT.

Impact of the reperfusion status for predicting the final stroke infarct using deep learning

BACKGROUND

Predictive maps of the final infarct may help therapeutic decisions in acute ischemic stroke patients. Our objectives were to assess whether integrating the reperfusion status into deep learning models would improve their performance, and to compare them to current clinical prediction methods.

METHODS

We trained and tested convolutional neural networks (CNNs) to predict the final infarct in acute ischemic stroke patients treated by thrombectomy in our center. When training the CNNs, non-reperfused patients from a non-thrombectomized cohort were added to the training set to increase the size of this group. Baseline diffusion and perfusion-weighted magnetic resonance imaging (MRI) were used as inputs, and the lesion segmented on day-6 MRI served as the ground truth for the final infarct. The cohort was dichotomized into two subsets, reperfused and non-reperfused patients, from which reperfusion status specific CNNs were developed and compared to one another, and to the clinically-used perfusion-diffusion mismatch model. Evaluation metrics included the Dice similarity coefficient (DSC), precision, recall, volumetric similarity, Hausdorff distance and area-under-the-curve (AUC).

RESULTS

We analyzed 109 patients, including 35 without reperfusion. The highest DSC were achieved in both reperfused and non-reperfused patients (DSC = 0.44 ± 0.25 and 0.47 ± 0.17, respectively) when using the corresponding reperfusion status-specific CNN. CNN-based models achieved higher DSC and AUC values compared to those of perfusion-diffusion mismatch models (reperfused patients: AUC = 0.87 ± 0.13 vs 0.79 ± 0.17, P < 0.001; non-reperfused patients: AUC = 0.81 ± 0.13 vs 0.73 ± 0.14, P < 0.01, in CNN vs perfusion-diffusion mismatch models, respectively).

CONCLUSION

The performance of deep learning models improved when the reperfusion status was incorporated in their training. CNN-based models outperformed the clinically-used perfusion-diffusion mismatch model. Comparing the predicted infarct in case of successful vs failed reperfusion may help in estimating the treatment effect and guiding therapeutic decisions in selected patients.

Defining reperfusion post endovascular therapy in ischemic stroke using MR-dynamic contrast enhanced perfusion

OBJECTIVES

Cerebral blood flow (CBF) measurements after endovascular therapy (EVT) for acute ischemic stroke are important to distinguish early secondary injury related to persisting ischemia from that related to reperfusion when considering clinical response and infarct growth.

METHODS

We compare reperfusion quantified by the modified Thrombolysis in Cerebral Infarction Score (mTICI) with perfusion measured by MRI dynamic contrast-enhanced perfusion within 5 h of EVT anterior circulation stroke. MR perfusion (rCBF, rCBV, rTmax, rT0) and mTICI scores were included in a predictive model for change in NIHSS at 24 h and diffusion-weighted imaging (DWI) lesion growth (acute to 24 h MRI) using a machine learning RRELIEFF feature selection coupled with a support vector regression.

RESULTS

For all perfusion parameters, mean values within the acute infarct for the TICI-2b group (considered clinically good reperfusion) were not significantly different from those in the mTICI <2b (clinically poor reperfusion). However, there was a statistically significant difference in perfusion values within the acute infarct region of interest between the mTICI-3 group versus both mTICI-2b and <2b (p = 0.02). The features that made up the best predictive model for change in NIHSS and absolute DWI lesion volume change was rT0 within acute infarct ROI and admission CTA collaterals respectively. No other variables, including mTICI scores, were selected for these best models. The correlation coefficients (Root mean squared error) for the cross-validation were 0.47 (13.7) and 0.51 (5.7) for change in NIHSS and absolute DWI lesion volume change.

CONCLUSION

MR perfusion following EVT provides accurate physiological approach to understanding the relationship of CBF, clinical outcome, and DWI growth.

ADVANCES IN KNOWLEDGE

MR perfusion CBF acquired is a robust, objective reperfusion measurement providing following recanalization of the target occlusion which is critical to distinguish potential therapeutic harm from the failed technical success of EVT as well as improve the responsiveness of clinical trial outcomes to disease modification.

Incidence and Prognostic Impact of Intracranial Hemorrhage after Endovascular Treatment for Acute Large Vessel Occlusion

INTRODUCTION

Endovascular treatment (EVT) is effective against acute cerebral large vessel occlusion (LVO). However, it has been associated with a high incidence of intracranial hemorrhage (ICH). Because the incidence of ICH and prognostic impact of ICH were not scrutinized in general patients, we investigated the impact of ICH after EVT on functional outcome at 90 days in patients with acute LVO.

METHODS

RESCUE-Japan Registry 2 was a multicenter registry that enrolled 2,420 consecutive patients with acute LVO within 24 h of onset. We analyzed 1,281 patients who received EVT and compared the functional outcomes between those with and without ICH (ICH and no-ICH groups, respectively) within 24 h after EVT. We explored the factors associated with ICH and prognostic impact of symptomatic ICH (SICH) among patients with ICH. We estimated the adjusted odds ratios (ORs) for good functional outcome as modified Rankin Scale scores 0-2 and mortality. We also explored the prognostic impact of symptomatic ICH (SICH) among patients with ICH.

RESULTS

ICH occurred in 333 patients (26.0%). Several factors such as perioperative edaravone, stent retriever, and baseline glucose were associated with development of ICH within 24 h. A good outcome was observed in 80 (24.0%) and 454 (47.9%) patients in the ICH and no-ICH groups, respectively, and the adjusted OR was 0.3 (95% confidence interval [CI] = 0.2-0.5, p < 0.0001). Incidence of mortality within 90 days was not significantly different between the groups (adjusted OR 1.2; 95% CI: 0.7-1.9, p = 0.5). SICH was observed in 36 (10.8%) of 333 patients with ICH, and the good outcomes were 8.3 and 25.9% in patients with SICH and asymptomatic ICH (AICH), respectively (p = 0.02). Mortality at 90 days was 30.6 and 7.1% in patients with SICH and AICH, respectively (p < 0.0001).

CONCLUSIONS

The functional outcomes at 90 days were significantly worse in patients who developed ICH after receiving EVT for acute LVO, but the mortality was generally similar.

Impact of carotid tortuosity on outcome after endovascular thrombectomy

BACKGROUND AND OBJECTIVES

Endovascular thrombectomy (EVT) is efficacious in patients with large vessel occlusion stroke (LVO). We explored whether internal carotid (ICA) tortuosity increases the technical difficulty of EVT thereby lowering the chances of successful recanalization and favorable outcomes.

PATIENTS AND METHODS

Consecutive patients with LVO and patent ICAs who underwent EVT were included. Carotid tortuosity was determined on pre-EVT CTA and classified by raters blinded to outcomes into: type 1-straight ICA trunk and type 2-severe tortuosity potentially impeding adequate catheter placement. Thrombolysis in cerebral infarction (TICI) 2b-3 was considered successful recanalization, and 90-day-modified Rankin Scale ≤ 2 was considered favorable functional outcome.

RESULTS

Among 302 patients (mean age 70 ± 15, median NIHSS 17), 53% had type 1, and 47% type 2 tortuosity. Overall, 85% had successful recanalization. Patients with type 2 tortuosity were significantly older (p < 0.0001) and less frequently achieved successful recanalization (80% vs. 90%; p = 0.019) but had similar outcomes compared with those without tortuosity. On regression analysis, marked tortuosity was associated with lower chances of successful recanalization (OR 0.43 95% CI 0.20-0.92) but had no effect on clinical outcomes.

CONCLUSIONS

Carotid tortuosity does not appear to impact the likelihood of favorable functional outcome but may influence recanalization.

Post-stroke ASPECTS predicts outcome after thrombectomy

PURPOSE

Infarct growth and final infarct volume are established outcome modifiers following endovascular thrombectomy (EVT) for patients with large vessel occlusion stroke (LVO). Simple techniques for final infarct volume measurement are lacking, and therefore, we tested whether post-EVT ASPECTS can be used for prognostic evaluation after EVT.

METHODS

Infarct size at baseline was measured in a prospective cohort of patients with LVO that underwent EVT with the ASPECTS score on admission non-contrast CT. Final infarct size was assessed with a post-EVT ASPECTS (ASPECTS-POST) obtained from a follow-up CT 24-72 h post-EVT. The best performing ASPECTS-POST was chosen based on comparisons of different thresholds. Outcome measures included survival rates and modified Rankin Score at 90 days.

RESULTS

A total of 272 patients were included and 166 of them had an ASPECTS-POST ≥ 7. ASPECTS-POST ≥ 7 was associated with increased likelihood of favorable outcome at 90 days (67% vs. 21%, p < 0.001) with sensitivity, specificity, and positive and negative predictive values of 86%, 58%, 61%, and 85%, respectively. On multivariate analysis, ASPECTS-POST ≥ 7 was found to be a significant modifier of favorable outcome (Odds Ratio [OR] 6.2, 95% confidence intervals [CI] 3.1-12.4) and survival (OR 5.8 95% CI 2.4-14.3).

CONCLUSION

ASPECTS can be rapidly and easily obtained from the post-EVT NCCT and ASPECTS-POST ≥ 7 correlates with good outcome.

An Observational Study Investigating the Need for Decompressive Hemicraniectomy after Thrombectomy in Acute Ischemic Stroke of the Middle Cerebral Artery Territory

OBJECTIVE

The frequency incidence of decompressive hemicraniectomy following intra-arterial thrombectomy (IAT) in acute ischemic stroke (AIS) involving the middle cerebral artery (MCA) territory was assessed as a surrogate for morbidity.

METHODS

A single-institution retrospective chart review was conducted involving 209 consecutive patients between September 2014 and May 2017 with infarctions affecting the MCA territory and who subsequently underwent IAT. The outcomes of interest included the frequency of hemicraniectomy following IAT and the effects of intravenous tissue plasminogen activator (IV tPA) use and primary occlusion site on the Thrombolysis in Cerebral Infarction (TICI) score.

RESULTS

Thirty-one patients were excluded for infarctions not involving the MCA territory. A total of 178 patients were included in the study. Sixty-eight patients (38.6%) had infarctions of less than one-third of the MCA territory, 50 (28.4%) had infarctions between one-third and two-thirds, and 58 (33%) had infarctions involving greater than two-thirds with 54.3% suffering infarctions of the left side. Only four patients (2.2%) required a hemicraniectomy with no statistically significant association found between TICI score and hemicraniectomy (p=0.41) or between administration of IV tPA and hemicraniectomy (p=0.36). The primary occlusion site was found to influence TICI score (p=0.045).

CONCLUSION

A very small number of patients required hemicraniectomy after IAT as compared to previously published rates in the literature. However, several factors may prevent the patient from being an appropriate hemicraniectomy candidate in the first place and the small number of these patients in this study limits statistical analysis. The variables that determine a patient's candidacy for decompressive hemicraniectomy remains multi-factorial.

Theophylline as an Add-On to Thrombolytic Therapy in Acute Ischemic Stroke: A Randomized Placebo-Controlled Trial

BACKGROUND AND PURPOSE

Delayed recanalization increases the risk of infarct growth and poor clinical outcome in acute ischemic stroke. The vasoactive agent theophylline has shown neuroprotective effects in animal stroke models but inconclusive results in case series and randomized clinical trials. The primary objective of this study was to evaluate whether theophylline, as an add-on to thrombolytic therapy, is safe and effective in acute ischemic stroke patients.

METHODS

The TEA-Stroke trial (The Theophylline in Acute Ischemic Stroke) was an investigator-initiated 2-center, proof-of-concept, phase II clinical study with a randomized, double-blinded, placebo-controlled design. The main inclusion criteria were magnetic resonance imaging-verified acute ischemic stroke, moderate to severe neurological deficit (National Institutes of Health Stroke Scale score of ≥4), and treatment with thrombolysis within 4.5 hours of onset. Participants were randomly assigned in the ratio 1:1 to either 220 mg of intravenous theophylline or placebo. The co-primary outcomes were early clinical improvement on the National Institutes of Health Stroke Scale score and infarct growth on magnetic resonance imaging at 24-hour follow-up.

RESULTS

Theophylline as an add-on to thrombolytic therapy improved the National Institutes of Health Stroke Scale score at 24 hours by mean 4.7 points (SD, 5.6) compared with an improvement of 1.3 points (SD, 7.5) in the control group (P=0.044). Mean infarct growth was 141.6% (SD, 126.5) and 104.1% (SD, 62.5) in the theophylline and control groups, respectively (P=0.146). Functional independence at 90 days was 61% in the theophylline group and 58% in the control group (P=0.802).

CONCLUSIONS

This proof-of-concept trial investigated theophylline administration as an add-on to thrombolytic therapy in acute ischemic stroke. The co-primary end points early clinical improvement and infarct growth at 24-hour follow-up were not significantly different after post hoc correction for multiplicity (Bonferroni technique). The small study size precludes a conclusion as to whether theophylline has a neuroprotective effect but provides a promising clinical signal that may support a future clinical trial. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: EudraCT number 2013-001989-42.

2B, 2C, or 3

Background and Purpose—

A score of ≥2B on the modified Thrombolysis in Cerebral Infarction scale is generally regarded as successful reperfusion after endovascular treatment for ischemic stroke. The extended Thrombolysis in Cerebral Infarction (eTICI) includes a 2C grade, which indicates near-perfect reperfusion. We investigated how well the respective eTICI scores of 2B, 2C, and 3 correlate with clinical outcome after endovascular treatment.

Methods—

We used data from the Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands Registry, a prospective, nationwide registry of endovascular treatment in the Netherlands. We included patients with a proximal intracranial occlusion of the anterior circulation for whom final antero-posterior and lateral digital subtraction angiography imaging was available. Our primary outcome was the distribution on the modified Rankin Scale at 90 days per eTICI grade. We performed (ordinal) logistic regression analyses, using eTICI 2B as reference group, and adjusted for potential confounders.

Results—

In total, 2807/3637 (77%) patients met the inclusion criteria. Of these, 17% achieved reperfusion grade eTICI 0 to 1, 14% eTICI 2A, 25% eTICI 2B, 12% eTICI 2C, and 32% eTICI 3. Groups differed in terms of age ( P <0.001) and occlusion location ( P <0.01). Procedure times decreased with increasing reperfusion grades. We found a positive association between reperfusion grade and functional outcome, which continued to increase after eTICI 2B (adjusted common odds ratio, 1.22 [95% CI, 0.96–1.57] for eTICI 2C versus 2B; adjusted common odds ratio, 1.33 [95% CI, 1.09–1.62] for eTICI 3 versus 2B).

Conclusions—

Our results indicate a continuous relationship between reperfusion grade and functional outcome, with eTICI 3 leading to the best outcomes. Although this implies that interventionists should aim for the highest possible reperfusion grade, further research on the optimal strategy is necessary.

Two cases of successful recanalization for acute cerebral artery embolism during perioperative period of radiofrequency ablation for atrial fibrillation

To explore the strategy of acute cerebral artery embolism after radiofrequency catheter ablation (RFA) for atrial fibrillation (AF). Reporting two cases with acute cerebral infarction after RFA for AF. Two patients were both with AF, and intracardiac thrombus was excluded through transesophageal echocardiogram (TEE) before procedure. Approach of ablation: circumferential pulmonary vein ablation in left atrium to isolate pulmonary vein plus linear ablation in the top and bottom of left atrium (BOX procedure). They both received Dabigatran Etexilate 110 mg twice daily, starting 6 hr after ablation. Symptoms of major stroke appeared 30 hr after ablation in Case 1. Occlusion was detected in M1 segment of the left middle cerebral artery by MRI 2 hr after symptoms onset. Intravenous thrombolysis was given immediately. In Case 2, the patient presented symptoms of major stroke 34 hr after ablation and occlusion in the basilar artery was confirmed by MRI 4.5 hr after symptoms onset. Although it was beyond the thrombolysis time window, mechanical thrombectomy was taken 7 hr after the symptoms onset. The culprit artery was successfully revascularized in both cases. In Case 1, NIHSS score was reduced from 8 (before thrombolysis) to 0 (24 hr after thrombolysis). In Case 2, NIHSS score decreased from 18 (before embolectomy) to 3 (24 hr after embolectomy). Both of the patients live a normal life without brain function impairment and hemorrhage until the last follow‐up. Timely recanalization could attained a good cure effect when acute stoke was happened after RFA for AF.

qTICI: Quantitative assessment of brain tissue reperfusion on digital subtraction angiograms of acute ischemic stroke patients

BACKGROUND

The Thrombolysis in Cerebral Infarction (TICI) scale is an important outcome measure to evaluate the quality of endovascular stroke therapy. The TICI scale is ordinal and observer-dependent, which may result in suboptimal prediction of patient outcome and inconsistent reperfusion grading.

AIMS

We present a semi-automated quantitative reperfusion measure (quantified TICI (qTICI)) using image processing techniques based on the TICI methodology.

METHODS

We included patients with an intracranial proximal large vessel occlusion with complete, good quality runs of anteroposterior and lateral digital subtraction angiography from the MR CLEAN Registry. For each vessel occlusion, we identified the target downstream territory and automatically segmented the reperfused area in the target downstream territory on final digital subtraction angiography. qTICI was defined as the percentage of reperfused area in target downstream territory. The value of qTICI and extended TICI (eTICI) in predicting favorable functional outcome (modified Rankin Scale 0-2) was compared using area under receiver operating characteristics curve and binary logistic regression analysis unadjusted and adjusted for known prognostic factors.

RESULTS

In total, 408 patients with M1 or internal carotid artery occlusion were included. The median qTICI was 78 (interquartile range 58-88) and 215 patients (53%) had an eTICI of 2C or higher. qTICI was comparable to eTICI in predicting favorable outcome with area under receiver operating characteristics curve of 0.63 vs. 0.62 (P = 0.8) and 0.87 vs. 0.86 (P = 0.87), for the unadjusted and adjusted analysis, respectively. In the adjusted regression analyses, both qTICI and eTICI were independently associated with functional outcome.

CONCLUSION

qTICI provides a quantitative measure of reperfusion with similar prognostic value for functional outcome to eTICI score.

MT in anticoagulated patients

Mechanical thrombectomy (MT) is one of the main treatments for acute ischemic stroke (AIS) in patients on effective anticoagulation. The use of direct oral anticoagulants (DOA) has increased, given their efficacy and safety profile compared to vitamin K antagonists (VKA). We compared procedural and clinical outcomes of MT in patients on DOA and VKA treatment before stroke onset. We analyzed 2 groups from the Endovascular Treatment in Ischemic Stroke prospective registry: patients on DOA and patients on VKA treated by MT without thrombolysis. Generalized linear mixed models including center as random effect were used to compare angiographic (rates of reperfusion at end of procedure, number of passes >2, procedural complications) and clinical (favorable and excellent outcome, 90-day all-cause mortality, and hemorrhagic complications) outcomes according to anticoagulation subgroups. Comparisons were adjusted for prespecified confounders (age, admission NIH Stroke Scale score) as well as for meaningful baseline between-group differences. Among 221 patients included, more DOA-treated patients (n = 115, 52%) achieved successful (modified Thrombolysis in Cerebral Infarction score [mTICI] 2b/3) or near complete (mTICI 2c/3) reperfusion at the procedure end than did VKA-treated patients, with an adjusted odds ratio (OR) for DOA vs VKA of 3.27 (95% confidence interval [CI], 1.40–7.65) and 2.00 (95% CI, 1.08–3.73), respectively. DOA-treated patients had a lower 90-day mortality risk with an adjusted OR of 0.47 (95% CI, 0.24–0.89) and a better excellent outcome OR of 2.40 (1.10–5.27). There was no significant between-group difference in hemorrhagic or procedural complications. The study highlights the benefits of DOA compared to VKA. Regarding mortality, excellent outcomes, and recanalization rate, DOA appears to provide a favorable setting for MT treatment in AIS.

Comparative Safety and Efficacy of Modified TICI 2b and TICI 3 Reperfusion in Acute Ischemic Strokes Treated With Mechanical Thrombectomy

BACKGROUND

Mechanical thrombectomy (MT) is the current standard of care for acute ischemic stroke (AIS) patients with emergent large-vessel occlusions (ELVO). Successful reperfusion of ELVO is traditionally defined by modified Thrombolysis in Cerebral Infarction (mTICI) grades of 2b or 3.

OBJECTIVE

To evaluate the comparative safety and efficacy of mTICI 2b and mTICI 3 reperfusion in AIS patients treated with MT.

METHODS

Consecutive ELVO patients who underwent MT at 6 high-volume centers were included in this analysis. Standard safety (3-mo mortality, symptomatic intracranial hemorrhage [sICH]) and efficacy (absolute and relative reduction in NIHSS-scores during hospitalization, functional-improvement [shift analysis in mRS-scores], and functional-independence [mRS-scores of 0-2] at 3-mo) were compared between patients who had mTICI 2b and mTICI 3 reperfusion post MT.

RESULTS

A total of 416 ELVO patients achieved successful reperfusion with mTICI 2b (n = 216) and mTICI 3 (n = 200) following MT. The mTICI 3 group had significantly (P < .05) greater absolute (11 vs 9 points) and relative (77% vs 63%) reduction in NIHSS-scores during hospitalization, lower sICH (6% vs 12%), and higher 3-mo functional-independence (55% vs 44%) rates. Successful reperfusion with mTICI 3 was independently (P < .05) associated with greater absolute and relative reduction in NIHSS-scores during hospitalization as well as higher odds of 3-mo functional improvement (common odds ratios: 1.67; 95% confidence interval: 1.10-2.56) and functional independence (odds ratio: 2.08; 95% confidence interval: 1.22-3.53) in multivariable regression models adjusting for confounders.

CONCLUSION

Successful reperfusion with mTICI 3 was associated with greater neurological improvement during hospitalization and better 3-mo functional outcomes in comparison to mTICI 2b reperfusion.

Guidelines for the Early Management of Patients With Acute Ischemic Stroke: 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

Background and Purpose- The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations in a single document for clinicians caring for adult patients with acute arterial ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 Acute Ischemic Stroke (AIS) Guidelines and are an update of the 2018 AIS Guidelines. Methods- Members of the writing group were appointed by the American Heart Association (AHA) Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. An update of the 2013 AIS Guidelines was originally published in January 2018. This guideline was approved by the AHA Science Advisory and Coordinating Committee and the AHA Executive Committee. In April 2018, a revision to these guidelines, deleting some recommendations, was published online by the AHA. The writing group was asked review the original document and revise if appropriate. In June 2018, the writing group submitted a document with minor changes and with inclusion of important newly published randomized controlled trials with >100 participants and clinical outcomes at least 90 days after AIS. The document was sent to 14 peer reviewers. The writing group evaluated the peer reviewers' comments and revised when appropriate. The current final document was approved by all members of the writing group except when relationships with industry precluded members from voting and by the governing bodies of the AHA. These guidelines use the American College of Cardiology/AHA 2015 Class of Recommendations and Level of Evidence and the new AHA guidelines format. Results- These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings. Conclusions- These guidelines provide general recommendations based on the currently available evidence to guide clinicians caring for adult patients with acute arterial ischemic stroke. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

Early hemodynamic predictors of good outcome and reperfusion injury after endovascular treatment

Objective

To find early hemodynamic predictors of outcome and reperfusion injury in patients with acute ischemic stroke due to anterior circulation large artery occlusion (LAO) after endovascular treatment (EVT).

Methods

Serial transcranial color-coded sonography examinations assessed the vessel status and cerebral hemodynamics of 185 (109 [58.9%] men, mean age 69.5 ± 12.3 years) consecutive patients with acute anterior circulation LAO soon after, at 48 hours after, and 1 week after EVT.

Results

Successful recanalization (odds ratio [OR] 0.25, 95% confidence interval [CI] 0.11–0.61) and normal peak systolic velocity (PSV) ratio (PSV of recanalized middle cerebral artery/PSV of contralateral middle cerebral artery) at 48 hours (OR 0.22, 95% CI 0.15–0.64) and after 1 week (OR 0.11, 95% CI 0.07–0.31) from EVT were independent predictors of good outcome at 3 months. Thrombectomy failure (OR 10.22, 95% CI 1.47–45.53) and pathologic PSV ratio at 1 week from EVT (OR 15.23, 95% CI 4.54–46.72) were associated with a worse 90-day outcome. Patients who subsequently developed postinterventional intracranial hemorrhage (ICH) showed a higher mean PSV ratio (3.5 ± 0.2 vs 2.4 ± 0.1, p < 0.0001) soon after successful recanalization. In multivariate analysis, early PSV ratio was independently associated with postprocedural ICH (OR 8.474, 95% CI 3.066–45.122, p < 0.01]. At 1 week from EVT, 15 of 21 (71.4%) patients with ICH who resumed normal PSV values had a better 90-day outcome (modified Rankin Scale score 0–2: 40% vs 0%).

Conclusion

Post-EVT ultrasound monitoring of stroke patients might be an effective bedside method for assessing treatment efficacy, shedding light on outcome variability and identifying patients at increased risk of ICH.

Impact of previous stroke on outcome after thrombectomy in patients with large vessel occlusion

Background

Many patients with large vessel occlusion (LVO) who are otherwise candidates for endovascular treatment (EVT) have had previous strokes. We aimed to examine the effect of previous stroke on outcome after EVT.

Methods

Consecutive patients with LVO were prospectively entered into a National Acute Stroke registry of patients undergoing EVT. Patients treated with EVT were divided into those with and without previous strokes. The rates of favorable reperfusion status, mortality, and excellent outcome at 90 days post-stroke as well as symptomatic intracranial hemorrhage (sICH) were evaluated.

Results

A total of 390 underwent EVT and 35 had previous strokes. Patients with previous strokes were significantly older; more frequently had a history of prior myocardial infarction and more often had pre-existing functional disability. Favorable target vessel recanalization was less frequently achieved in patients with previous strokes (60% vs. 82%; p = 0.005) and ordinal regression analysis for functional outcome revealed higher frequency of deterioration at three months in patients with previous strokes. Nevertheless, 9% of these patients maintained their previous disability state and sICH rates did not differ between the groups. Mortality rates at one year post stroke were significantly higher in patients with previous strokes (37% vs. 16%; p = 0.005).

Conclusions

Previous strokes are associated with higher likelihoods of mortality and unfavorable outcome in patients with LVO undergoing EVT. However, because some of these patients maintain their previous disability state, the presence of previous stroke should not be used as an exclusion criterion from EVT.

Ultrasound Identification of Patients at Increased Risk of Intracranial Hemorrhage After Successful Endovascular Recanalization for Acute Ischemic Stroke

BACKGROUND

Intracranial hemorrhage (ICH) is the most feared complication of endovascular treatment (EVT) for acute ischemic stroke because of anterior circulation large vessel occlusion (LVO). The purpose of this study was to identify cerebral hemodynamic predictors of ICH and poor outcome in patients with successful recanalization.

METHODS

Serial transcranial color-coded sonography (TCCS) examinations assessed vessel status and cerebral hemodynamics of 226 (mean age, 69.8 ± 12.5 years; 130 men [57.5%]) consecutive patients with acute anterior circulation LVO at 48 hours and 1 week after EVT. Middle cerebral artery peak systolic velocity (PSV_MCA) and PSV_MCA ratio (recanalized PSV_MCA/contralateral PSV_MCA) were recorded.

RESULTS

Out of 180 successfully recanalized patients (79.6%), 28 patients (15.5%) had ICH. They more often had arterial hypertension (25/28 [89.3%] vs. 106/152 [69.7%], P = 0.04), a more severe stroke syndrome (18 [range, 10-23] vs. 16 [range, 5-26], P = 0.01), a worse clinical outcome (90-day modified Rankin Scale [mRS] score 3-5: 16/28 [57.1%] vs. 42/152 [27.6%], P = 0.004), and soon after EVT showed a significantly higher mean PSV_MCA ratio (3.4 ± 0.1 vs. 2.4 ± 0.1, P < 0.0001) than patients without ICH, respectively. In multivariate analysis, early PSV_MCA ratio was independently associated with postinterventional ICH (odds ratio, 13.379; 95% confidence interval, 2.466-50.372; P < 0.01). The patients with ICH (19/28 [67.9%]) who resumed normal PSV_MCA values at 1 week after EVT had a better outcome (90-day mRS score 0-2: 8/19 [42.1%] vs. 0/9 [0%], respectively).

CONCLUSIONS

Early TCCS detection of a high PSV_MCA ratio in successfully recanalized stroke patients indicates an increased risk of ICH, whereas cerebral hemodynamics normalization at 1 week in patients with postinterventional ICH predicts a relatively better 3-month outcome.

Reperfusion Changes After Stroke and Practical Approaches for Neuroprotection

Reperfusion is the first line of care in a growing number of eligible acute ischemic stroke patients. Early reperfusion with thrombolytic drugs and endovascular mechanical devices is associated with improved outcome and lower mortality rates compared with natural history. Reperfusion is not without risk, however, and may result in reperfusion injury, which manifests in hemorrhagic transformation, brain edema, infarct progression, and neurologic worsening. In this article, the functional and structural changes and underlying molecular mechanisms of ischemia and reperfusion are reviewed. The pathways that lead to reperfusion injury and novel neuroprotective strategies with endogenous properties are discussed.

Diffusion-weighted imaging lesion growth occurs despite recanalization in acute ischemic stroke: Implications for future treatment trials

Background

A proportion of patients presenting with acute small ischemic strokes have poor functional outcomes, even following rapid recanalization treatment.

Aims

Infarct growth may occur even after successful recanalization and could represent an appropriate endpoint for future stroke therapy trials.

Methods

Magnetic resonance diffusion-weighted imaging lesion volumes were obtained at 5 h (initial posttreatment) and 24 h (follow-up) after acute stroke treatment for n = 33 in ischemic stroke patients. Sample sizes per arm (90% power, 30% effect size) for diffusion-weighted imaging lesion growth between initial and 24 h, early change in the National Institutes of Health Stroke Scale between pre- and 24 h, National Institutes of Health Stroke Scale at 24 h, and diffusion-weighted imaging lesion volume at 24 h were estimated to power a placebo-controlled stroke therapy trial.

Results

For patients with poor recanalization (modified thrombolysis in cerebral infarction <2 a; modified arterial occlusion lesion = 0–2) (n = 11), the median diffusion-weighted imaging lesion growth was 8.1 (interquartile range: 4.5, 22.4) ml and with good recanalization (modified thrombolysis in cerebral infarction =2 b or 3; modified arterial occlusion lesion = 3) (n = 22), the median diffusion-weighted imaging lesion growth was 10.0 (interquartile range: 6.0, 28.2) ml ( P = 0.749). When considering a 30% effect size, the sample size required per arm to achieve significance in an acute stroke study would be: (1) N = 49 for the diffusion-weighted imaging lesion growth between initial posttreatment and follow-up time points, (2) N = 65 for the change in the National Institutes of Health Stroke Scale between admission and 24 h, (3) N = 259 for the National Institutes of Health Stroke Scale at 24 h, and (4) N = 256 for diffusion-weighted imaging volume at 24 h.

Conclusion

Despite best efforts to recanalize the ischemic brain, early diffusion-weighted imaging lesion growth still occurs. Treatment trials in stroke should consider early diffusion-weighted imaging lesion growth as a surrogate outcome measure to significantly reduce sample sizes.

Systematic review and meta-analysis on outcome differences among patients with TICI2b versus TICI3 reperfusions: success revisited

OBJECTIVE

A reperfusion quality of thrombolysis in cerebral infarction (TICI)≥2b has been set as the therapeutic angiography target for interventions in patients with acute ischaemic stroke. This study addresses whether the distinction between TICI2b and TICI3 reperfusions shows a clinically relevant difference on functional outcome.

METHODS

A systematic literature review and meta-analysis was carried out and presented in conformity with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria to test the primary hypothesis that TICI2b and TICI3 reperfusions are associated with different rates of modified Rankin Scale (mRS) ≤2 at day 90. Secondary endpoints included rates of haemorrhagic transformations, mortality and excellent functional outcome (mRS ≤1). Summary estimates of ORs (sOR) with 95% CI were calculated using the inverse variance heterogeneity model accounting for multiple true effect sizes.

RESULTS

Fourteen studies on 2379 successfully reperfused patients were included (1131 TICI3, 1248 TICI2b). TICI3 reperfusions were associated with higher rates of functional independence (1.74, 95% CI 1.44 to 2.10) and excellent functional outcomes (2.01, 95% CI 1.60 to 2.53), also after including adjusted estimates. The safety profile of patients with TICI3 was superior, as demonstrated by lower rates of mortality (sOR 0.59, 95% CI 0.37 to 0.92) and symptomatic intracranial haemorrhages (sOR 0.42, 95% CI 0.25 to 0.71).

CONCLUSION

TICI3 reperfusions are associated with superior outcome and better safety profiles than TICI2b reperfusions. This effect seems to be independent of time and collaterals. As reperfusion quality is the most important modifiable predictor of patients' outcome, a more conservative definition of successful therapy and further evaluation of treatment approaches geared towards achieving TICI3 reperfusions are desirable.

Reperfusion and Clinical Outcomes in Acute Ischemic Stroke: Systematic Review and Meta-Analysis of the Stent-Retriever-Based, Early Window Endovascular Stroke Trials

Objective

To explore the effects of reperfusion grade rates on clinical outcomes in the setting of stent-retriever-based reperfusion therapy for anterior circulation stroke in early time windows.

Methods

Systematic searching of Medline and Embase databases was performed to identify stroke trials of stent-retriever-based therapy versus standard care. Mixed effects meta-regression was used to analyze the trial-level association between reperfusion rates and clinical outcomes.

Results

A total of five trials met the inclusion criteria (n = 1,287). Rates of successful reperfusion [modified thrombolysis in cerebral ischemia grade 2b/3] demonstrated strong evidence for an association with good functional outcomes [modified Rankin scale score (mRS) 0-2] OR 1.59 (95% CI 1.16, 2.19) p = 0.019 and very strong evidence for an association with excellent functional outcomes (mRS 0-1) OR 2.10 (95% CI 1.46, 3.01) p = 0.007. In addition, there was weak evidence for an association with symptomatic intracranial hemorrhage OR 0.54 (95% CI 0.28, 1.04) p = 0.057 and mortality OR 0.69 (95% CI 0.69, 1.01) p = 0.053.

Conclusion

In early, stent-retriever-based acute ischemic stroke treatment, reperfusion appears to be a major predictor of outcomes. Every 10% increase in the rates of successful reperfusion is associated with an 11% increase in the probability of achieving good and 17% increase in the probability of achieving excellent outcomes. Symptomatic intracranial hemorrhage and mortality may be decreased as reperfusion rates are improved.

Arterial diameter and the gender disparity in stroke thrombectomy outcomes

BACKGROUND

Compared with males, females consistently fare worse following mechanical thrombectomy for large vessel ischemic strokes. Understanding why this gender disparity occurs may guide improvements in future treatment strategies. In this study, we aim to determine whether gender differences in cerebral arterial diameter correlate with clinical outcomes following stroke thrombectomy.

METHODS

We performed an observational study of consecutive acute ischemic stroke patients undergoing mechanical thrombectomy at a single, urban tertiary care medical center. Catheter angiographic images were used to manually measure proximal segment arterial diameters in a standardized fashion. Medical record review was used to obtain relevant independent and dependent variables.

RESULTS

Ninety two patients (42 females) between June 2013 and August 2016 met inclusion criteria. Internal carotid artery (ICA) terminus diameters for males and females were 3.08 mm (SD=0.46) and 2.81 mm (SD=0.45), respectively (P=0.01). M1 segment middle cerebral artery (MCA) diameters for males and females were 2.47 mm (SD=0.30) and 2.18 mm (SD=0.31), respectively (P<0.0001). 48% of patients in the upper MCA caliber tertile attained a favorable mRS 90 day value compared with 35% in each of the lower and middle tertiles (P=0.51). Larger MCA diameters correlated with favorable discharge disposition (P=0.21).

CONCLUSIONS

These results provide limited evidence that males have larger cerebral arterial diameters than females and that larger arterial diameters may improve the odds for favorable clinical outcomes. If future studies validate these findings, arterial diameter may become a relevant variable in the design of improved thrombectomy strategies.

2018 Guidelines for the Early Management of Patients With Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

BACKGROUND AND PURPOSE

The purpose of these guidelines is to provide an up-to-date comprehensive set of recommendations for clinicians caring for adult patients with acute arterial ischemic stroke in a single document. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators. These guidelines supersede the 2013 guidelines and subsequent updates.

METHODS

Members of the writing group were appointed by the American Heart Association Stroke Council's Scientific Statements Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained. Members were not allowed to participate in discussions or to vote on topics relevant to their relations with industry. The members of the writing group unanimously approved all recommendations except when relations with industry precluded members voting. Prerelease review of the draft guideline was performed by 4 expert peer reviewers and by the members of the Stroke Council's Scientific Statements Oversight Committee and Stroke Council Leadership Committee. These guidelines use the American College of Cardiology/American Heart Association 2015 Class of Recommendations and Levels of Evidence and the new American Heart Association guidelines format.

RESULTS

These guidelines detail prehospital care, urgent and emergency evaluation and treatment with intravenous and intra-arterial therapies, and in-hospital management, including secondary prevention measures that are appropriately instituted within the first 2 weeks. The guidelines support the overarching concept of stroke systems of care in both the prehospital and hospital settings.

CONCLUSIONS

These guidelines are based on the best evidence currently available. In many instances, however, only limited data exist demonstrating the urgent need for continued research on treatment of acute ischemic stroke.

A Meta-Analysis of Observational Evidence for the Use of Endovascular Thrombectomy in Proximal Occlusive Stroke Beyond 6 Hours in Patients with Limited Core Infarct

PURPOSE

The safety and efficacy of endovascular thrombectomy (EVT) for patients with proximal occlusive stroke presenting beyond 6 hours and selected on the basis of favorable neuroimaging remains unclear.

MATERIALS AND METHODS

A systematic search was performed from four electronic databases from their inception to Jan 2017. A meta-analysis of outcomes from studies with patients treated beyond 6 hours was compared to those treated within the established 6 hour therapeutic window in randomized trials, selected using conventional imaging methods with CT/CT angiography.

RESULTS

A total of 8 articles met inclusion criteria for the study population (a prospective single-center study, 5 retrospective single-center studies and 2 retrospective multicenter studies). These were compared to the results of three prospective trials of patients treated within 6 hours selected using CT/CT angiography. For patients treated >6 hours and <6 hours respectively, the weighted mean age was 64.7 vs. 67.0 years; the presenting NIHSS was 15.7 vs. 17.1 and the time from symptom onset to puncture was 4.0 hours vs. 15.1 hours. Weighted pooled estimates of successful recanalization (TIMI 2/3 or TICI 2b/3) and favorable outcome (mRS ≤2) were similar between both groups, 70.1% vs. 70.6%, P=0.75 and 38.9% vs. 38.4%, P=0.88 respectively. Pooled mortality measured at 3 months was 22.8% for those treated >6 hours and 12.5% for <6 hours, P<0.0001. Symptomatic intracranial hemorrhage was not significantly different (10.0% vs. 7.7%, P=0.33).

CONCLUSION

When compared to established methods of patient selection, EVT employed beyond 6 hours in those selected with imaging to exclude large core infarcts achieves similar rates of recanalization, and functional outcome but there is a significant increase in mortality despite no increase in symptomatic intracranial hemorrhage.

Regional Pediatric Acute Stroke Protocol

Background and Purpose—

To evaluate hyperacute management of pediatric arterial ischemic stroke, setting up dedicated management pathways is the first recommended step to prove the feasibility and safety of such treatments. A regional pediatric stroke alert protocol including 2 centers in the Paris-Ile-de-France area, France, was established.

Methods—

Consecutive pediatric patients (28 days–18 years) with confirmed arterial ischemic stroke who had acute recanalization treatment (intravenous r-tPA [recombinant tissue-type plasminogen activator], endovascular procedure, or both) according to the regional pediatric stroke alert were retrospectively reviewed during a 40-month period.

Results—

Thirteen children, aged 3.7 to 16.6 years, had recanalization treatment. Median time from onset to magnetic resonance imaging was 165 minutes (150–300); 9 out of 13 had large-vessel occlusion. Intravenous r-tPA was used in 11 out of 13 patients, with median time from onset to treatment of 240 minutes (178–270). Endovascular procedure was performed in patients time-out for intravenous r-tPA (n=2) or after intravenous r-tPA inefficiency (n=2). No intracranial or peripheral bleeding was reported. One patient died of malignant stroke; outcome was favorable in 11 out of 12 survivors (modified Rankin Scale score 0–2).

Conclusions—

Hyperacute recanalization treatment in pediatric stroke, relying on common protocols and adult/pediatric ward collaboration, is feasible. Larger systematic case collection is encouraged.

Hemorrhagic Transformations after Thrombectomy: Risk Factors and Clinical Relevance

BACKGROUND

Hemorrhagic transformation (HT) is a major complication of acute ischemic stroke, potentially associated with clinical deterioration. We attempted to identify risk factors and evaluated clinical relevance of minor and major HTs following endovascular thrombectomy (ET) in isolated middle cerebral artery (MCA) occlusions.

METHODS

This is a retrospective single-center analysis of 409 patients with isolated MCA occlusion treated with ET. Patients' and procedural characteristics, severity of HT according to the European Cooperative Acute Stroke Study criteria, and clinical outcomes were analyzed. Multivariate logistic regression models with standard retention criteria (p < 0.1) were used to determine risk factors and clinical relevance of HT. Results are shown as adjusted OR (aOR) and respective 95% CIs. Good neurologic short-term outcome was defined as National Institutes of Health Stroke Scale (NIHSS) score <5 at the day of discharge.

RESULTS

Of 299 patients included, hemorrhagic infarction (HI) was detected in 87 patients, while 13 patients developed parenchymal hematoma (PH). Higher age (aOR 0.970, 95% CI 0.947-0.993, p = 0.012), eligibility for intravenous recombinant tissue plasminogen activator (IV rtPA; aOR 0.512, 95% CI 0.267-0.982, p = 0.044), and complete recanalization (TICI 3, aOR 0.408, 95% CI 0.210-0.789, p = 0.008) were associated with a lower risk of HI. Risk factors for HI included higher admission NIHSS score (aOR 1.080, 95% CI 1.010-1.153, p = 0.024) and higher admission glucose levels (aOR 1.493, 95% CI 1.170-1.904, p = 0.001). Further, female sex tended to be associated with a lower risk of HI (aOR 0.601, 95% CI 0.316-1.143, p = 0.121), while a statistical trend was observable for proximal MCA occlusion (aOR 1.856, 95% CI 0.945-3.646, p = 0.073) and a history of hypertension (aOR 2.176, 95% CI 0.932-5.080, p = 0.072) to increase risk of HI. Longer intervals from symptom onset to first digital subtraction angiography runs (aOR 1.013, 95% CI 1.003-1.022, p = 0.009), lower preinterventional Alberta Stroke Program Early CT score (aOR 0.536, 95% CI 0.307-0.936, p = 0.028) and wake-up stroke (aOR 18.540, 95% CI 1.352-254.276, p = 0.029) were associated with PH. Both, PH and HI were independently associated with lower rates of good neurologic outcome (aOR 0.086, 95% CI 0.008-0.902, p = 0.041 and aOR 0.282, 95% CI 0.131-0.606, p = 0.001).

CONCLUSION

Risk of HI following MCA occlusion and subsequent ET is mainly determined by factors influencing infarct severity. Good recanalization results seem to be protective against subsequent HI. Our results support the notion that occurrence of PH after ET is time dependent and risk increases with more extensive early ischemic damage. Both, HI and PH do not seem to be facilitated by bridging therapy with IV rtPA or the use of oral anticoagulants, but were independently associated with more severe neurologic disability. These results support the notion that HI is not a "benign" imaging sign.

Perfusion Angiography in Acute Ischemic Stroke

Visualization and quantification of blood flow are essential for the diagnosis and treatment evaluation of cerebrovascular diseases. For rapid imaging of the cerebrovasculature, digital subtraction angiography (DSA) remains the gold standard as it offers high spatial resolution. This paper lays out a methodological framework, named perfusion angiography, for the quantitative analysis and visualization of blood flow parameters from DSA images. The parameters, including cerebral blood flow (CBF) and cerebral blood volume (CBV), mean transit time (MTT), time-to-peak (TTP), and T_max, are computed using a bolus tracking method based on the deconvolution of the time-density curve on a pixel-by-pixel basis. The method is tested on 66 acute ischemic stroke patients treated with thrombectomy and/or tissue plasminogen activator (tPA) and also evaluated on an estimation task with known ground truth. This novel imaging tool provides unique insights into flow mechanisms that cannot be observed directly in DSA sequences and might be used to evaluate the impact of endovascular interventions more precisely.

An in vitro evaluation of distal emboli following Lazarus Cover-assisted stent retriever thrombectomy

Background

Formation of clot fragments during mechanical thrombectomy for acute ischemic stroke can occlude the distal vasculature, which may reduce the rate of good clinical outcome.

Objective

To examine the hypothesis that distal embolization can be reduced using stent retriever thrombectomy in combination with Lazarus Cover technology.

Methods

Hard, fragment-prone clots were used to create middle cerebral artery occlusions in a vascular phantom. Three different treatment strategies using Solitaire FR included: group 1—proximal flow control with an 8F balloon guide catheter (BGC), group 2—thrombectomy through a 6F conventional guide catheter (CGC), and group 3—a similar thrombectomy procedure to group 2 but including the Lazarus Cover device. The primary endpoint was distal emboli quantified by the number and size of the clot debris.

Results

The Cover-assisted stent retriever thrombectomy significantly reduced the generation of clot fragments >200 μm as compared with thrombectomy with a CGC, and was similar to the BGC group. Particle size distribution <200 μm was similar across the groups. All groups were associated with high rates of recanalization, with only one failed recanalization with partial clot retention after three passes in one experiment of stent retriever thrombectomy through a CGC. Use of the adjunctive Cover device did not prolong the procedure as compared with control groups.

Conclusions

For a fragment-prone clot, Solitaire thrombectomy in conjunction with the Cover device may lower the risk of distal embolization and is comparable to BGC-protected embolectomy.

Time to redefine success? TICI 3 versus TICI 2b recanalization in middle cerebral artery occlusion treated with thrombectomy

BACKGROUND

The Thrombolysis in Cerebral Infarction (TICI) scale is the most widely applied scoring system to grade technical results of recanalizing therapies in acute ischemic stroke (AIS). TICI 2b and TICI 3 are conventionally subsumed as 'successful recanalization'. Previous studies reported conflicting results for the clinical relevance of achieving complete (TICI 3) versus 'almost' complete reperfusion (TICI 2b).

OBJECTIVE

To examine if neurologic outcome differs significantly between TICI 2b and TICI 3 in patients with AIS with middle cerebral artery (MCA) occlusion treated 'successfully' with mechanical thrombectomy (MTE).

METHODS

Retrospective analysis of prospectively collected data from 352 consecutive patients with isolated MCA occlusion subjected to MTE between January 2007 and July 2015.

RESULTS

262 of the 277 successfully treated patients had adequate follow-up and were included. Patients (n=119) in the TICI 3 group had a lower National Institutes of Health Stroke Scale score at discharge (NIHSS-DIS; median 5 vs 7, p=0.005), and showed higher rates of strong neurologic improvement (ΔNIHSS≥8 or NIHSS-DIS≤1, 68.4% vs 37.1%, p=0.002) and favorable NIHSS outcome (NIHSS-DIS≤5, 49.2% vs 31.9%, p=0.005). Hospital stays were shorter in the TICI 3 group (median 10 vs 12 days, p=0.014). After adjusting for relevant baseline and treatment parameters, TICI 3 was independently associated with strong neurologic improvement (OR=4.3, 95% CI 2.2 to 8.3, p<0.001) and favorable NIHSS outcome (OR=3.0, 95% CI 1.5 to 6.3, p=0.003).

CONCLUSIONS

Neurologic outcome is substantially better in TICI 3 than TICI 2b patients, and hospital stays are shorter. Endovascular strategies that consequently strive to achieve TICI 3 may be warranted and cost-effective, and should be examined by future research. TICI 3 rates should be included as a safety measure in studies evaluating MTE devices and techniques.

TICI and Age: What's the Score?

BACKGROUND AND PURPOSE

Previous studies have suggested that advanced age predicts worse outcome following mechanical thrombectomy. We assessed outcomes from 2 recent large prospective studies to determine the association among TICI, age, and outcome.

MATERIALS AND METHODS

Data from the Solitaire FR Thrombectomy for Acute Revascularization (STAR) trial, an international multicenter prospective single-arm thrombectomy study and the Solitaire arm of the Solitaire FR With the Intention For Thrombectomy (SWIFT) trial were pooled. TICI was determined by core laboratory review. Good outcome was defined as an mRS score of 0-2 at 90 days. We analyzed the association among clinical outcome, successful-versus-unsuccessful reperfusion (TICI 2b-3 versus TICI 0-2a), and age (dichotomized across the median).

RESULTS

Two hundred sixty-nine of 291 patients treated with Solitaire in the STAR and SWIFT data bases for whom TICI and 90-day outcome data were available were included. The median age was 70 years (interquartile range, 60-76 years) with an age range of 25-88 years. The mean age of patients 70 years of age or younger was 59 years, and it was 77 years for patients older than 70 years. There was no significant difference between baseline NIHSS scores or procedure time metrics. Hemorrhage and device-related complications were more common in the younger age group but did not reach statistical significance. In absolute terms, the rate of good outcome was higher in the younger population (64% versus 44%, P < .001). However, the magnitude of benefit from successful reperfusion was higher in the 70 years of age and older group (OR, 4.82; 95% CI, 1.32-17.63 versus OR 7.32; 95% CI, 1.73-30.99).

CONCLUSIONS

Successful reperfusion is the strongest predictor of good outcome following mechanical thrombectomy, and the magnitude of benefit is highest in the patient population older than 70 years of age.

An in vitro porcine model evaluating a novel stent retriever for thrombectomy of the common carotid artery

OBJECTIVES

This study aimed to test the safety and efficiency of a novel stent retriever, RECO, in a swine model.

BACKGROUND

The stent retrievers show great benefit for patients with acute ischemic stroke.

METHODS

The framework of the stent was optimized. The proximal stent was closed; mechanical connection replaced the electrolysis connection and the push wire located on the longitudinal axis. After tests in vitro, the safety and thrombectomy efficiency of RECO device were evaluated by angiography and histological analysis in a swine model with placement of experimental soft or hard thrombi.

RESULTS

No device-related thrombi were observed on the perioperative term or 1 month later. The endothelial cells were intact and the smooth muscle cells did not migrate or proliferate. Device-related vasospasm was detected in 9% vessels undergoing the procedure and was alleviated after delivery of a dose of nitroglycerin. The RECO device demonstrated a high recanalization rate in the target vessels with a mean of 1.3 runs. No residual thrombi were observed under the DSA or microscope.

CONCLUSIONS

Our data indicated that RECO device was a novel, safe and effective stent based clot retriever. A phase IIa clinical trial, RESTORE, is undergoing (NCT01983644).