Abstract WMP7: Poor Reperfusion After Endovascular Therapy is Associated With Worse Outcomes Than No Intervention in the HERMES Analysis of Seven Randomized Trials

Introduction: Although the role of successful reperfusion in improved outcome after endovascular treatment (EVT) for stroke is known, there has been limited evaluation of the effects of poor reperfusion. We compared results in the HERMES collaboration between standard care and those in the EVT group with poor reperfusion.

Methods: Patient-level data were pooled in this meta-analysis of seven randomized trials comparing endovascular thrombectomy with standard care in anterior ischemic stroke. Functional outcome was assessed by ordinal analysis of the modified Rankin scale (mRS) at 90 days, comparing standard care versus EVT subjects achieving mTICI of 0 or 1 post-procedure. Analyses were adjusted for baseline prognostic variables to correct for potential imbalances.

Results: The meta-analysis included 877 subjects in the standard care group and 78 in the EVT group with mTICI 0-1 per the HERMES central imaging core laboratory. At baseline, the EVT cohort had higher NIHSS (median 19 vs 17, p=0.011), but was not significantly different from standard care in other characteristics including age, sex, ASPECTS, time to randomization, site of occlusion and alteplase administration. Subjects with poor reperfusion in the EVT group had worse mRS at 90 days than standard care, unadjusted (p=0.003) and after adjustment for baseline characteristics (common odds ratio 0.59 (0.38-0.91), p=0.016). Fewer subjects in the EVT poor-reperfusion cohort achieved mRS 0, mRS 0-1 and all other dichotomized mRS cutpoints (Figure 1). Symptomatic intracranial hemorrhage was not different between groups (3.9% vs 3.5%, p=0.75).

Conclusion: In recent endovascular trials, poor reperfusion after EVT was associated with worse outcomes than standard care in recent endovascular trials. This suggests that additional efforts to achieve reperfusion by EVT should be encouraged if deemed safe to do so.

Penumbral imaging and functional outcome in patients with anterior circulation ischaemic stroke treated with endovascular thrombectomy versus medical therapy: a meta-analysis of individual patient-level data

BACKGROUND

CT perfusion (CTP) and diffusion or perfusion MRI might assist patient selection for endovascular thrombectomy. We aimed to establish whether imaging assessments of irreversibly injured ischaemic core and potentially salvageable penumbra volumes were associated with functional outcome and whether they interacted with the treatment effect of endovascular thrombectomy on functional outcome.

METHODS

In this systematic review and meta-analysis, the HERMES collaboration pooled patient-level data from all randomised controlled trials that compared endovascular thrombectomy (predominantly using stent retrievers) with standard medical therapy in patients with anterior circulation ischaemic stroke, published in PubMed from Jan 1, 2010, to May 31, 2017. The primary endpoint was functional outcome, assessed by the modified Rankin Scale (mRS) at 90 days after stroke. Ischaemic core was estimated, before treatment with either endovascular thrombectomy or standard medical therapy, by CTP as relative cerebral blood flow less than 30% of normal brain blood flow or by MRI as an apparent diffusion coefficient less than 620 μm²/s. Critically hypoperfused tissue was estimated as the volume of tissue with a CTP time to maximum longer than 6 s. Mismatch volume (ie, the estimated penumbral volume) was calculated as critically hypoperfused tissue volume minus ischaemic core volume. The association of ischaemic core and penumbral volumes with 90-day mRS score was analysed with multivariable logistic regression (functional independence, defined as mRS score 0-2) and ordinal logistic regression (functional improvement by at least one mRS category) in all patients and in a subset of those with more than 50% endovascular reperfusion, adjusted for baseline prognostic variables. The meta-analysis was prospectively designed by the HERMES executive committee, but not registered.

FINDINGS

We identified seven studies with 1764 patients, all of which were included in the meta-analysis. CTP was available and assessable for 591 (34%) patients and diffusion MRI for 309 (18%) patients. Functional independence was worse in patients who had CTP versus those who had diffusion MRI, after adjustment for ischaemic core volume (odds ratio [OR] 0·47 [95% CI 0·30-0·72], p=0·0007), so the imaging modalities were not pooled. Increasing ischaemic core volume was associated with reduced likelihood of functional independence (CTP OR 0·77 [0·69-0·86] per 10 mL, p_interaction=0·29; diffusion MRI OR 0·87 [0·81-0·94] per 10 mL, p_interaction=0·94). Mismatch volume, examined only in the CTP group because of the small numbers of patients who had perfusion MRI, was not associated with either functional independence or functional improvement. In patients with CTP with more than 50% endovascular reperfusion (n=186), age, ischaemic core volume, and imaging-to-reperfusion time were independently associated with functional improvement. Risk of bias between studies was generally low.

INTERPRETATION

Estimated ischaemic core volume was independently associated with functional independence and functional improvement but did not modify the treatment benefit of endovascular thrombectomy over standard medical therapy for improved functional outcome. Combining ischaemic core volume with age and expected imaging-to-reperfusion time will improve assessment of prognosis and might inform endovascular thrombectomy treatment decisions.

FUNDING

Medtronic.

Survival after non-resection of colorectal cancer: the argument for including non-operatives in consultant outcome reporting in the UK

INTRODUCTION

Although the mainstay of colorectal cancer treatment remains operative, a significant proportion of patients end up without surgery. This is because they are either deemed to have no oncological benefit from the resection (too much disease) or to be unfit for major surgery (too frail). The aim of this study was to assess the proportion and survival of these two groups among the totality of practice in a tertiary unit and to discuss the implications on the conceptual understanding of outcome measures.

METHODS

Data was collected over two study periods with the total duration of four years. Patient demographics, comorbidities, cancer staging and management pathways were all recorded. The primary endpoint was all-cause mortality.

RESULTS

The total of 909 patients were examined. In the 29% who did not undergo resectional surgery, 6.5% had too little disease, 13.8% had too much disease, while 8.7% were deemed too frail. The highest two-year mortality was observed in the too much (83.2%) and too frail (75.9%) groups, whereas in patients with too little cancer the rate was 5.1%, and in those undergoing a resection it was 19.2% (P < 0.001).

CONCLUSIONS

The study has expectedly shown poor survival in the too much and too frail groups. We believe that understanding the prognosis in these subgroups is vital, as it informs complex decisions on whether to operate. Moreover, an overall reporting taking into account the proportion of these groups in an multidisciplinary team practice (the non-surgical index) is proposed to render individual surgeon's mortality results meaningful as a comparative measure.

Standards of practice in acute ischemic stroke intervention: International recommendations

This article was first published in JNIS. Cite this article as: Pierot L, Jayaraman MV, Szikora I, et al. Standards of practice in acute ischemic stroke intervention: international recommendations. Journal of NeuroInterventional Surgery. Published Online First: 28 August 2018. doi: 10.1136/neurintsurg-2018-014287.

eTICI reperfusion: defining success in endovascular stroke therapy

Background

Revascularization after endovascular therapy for acute ischemic stroke is measured by the Thrombolysis In Cerebral Infarction (TICI) scale, yet variability exists in scale definitions. We examined the degree of reperfusion with the expanded TICI (eTICI) scale and association with outcomes in the HERMES collaboration of recent endovascular trials.

Methods

The HERMES Imaging Core, blind to all other data, evaluated angiography after endovascular therapy in HERMES. A battery of TICI scores (mTICI, TICI, TICI2C) was used to define reperfusion of the initial target occlusion defined by non-invasive imaging and conventional angiography.

Results

Angiography of 801 subjects was available, including 797 defined by non-invasive imaging (154 internal carotid artery (ICA), 583 M1, 60 M2) and 748 by conventional angiography (195 ICA, 459 M1, 94 M2). Among 729 subjects in whom the reperfusion grade could be established, using eTICI (3=100%, 2C=90–99%, 2b67=67–89%, 2b50=50–66%) of the conventional angiography target occlusion, there were 63 eTICI 3 (9%), 166 eTICI 2c (23%), 218 eTICI 2b67 (30%), 103 eTICI 2b50 (14%), 100 eTICI 2a (14%), 19 eTICI 1 (3%), and 60 eTICI 0 (8%). Modified Rankin Scale shift analyses from baseline to 90 days showed that increasing TICI grades were linked with better outcomes, with significant distinctions between TICI 0/1 versus 2a (p=0.028), 2a versus 2b50 (p=0.017), and 2b50 versus 2b67 (p=0.014).

Conclusions

The benefit of endovascular therapy in HERMES was strongly associated with increasing degrees of reperfusion defined by eTICI. The eTICI metric identified meaningful distinctions in clinical outcomes and may be used in future studies and routine practice.

A global call to action to improve the care of people with fragility fractures

The ageing of society is driving an enormous increase in fragility fracture incidence and imposing a massive burden on patients, their families, health systems and societies globally. Disrupting the status quo has therefore become an obligation and a necessity. Initiated by the Fragility Fracture Network (FFN) at a "Presidents' Roundtable" during the 5th FFN Global Congress in 2016 several leading organisations agreed that a global multidisciplinary and multiprofessional collaboration, resulting in a Global Call to Action (CtA), would be the right step forward to improve the care of people presenting with fragility fractures. So far global and regional organisations in geriatrics/internal medicine, orthopaedics, osteoporosis/metabolic bone disease, rehabilitation and rheumatology were contacted as well as national organisations in five highly populated countries (Brazil, China, India, Japan and the United States), resulting in 81societies endorsing the CtA. We call for implementation of a systematic approach to fragility fracture care with the goal of restoring function and preventing subsequent fractures without further delay. There is an urgent need to improve: To address this fragility fracture crisis, the undersigned organisations pledge to intensify their efforts to improve the current management of all fragility fractures, prevent subsequent fractures, and strive to restore functional abilities and quality of life.

Tenecteplase versus Alteplase before Thrombectomy for Ischemic Stroke

BACKGROUND

Intravenous infusion of alteplase is used for thrombolysis before endovascular thrombectomy for ischemic stroke. Tenecteplase, which is more fibrin-specific and has longer activity than alteplase, is given as a bolus and may increase the incidence of vascular reperfusion.

METHODS

We randomly assigned patients with ischemic stroke who had occlusion of the internal carotid, basilar, or middle cerebral artery and who were eligible to undergo thrombectomy to receive tenecteplase (at a dose of 0.25 mg per kilogram of body weight; maximum dose, 25 mg) or alteplase (at a dose of 0.9 mg per kilogram; maximum dose, 90 mg) within 4.5 hours after symptom onset. The primary outcome was reperfusion of greater than 50% of the involved ischemic territory or an absence of retrievable thrombus at the time of the initial angiographic assessment. Noninferiority of tenecteplase was tested, followed by superiority. Secondary outcomes included the modified Rankin scale score (on a scale from 0 [no neurologic deficit] to 6 [death]) at 90 days. Safety outcomes were death and symptomatic intracerebral hemorrhage.

RESULTS

Of 202 patients enrolled, 101 were assigned to receive tenecteplase and 101 to receive alteplase. The primary outcome occurred in 22% of the patients treated with tenecteplase versus 10% of those treated with alteplase (incidence difference, 12 percentage points; 95% confidence interval [CI], 2 to 21; incidence ratio, 2.2; 95% CI, 1.1 to 4.4; P=0.002 for noninferiority; P=0.03 for superiority). Tenecteplase resulted in a better 90-day functional outcome than alteplase (median modified Rankin scale score, 2 vs. 3; common odds ratio, 1.7; 95% CI, 1.0 to 2.8; P=0.04). Symptomatic intracerebral hemorrhage occurred in 1% of the patients in each group.

CONCLUSIONS

Tenecteplase before thrombectomy was associated with a higher incidence of reperfusion and better functional outcome than alteplase among patients with ischemic stroke treated within 4.5 hours after symptom onset. (Funded by the National Health and Medical Research Council of Australia and others; EXTEND-IA TNK ClinicalTrials.gov number, NCT02388061 .).

Association of follow-up infarct volume with functional outcome in acute ischemic stroke: a pooled analysis of seven randomized trials

Background

Follow-up infarct volume (FIV) has been recommended as an early indicator of treatment efficacy in patients with acute ischemic stroke. Questions remain about the optimal imaging approach for FIV measurement.

Objective

To examine the association of FIV with 90-day modified Rankin Scale (mRS) score and investigate its dependency on acquisition time and modality.

Methods

Data of seven trials were pooled. FIV was assessed on follow-up (12 hours to 2 weeks) CT or MRI. Infarct location was defined as laterality and involvement of the Alberta Stroke Program Early CT Score regions. Relative quality and strength of multivariable regression models of the association between FIV and functional outcome were assessed. Dependency of imaging modality and acquisition time (≤48 hours vs >48 hours) was evaluated.

Results

Of 1665 included patients, 83% were imaged with CT. Median FIV was 41 mL (IQR 14–120). A large FIV was associated with worse functional outcome (OR=0.88(95% CI 0.87 to 0.89) per 10 mL) in adjusted analysis. A model including FIV, location, and hemorrhage type best predicted mRS score. FIV of ≥133 mL was highly specific for unfavorable outcome. FIV was equally strongly associated with mRS score for assessment on CT and MRI, even though large differences in volume were present (48 mL (IQR 15–131) vs 22 mL (IQR 8–71), respectively). Associations of both early and late FIV assessments with outcome were similar in strength (ρ=0.60(95% CI 0.56 to 0.64) and ρ=0.55(95% CI 0.50 to 0.60), respectively).

Conclusions

In patients with an acute ischemic stroke due to a proximal intracranial occlusion of the anterior circulation, FIV is a strong independent predictor of functional outcome and can be assessed before 48 hours, oneither CT or MRI.

Abstract TP222: Improving the Quality of Acute Stroke Care in regional Australia: The Victorian Stroke Telemedicine Program

Background: The Victorian Stroke Telemedicine (VST) program is the largest stroke telemedicine service operating in Australia. Patients and clinicians at 16 regional hospitals in Victoria are provided with 24/7/365 access to a network of on-call metropolitan-based neurologists via telemedicine. The VST program supports rapid differential diagnosis and enhances access to best-practice treatments for acute stroke, including transfer to comprehensive stroke centres for endovascular clot retrieval (ECR).

Method: A historical-controlled cohort design was used to evaluate the VST Program. At each hospital, consecutive patient-level data were obtained 12 months before the VST program commenced (pre) and during the first 12 months of implementing the program (post). Basic clinical data were collected for patients aged 18 years or more and arriving in the Emergency Department (ED) with suspected stroke. Detailed data collection on the patient journey in hospital was conducted for patients with a confirmed ischemic stroke who arrived within 4.5 hours of symptom onset. Aggregated descriptive statistics using the available data for 16 hospitals are presented.

Results: Overall, 6099 patients with suspected stroke (2932 pre, 3167 post) have presented up to 28/7/2017. Patients arriving to ED within 4.5 hours of ischemic stroke symptom onset: pre-VST n=358 (54% male; mean age 74 years) and post-VST n=484 (59% male, median age 76 years). The proportion of patients meeting these criteria who received intravenous thrombolysis increased (pre: 30% to post: 38%, p=0.019). The median door-to-needle time was faster (pre: 103 minutes; post: 72 minutes, p<0.001), and more patients received thrombolysis within 60 minutes of arrival (pre: 14%; post: 32%, p<0.001). Symptomatic intracerebral hemorrhage after thrombolysis was reduced (pre: 16%; post: 5%, p=0.002). Since the availability of ECR in May 2015, 25% of cases receiving thrombolysis were transferred for ECR.

Conclusion: Telemedicine expedites access to optimal stroke care and immediately facilitated access to the newest intervention, ECR, with more patients safely and efficiently treated.

Abstract 113: CT Perfusion Mismatch Identifies More Thrombectomy Patients Than Clinical Core Mismatch

Background: Following DAWN and DEFUSE 3, optimal imaging selection of large vessel ischemic stroke patients for thrombectomy >6h is important. We hypothesized that perfusion mismatch used in EXTEND-IA and DEFUSE 3 would identify more patients eligible for thrombectomy than clinical-core mismatch used in DAWN.

Methods: Prospectively collected data were analyzed for acute ischemic stroke patients aged>18 with pre-treatment whole brain CT perfusion from 2012-2017 at a comprehensive stroke center. CTP was omitted >6h in patients with extensive CT hypodensity. We compared the proportion of patients with anterior circulation large vessel occlusion (ICA, M1 and tandem occlusions) who fulfilled criteria for DAWN (clinical-core mismatch: age<80 & NIHSS≥20 with <51mL core, age<80 & NIHSS10-19 with <31mL core, age>80 & NIHSS>10 with<21mL core), DEFUSE3 (mismatch ratio>1.8, mismatch>15mL, core<70mL, age<91, NIHSS>5) and EXTEND-IA (mismatch ratio>1.2, mismatch>10mL, core<70mL, no age or NIHSS limits). Pre-morbid function, alteplase eligibility and tandem occlusion trial exclusions were not applied to emulate clinical practice. Independent functional outcome was defined as 90 day mRS 0-2.

Results: Of 982 ischemic stroke patients evaluated with pre-treatment CTP, 291 had large vessel occlusion. Within 6h of stroke onset, 175/231 (76%) patients met EXTEND-IA criteria compared to 153/231 (60%) DEFUSE3 and 96/231 (42%) DAWN, p<0.0001 for all comparisons. Beyond 6h after onset, 39/58 (67%) met EXTEND-IA mismatch criteria compared to 33/58 (57%) DEFUSE 3 criteria and 26/58 (45%) DAWN criteria, p<0.0001 for all comparisons. Overall 4 patients with clinical-core mismatch did not meet perfusion mismatch criteria. Patients eligible for DEFUSE3 but not DAWN achieved independence in 48% vs 40% in those eligible for both studies, OR 2.1 95%CI 0.9-5.0, p=0.09 in logistic regression adjusted for age and NIHSS. Similar findings applied to patients eligible for EXTEND-IA but not DAWN.

Conclusions: Perfusion mismatch selection would lead to substantially more patients receiving thrombectomy than clinical-core mismatch. These patients were generally older with milder NIHSS, but had similar probability of independent outcomes.

Abstract WMP17: Time to Treatment, Collaterals and Recanalization in Basilar Artery Occlusion: Which Factors Determine Prognosis?

Background: Whether radiological factors influence the effect of time to recanalization on outcome in basilar artery occlusion (BAO) is uncertain. We evaluated the association between onset time to treatment (OTT), radiological prognostic factors (presence of collaterals and extent of the occlusion) and clinical outcome in endovascular BAO patients.

Methods: Clinical and radiological data of consecutive endovascular-treated stroke patients with BAO diagnosed on CT angiography at Royal Melbourne Hospital (Australia), Royal Adelaide Hospital (Australia), University Hospital of Tor Vergata (Rome, Italy) and from the international BASICS registry were retrospectively analysed. The Basilar Artery on Computed Tomography Angiography (BATMAN) score and Posterior Circulation Collateral Score (PC-CS) were assessed by two investigators blinded to clinical outcome. Previously validated dichotomies for favorable BATMAN score (≥7) or PC-CS (≥6) were used. Good outcome was defined as modified Rankin Scale≤3 within 3 months; successful reperfusion as mTICI 2b-3 (or TIMI 2-3 in BASICS).

Results: We included 155 BAO patients treated with intra-arterial urokinase and/or mechanical thrombectomy (86 with mechanical thrombectomy): mean(SD) age 65(14), median NIHSS 22 (IQR 12-30), median OTT 348.5 min [(IQR 246-480), 37% treated beyond 6hours]. In logistic regression adjusted for age and NIHSS, OTT>6h was associated with poor outcome (OR 3.0, 95%CI 1.4-6.6, p=0.006) but this association was only present in the subgroup with unfavourable BATMAN score (adjusted OR 4.6, 95%CI 1.7-12, p=0.002) or PC-CS (3.7, 95%CI 1.3-11, p=0.02) and not in those with favorable BATMAN score (adjusted OR 0.7, 95%CI 0.2-3.6, p=0.7) or PC-CS (2.7, 95%CI 0.6-12, p=0.2). When successful reperfusion was added to the model with age and NIHSS, OTT>6h remained significantly associated with poor outcome in patients with unfavorable BATMAN score (OR 5.0, 95%CI 1.8-14, p=0.002) or PC-CS (4.5, 95%CI 1.4-14, p=0.01), but not in patients with favorable BATMAN score (OR 1.6, 95%CI 0.2-13, p=0.6) or PC-CS (3.2, 95%CI 0.6-17, p=0.2).

Conclusions: BAO patients with good collaterals and less extensive occlusion may have good outcome if recanalization is achieved even in a delayed time window.

Endovascular Thrombectomy for Ischemic Stroke Increases Disability-Free Survival, Quality of Life, and Life Expectancy and Reduces Cost

Background

Endovascular thrombectomy improves functional outcome in large vessel occlusion ischemic stroke. We examined disability, quality of life, survival and acute care costs in the EXTEND-IA trial, which used CT-perfusion imaging selection.

Methods

Large vessel ischemic stroke patients with favorable CT-perfusion were randomized to endovascular thrombectomy after alteplase versus alteplase-only. Clinical outcome was prospectively measured using 90-day modified Rankin scale (mRS). Individual patient expected survival and net difference in Disability/Quality-adjusted life years (DALY/QALY) up to 15 years from stroke were modeled using age, sex, 90-day mRS, and utility scores. Level of care within the first 90 days was prospectively measured and used to estimate procedure and inpatient care costs (US$ reference year 2014).

Results

There were 70 patients, 35 in each arm, mean age 69, median NIHSS 15 (IQR 12–19). The median (IQR) disability-weighted utility score at 90 days was 0.65 (0.00–0.91) in the alteplase-only versus 0.91 (0.65–1.00) in the endovascular group (p = 0.005). Modeled life expectancy was greater in the endovascular versus alteplase-only group (median 15.6 versus 11.2 years, p = 0.02). The endovascular thrombectomy group had fewer simulated DALYs lost over 15 years [median (IQR) 5.5 (3.2–8.7) versus 8.9 (4.7–13.8), p = 0.02] and more QALY gained [median (IQR) 9.3 (4.2–13.1) versus 4.9 (0.3–8.5), p = 0.03]. Endovascular patients spent less time in hospital [median (IQR) 5 (3–11) days versus 8 (5–14) days, p = 0.04] and rehabilitation [median (IQR) 0 (0–28) versus 27 (0–65) days, p = 0.03]. The estimated inpatient costs in the first 90 days were less in the thrombectomy group (average US$15,689 versus US$30,569, p = 0.008) offsetting the costs of interhospital transport and the thrombectomy procedure (average US$10,515). The average saving per patient treated with thrombectomy was US$4,365.

Conclusion

Thrombectomy patients with large vessel occlusion and salvageable tissue on CT-perfusion had reduced length of stay and overall costs to 90 days. There was evidence of clinically relevant improvement in long-term survival and quality of life.

Clinical Trial Registration

http://www.ClinicalTrials.gov NCT01492725 (registered 20/11/2011).

Cerebral blood volume lesion extent predicts functional outcome in patients with vertebral and basilar artery occlusion

Background

CT perfusion may improve diagnostic accuracy in posterior circulation stroke. The posterior circulation Acute Stroke Prognosis Early CT score (pc-ASPECTS) on Computed Tomography Angiography source images (CTA-SI) predicts functional outcome in patients with basilar artery occlusion.

Aims

We assessed the prognostic value of pc-ASPECTS on CT perfusion in patients with vertebral and basilar artery occlusion (VBAO) in comparison with CTA-SI.

Methods

Whole-brain CT perfusion from consecutive stroke patients with VBAO at four stroke centers was retrospectively analyzed. pc-ASPECTS – a 10-point score assessing hypoattenuation on CTA-SI – was calculated from CT perfusion parameters as focally reduced cerebral blood flow or cerebral blood volume, focally increased time to peak of the deconvolved tissue residue function (Tmax) or mean transit time. Two investigators independently reviewed the images. Reliability was assessed with intraclass correlation coefficient. Good outcome was defined as modified Rankin scale ≤3 at three months.

Results

We included 60 patients with VBAO. After assessment of four CT perfusion maps simultaneously, area-under-ROC curve (AROC) was 0.83 (95%CI 0.72–0.93) for cerebral blood volume, 0.76 (95%CI 0.64–0.89) for cerebral blood flow, 0.77 (95%CI 0.64–0.89) for Tmax, 0.70 (95%CI 0.56–0.84) for mean transit time versus area-under-ROC curve 0.64 (95%CI 0.50–0.79) for CTA-SI. Cerebral blood volume had greater accuracy compared with CTA-SI for poor outcome (p = 0.04). In logistic regression analysis, cerebral blood volume pc-ASPECTS≤8 was independently associated with poor outcome (OR 9.3 95%CI 2.2–41; p = 0.003, adjusted for age and clinical severity). Inter-rater agreement was substantial for cerebral blood volume pc-ASPECTS (intraclass correlation coefficient 0.82 95%CI 0.71–0.90 versus 0.67 for CTA-SI 95%CI 0.43–0.81).

Conclusions

Cerebral blood volume pc-ASPECTS may identify VBAO patients at higher risk of disability.

Tenecteplase versus alteplase before endovascular thrombectomy (EXTEND-IA TNK): A multicenter, randomized, controlled study

Background and hypothesis Intravenous thrombolysis with alteplase remains standard care prior to thrombectomy for eligible patients within 4.5 h of ischemic stroke onset. However, alteplase only succeeds in reperfusing large vessel arterial occlusion prior to thrombectomy in a minority of patients. We hypothesized that tenecteplase is non-inferior to alteplase in achieving reperfusion at initial angiogram, when administered within 4.5 h of ischemic stroke onset, in patients planned to undergo endovascular therapy. Study design EXTEND-IA TNK is an investigator-initiated, phase II, multicenter, prospective, randomized, open-label, blinded-endpoint non-inferiority study. Eligibility requires a diagnosis of ischemic stroke within 4.5 h of stroke onset, pre-stroke modified Rankin Scale≤3 (no upper age limit), large vessel occlusion (internal carotid, basilar, or middle cerebral artery) on multimodal computed tomography and absence of contraindications to intravenous thrombolysis. Patients are randomized to either IV alteplase (0.9 mg/kg, max 90 mg) or tenecteplase (0.25 mg/kg, max 25 mg) prior to thrombectomy. Study outcomes The primary outcome measure is reperfusion on the initial catheter angiogram, assessed as modified treatment in cerebral infarction 2 b/3 or the absence of retrievable thrombus. Secondary outcomes include modified Rankin Scale at day 90 and favorable clinical response (reduction in National Institutes of Health Stroke Scale by ≥8 points or reaching 0-1) at day 3. Safety outcomes are death and symptomatic intracerebral hemorrhage. Trial registration ClinicalTrials.gov NCT02388061.

Mind the (treatment) gap: a global perspective on current and future strategies for prevention of fragility fractures

This narrative review considers the key challenges facing healthcare professionals and policymakers responsible for providing care to populations in relation to bone health. These challenges broadly fall into four distinct themes: (1) case finding and management of individuals at high risk of fracture, (2) public awareness of osteoporosis and fragility fractures, (3) reimbursement and health system policy and (4) epidemiology of fracture in the developing world. Findings from cohort studies, randomised controlled trials, systematic reviews and meta-analyses, in addition to current clinical guidelines, position papers and national and international audits, are summarised, with the intention of providing a prioritised approach to delivery of optimal bone health for all. Systematic approaches to case-finding individuals who are at high risk of sustaining fragility fractures are described. These include strategies and models of care intended to improve case finding for individuals who have sustained fragility fractures, those undergoing treatment with medicines which have an adverse effect on bone health and people who have diseases, whereby bone loss and, consequently, fragility fractures are a common comorbidity. Approaches to deliver primary fracture prevention in a clinically effective and cost-effective manner are also explored. Public awareness of osteoporosis is low worldwide. If older people are to be more pro-active in the management of their bone health, that needs to change. Effective disease awareness campaigns have been implemented in some countries but need to be undertaken in many more. A major need exists to improve awareness of the risk that osteoporosis poses to individuals who have initiated treatment, with the intention of improving adherence in the long term. A multisector effort is also required to support patients and their clinicians to have meaningful discussions concerning the risk-benefit ratio of osteoporosis treatment. With regard to prioritisation of fragility fracture prevention in national policy, there is much to be done. In the developing world, robust epidemiological estimates of fracture incidence are required to inform policy development. As the aging of the baby boomer generation is upon us, this review provides a comprehensive analysis of how bone health can be improved worldwide for all.

Abstract WP53: The prognostic value of Posterior Circulation Acute Stroke Prognosis Early Ct Score (pcaspects) on CT perfusion in patients with basilar artery occlusion

Background: CT perfusion (CTP) increases diagnostic confidence in ischaemic stroke. Despite bone-related artefacts, CTP has been shown to improve diagnostic sensitivity compared to non contrast-CT (NCCT) and Computed Tomography Angiography source images (CTA-SI) in posterior circulation strokes. The posterior circulation Acute Stroke Prognosis Early CT score (pcASPECTS) on CTA-SI predicts clinical outcome in patients with basilar artery occlusion (BAO). We assessed the prognostic value of pcASPECTS on CTP in BAO patients.

Methods: A retrospective analysis of consecutive patients with BAO diagnosed on CT angiography was performed. pcASPECTS was assessed as evident hypoattenuation on CTA-SI, focally reduced cerebral blood flow (CBF) or cerebral blood volume (CBV), focally increased time to peak of the residue function (Tmax) or mean transit time (MTT). Two investigators independently reviewed the images blinded to clinical outcome. Reliability was assessed with intraclass correlation coefficient (ICC). Good outcome was defined as modified Rankin Scale≤3 at 3 months.

Results: We included 43 BAO patients with whole-brain CTP images. In receiver-operating-characteristic (ROC) analysis, the area-under-curve (AUC) was 0.79 (95% CI 0.6-0.9) for pcASPECTS on CBF, 0.77 (95% CI 0.6-0.9) on Tmax, 0.73 (95% CI 0.6-0.9) on MTT, 0.72 (95% CI 0.6-0.9) on CBV, 0.67 (95% CI 0.5-0.8) on CTA-SI. In logistic regression adjusted for age and clinical severity, pcASPECTS<8 was associated with poor outcome on Tmax (OR 14.6, 95% CI 2.3-115; p=0.007) and CBF (OR 15.1, 95% CI 1.3-121; p=0.02). Although CTP AUC did not show higher accuracy in comparison with CTA-SI AUC (p=0.2), in logistic regression, CTA-SI pcASPECTS was not significantly associated with clinical outcome (OR 6.9, 95% CI 0.7-70; p=0.1, adjusted for age, NHSS). Higher pcASPECTS on CBF (OR 0.5 95%CI 0.2-0.9, p=0.04) and Tmax (OR 0.5 95% 0.3-0.9; p=0.02) were associated with lower mortality. Interrater reliability was good for CTP maps (ICC between 0.74 and 0.86 95% CI

0.6-0.9 versus 0.66 for CTA-SI 95% CI 0.4-0.8).

Conclusions: The CTP pcASPECTS may identify BAO patients at higher risk of disability and mortality.

Abstract 176: HERMES: Collaterals at Angiography Guide Clinical Outcomes

Background: Collateral circulation is a key factor in the pathophysiology of ischemic stroke. We conducted detailed analyses of angiography acquired immediately prior to endovascular therapy in the HERMES collaboration of recent landmark thrombectomy trials to determine predictors of collateral status and assess impact on clinical outcomes.

Methods: The HERMES Imaging Core, blind to all other clinical and imaging data, independently interpreted conventional angiography acquired immediately prior to endovascular therapy. Collaterals were graded with the ASITN scale, based on available data for the site of arterial occlusion defined on initial injections. The statistical core analyzed the association of collateral grade with demographics, baseline NIHSS, site of arterial occlusion and clinical outcomes of day 90 mRS.

Results: Angiography of collaterals was available in 376/605 (62%), including ASITN grades 0 in 7 (2%), 1 in 40 (10%), 2 in 182 (48%), 3 in 129 (34%) and 4 in 18 (5%). Elevated blood glucose (p=0.011) and diabetes (p=0.048) were associated with worse collateral grades, but age and NIHSS were unrelated. Better collateral grade was strongly associated with the degree of subsequent TICI reperfusion (p<0.001). The limited numbers of symptomatic intracranial hemorrhage (14/376 or 3.7%) or parenchymal hematomas (18/376 or 4.8%) precluded analysis of association with collateral status. Collaterals had strong impact on mRS shift from baseline to 90 days (p<0.001).

Multivariable regression revealed that better collateral status was a potent determinant (OR 1.37 per grade, p=0.028) of outcomes, equivalent to 4.5 points of NIHSS and 14 years of age in terms of impact on mRS outcomes.

Conclusions: Collaterals at angiography were a potent determinant of clinical outcomes in recent landmark thrombectomy trials.

Abstract 128: TICI Reperfusion in HERMES: Success in Endovascular Stroke Therapy

Background: Successful revascularization after endovascular therapy for acute ischemic stroke is measured by TICI score, yet variability exists in scale definitions and use. We examined the degree of reperfusion and association with outcomes in the HERMES collaboration of recent endovascular trials.

Methods: An independent reader of the HERMES Imaging Core, blind to all other data, evaluated the angiography of subjects treated with endovascular therapy in HERMES. A battery of various TICI scores (mTICI, oTICI, oTICI2C) was used to define reperfusion of the initial target occlusion on noninvasive imaging (ITO) and conventional angiography (CATO). Statistical analyses examined all TICI reperfusion metrics and correlation with clinical outcomes.

Results: Angiography of 593 subjects was analyzed, including ITO (124 ICA, 413 M1, 47 M2) and CATO (161 ICA, 329 M1, 62 M2). Across the entire scale range (0-3), the mTICI (AUC 0.61), oTICI (AUC 0.61) and oTICI2C (AUC 0.62) revealed similar ROC characteristics (p=0.450) in discriminating that more reperfusion is associated with better clinical outcomes. Using oTICI2C (3=100%, 2C=90-99%, o2B=67-89%, m2B=50-66%) of CATO, there were 44 TICI 3 (8%), 125 TICI 2C (22%), 178 TICI o2B (32%), 80 TICI m2B (14%), 85 TICI 2A (15%), 15 TICI 1 (3%) and 35 TICI 0 (6%). mRS shift analyses from baseline to 90 days revealed increasing TICI grades were linked with better outcomes (Figure), with significant distinctions of m2B vs. 2C (p=0.023) and all 2B combined vs. 3 (p=0.045).

Conclusions: The benefit of endovascular therapy in HERMES was strongly associated with increasing degrees of TICI reperfusion. The oTICI2C metric reveals important distinctions in clinical outcomes that should be used in future studies.

Abstract 29: The Association Between General Anesthesia and Outcome of Endovascular Thrombectomy in Pooled Data From Five Randomized Trials

Background and purpose: General anesthesia (GA) during endovascular thrombectomy has been associated with worse patient outcomes in observational studies. We examined the association between GA and thrombectomy outcomes in pooled data from five randomized trials.

Methods: Patient-level data were pooled from trials comparing endovascular thrombectomy (predominantly using stent retrievers) with standard care in anterior circulation ischemic stroke patients (HERMES Collaboration): MR CLEAN, ESCAPE, REVASCAT, SWIFT PRIME, and EXTEND IA. The primary outcome was ordinal analysis of modified Rankin scale (mRS) at 90 days in the GA and non-GA subgroups, adjusted for baseline prognostic variables. To account for between-trial variance we used mixed-effects modeling with a random effect for trial incorporated in all models.

Results: Of 1287 patients, 634 were allocated to endovascular thrombectomy and general anesthesia was used in 153/609 (25%) of endovascular-treated patients with anesthesia information available. Although dysphasic patients are sometimes felt to be less co-operative and require GA, the rate of GA was 25% in both right and left hemisphere patients. At baseline, GA and non-GA patients had similar age, NIHSS and time to randomization. Endovascular thrombectomy was associated with increased odds of improved functional outcome at 3 months, regardless of whether GA (cOR 1.73 95%CI 1.10-2.72, p=0.02) or non-GA (cOR 2.61 95%CI 2.01-3.40, p<0.001) was used. The odds of improved outcome were, however, significantly greater for those treated under non-GA (OR 1.59 95%CI 1.12-2.26, p=0.01). Pneumonia was more common in the GA group (16% vs 9% p=0.03). Rates of vessel perforation were similar in GA (0.7%) vs non-GA patients (1.8%, p=0.52). Delay between randomization and reperfusion was greater in GA versus non-GA patients (median 98 vs 75 min, p<0.001).

Conclusions: Worse outcomes after endovascular thrombectomy were associated with GA, after adjustment for baseline prognostic variables. These data support avoidance of GA whenever possible. The procedure did, however, remain effective versus standard care in patients treated under GA, indicating that treatment is still worthwhile in those who require anesthesia for medical reasons.