PRERISK: A Personalized, Artificial Intelligence-Based and Statistically-Based Stroke Recurrence Predictor for Recurrent Stroke

BACKGROUND

Predicting stroke recurrence for individual patients is difficult, but individualized prediction may improve stroke survivors' engagement in self-care. We developed PRERISK: a statistical and machine learning classifier to predict individual risk of stroke recurrence.

METHODS

We analyzed clinical and socioeconomic data from a prospectively collected public health care-based data set of 41 975 patients admitted with stroke diagnosis in 88 public health centers over 6 years (2014-2020) in Catalonia-Spain. A new stroke diagnosis at least 24 hours after the index event was considered as a recurrent stroke, which was considered as our outcome of interest. We trained several supervised machine learning models to provide individualized risk over time and compared them with a Cox regression model. Models were trained to predict early, late, and long-term recurrence risk, within 90, 91 to 365, and >365 days, respectively. C statistics and area under the receiver operating characteristic curve were used to assess the accuracy of the models.

RESULTS

Overall, 16.21% (5932 of 36 114) of patients had stroke recurrence during a median follow-up of 2.69 years. The most powerful predictors of stroke recurrence were time from previous stroke, Barthel Index, atrial fibrillation, dyslipidemia, age, diabetes, and sex, which were used to create a simplified model with similar performance, together with modifiable vascular risk factors (glycemia, body mass index, high blood pressure, cholesterol, tobacco dependence, and alcohol abuse). The areas under the receiver operating characteristic curve were 0.76 (95% CI, 0.74-0.77), 0.60 (95% CI, 0.58-0.61), and 0.71 (95% CI, 0.69-0.72) for early, late, and long-term recurrence risk, respectively. The areas under the receiver operating characteristic curve of the Cox risk class probability were 0.73 (95% CI, 0.72-0.75), 0.59 (95% CI, 0.57-0.61), and 0.67 (95% CI, 0.66-0.70); machine learning approaches (random forest and AdaBoost) showed statistically significant improvement (P<0.05) over the Cox model for the 3 recurrence time periods. Stroke recurrence curves can be simulated for each patient under different degrees of control of modifiable factors.

CONCLUSIONS

PRERISK is a novel approach that provides a personalized and fairly accurate risk prediction of stroke recurrence over time. The model has the potential to incorporate dynamic control of risk factors.

Enhancing blood pressure management protocol implementation in patients with acute intracerebral haemorrhage through a nursing-led approach: A retrospective cohort study

AIM

To evaluate the impact of nurse care changes in implementing a blood pressure management protocol on achieving rapid, intensive and sustained blood pressure reduction in acute intracerebral haemorrhage patients.

DESIGN

Retrospective cohort study of prospectively collected data over 6 years.

METHODS

Intracerebral haemorrhage patients within 6 h and systolic blood pressure ≥ 150 mmHg followed a rapid (starting treatment at computed tomography suite with a target achievement goal of ≤60 min), intensive (target systolic blood pressure < 140 mmHg) and sustained (maintaining target stability for 24 h) blood pressure management plan. We differentiated six periods: P1, stroke nurse at computed tomography suite (baseline period); P2, antihypertensive titration by stroke nurse; P3, retraining by neurologists; P4, integration of a stroke advanced practice nurse; P5, after COVID-19 impact; and P6, retraining by stroke advanced practice nurse. Outcomes included first-hour target achievement (primary outcome), tomography-to-treatment and treatment-to-target times, first-hour maximum dose of antihypertensive treatment and 6-h and 24-h systolic blood pressure variability.

RESULTS

Compared to P1, antihypertensive titration by stroke nurses (P2) reduced treatment-to-target time and increased the rate of first-hour target achievement, retraining of stroke nurses by neurologists (P3) maintained a higher rate of first-hour target achievement and the integration of a stroke advanced practice nurse (P4) reduced both 6-h and 24-h systolic blood pressure variability. However, 6-h systolic blood pressure variability increased from P4 to P5 following the impact of the COVID-19 pandemic. Finally, compared to P1, retraining of stroke nurses by stroke advanced practice nurse (P6) reduced tomography-to-treatment time and increased the first-hour maximum dose of antihypertensive treatment.

CONCLUSION

Changes in nursing care and continuous education can significantly enhance the time metrics and blood pressure outcomes in acute intracerebral haemorrhage patients.

REPORTING METHOD

STROBE guidelines.

PATIENT AND PUBLIC CONTRIBUTION

No Patient or Public Contribution.

Exploratory study of blood biomarkers in patients with post-stroke epilepsy

INTRODUCTION

In addition to clinical factors, blood-based biomarkers can provide useful information on the risk of developing post-stroke epilepsy (PSE). Our aim was to identify serum biomarkers at stroke onset that could contribute to predicting patients at higher risk of PSE.

PATIENTS AND METHODS

From a previous study in which 895 acute stroke patients were followed-up, 51 patients developed PSE. We selected 15 patients with PSE and 15 controls without epilepsy. In a biomarker discovery setting, 5 Olink panels of 96 proteins each, were used to determine protein levels. Biomarkers that were down-regulated and overexpressed in PSE patients, and those that showed the strongest interactions with other proteins were validated using an enzyme-linked immunosorbent assay in samples from 50 PSE patients and 50 controls. A ROC curve analysis was used to evaluate the predictive ability of significant biomarkers to develop PSE.

RESULTS

Mean age of the PSE discovery cohort was 68.56 ± 15.1, 40% women and baseline NIHSS 12 [IQR 1-25]. Nine proteins were down-expressed: CASP-8, TNFSF-14, STAMBP, ENRAGE, EDA2R, SIRT2, TGF-alpha, OSM and CLEC1B. VEGFa, CD40 and CCL4 showed greatest interactions with the remaining proteins. In the validation analysis, TNFSF-14 was the single biomarker showing statistically significant downregulated levels in PSE patients (p = 0.006) and it showed a good predictive capability to develop PSE (AUC 0.733, 95% CI 0.601-0.865).

DISCUSSION AND CONCLUSION

Protein expression in PSE patients differs from that of non-epileptic stroke patients, suggesting the involvement of several different proteins in post-stroke epileptogenesis. TNFSF-14 emerges as a potential biomarker for predicting PSE.

Radial Versus Femoral Access for Mechanical Thrombectomy in Patients With Stroke: A Noninferiority Randomized Clinical Trial

BACKGROUND

Transfemoral access is predominantly used for mechanical thrombectomy in patients with stroke with a large vessel occlusion. Following the interventional cardiology guidelines, routine transradial access has been proposed as an alternative, although its safety and efficacy remain controversial. We aim to explore the noninferiority of radial access in terms of final recanalization.

METHODS

The study was an investigator-initiated, single-center, evaluator-blinded, noninferiority randomized clinical trial. Patients with stroke undergoing mechanical thrombectomy, with a patent femoral artery and a radial artery diameter ≥2.5 mm, were randomly assigned (1:1) to either transradial (60 patients) or transfemoral access (60 patients). The primary binary outcome was the successful recanalization (expanded Treatment in Cerebral Ischemia score, 2b-3) assigned by blinded evaluators. We established a noninferiority margin of -13.2%, considering an acceptable reduction of 15% in the expected recanalization rates.

RESULTS

From September 2021 to July 2023, 120 patients were randomly assigned and 116 (58 transradial access and 58 transfemoral access) with confirmed intracranial occlusion on the initial angiogram were included in the intention-to-treat analysis. Successful recanalization was achieved in 51 (87.9%) patients assigned to transfemoral access and in 56/58 (96.6%) patients assigned to transradial (adjusted 1 side risk difference [RD], -5.0% [95% CI, -6.61% to +13.1%]) showing noninferiority of transradial access. Median time from angiosuite arrival to first pass (femoral, 30 [interquartile range, 25-37] minutes versus radial: 41 [interquartile range, 33-62] minutes; P<0.001) and from angiosuite arrival to recanalization (femoral: 42 (IQR, 28-74) versus radial: 59.5 (IQR, 44-81) minutes; P<0.050) were longer in the transradial access group. Both groups presented 1 severe access complication and there was no difference in the rate of access conversion: transradial 7 (12.1%) versus transfemoral 5 (8.6%) (P=0.751).

CONCLUSIONS

Among patients who underwent mechanical thrombectomy, transradial access was noninferior to transfemoral access in terms of final recanalization. Procedural delays may favor transfemoral access as the default first-line approach.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT05225636.

Acute management of cerebral venous thrombosis: Indications, technique, and outcome of endovascular treatment in two high-volume centers

INTRODUCTION

After several uncontrolled studies and one randomized clinical trial, there is still uncertainty regarding the role of endovascular treatment (EVT) in cerebral venous thrombosis (CVT). This study aims to describe and assess different acute management strategies in the treatment of CVT.

METHODS

We performed a retrospective analysis of an international two-center registry of CVT patients admitted since 2019. Good outcome was defined as a return to baseline modified Rankin scale at three months. We described and compared EVT versus no-EVT patients.

RESULTS

We included 61 patients. Only one did not receive systemic anticoagulation. EVT was performed in 13/61 (20%) of the cases, with a median time from diagnosis to puncture of 4.5 h (1.25-28.5). EVT patients had a higher median baseline NIHSS [6 (IQR 2-17) vs 0 (0-2.7), p = 0.002)] and a higher incidence of intracerebral hemorrhage (53.8% vs 20.3%, p = 0.03). Recanalization was achieved in 10/13 (77%) patients. Thrombectomy was performed in every case with angioplasty in 7 out of 12 patients and stenting in 3 cases. No postprocedural complication was reported. An improvement of the median NIHSS from baseline to discharge [6 (2-17) vs 1(0-3.75); p < 0.001] was observed in EVT group. A total of 31/60 patients (50.8%) had good outcomes. Adjusting to NIHSS and ICH, EVT had a non-significant increase in the odds of a good outcome [aOR 1.42 (95%CI 0.73-2.8, p = 0.307)].

CONCLUSIONS

EVT in combination with anticoagulation was safe in acute treatment of CVT as suggested by NIHSS improvement. Selected patients may benefit from this treatment.

Stroke-associated pneumonia according to mCDC criteria: impact on prognosis and antibiotic therapy

Objective

The modified Centers for Disease Control and Prevention (mCDC) criteria have been proposed for diagnosing and managing stroke-associated pneumonia (SAP). The objective was to investigate the impact of SAP on stroke outcome depending on whether or not it conforms to mCDC criteria. Our secondary objective was to identify the responsible factors for antibiotic initiation in stroke patients.

Methods

We conducted a prospective, multicenter, observational study of ischemic stroke patients with moderate to severe stroke (NIHSS≥4) admitted within 24 h. For 7 days, mCDC criteria were assessed daily, and infections and antibiotics were recorded. Pneumonias were divided into those fulfilling mCDC criteria (mCDC-SAP) or not (other pneumonias, OPn). The effect of each type of pneumonia on 3-month outcome was evaluated in separated logistic regression models. Factors associated with antibiotic initiation were explored using a random forest analysis.

Results

Of the 342 patients studied, infections were diagnosed in 72 (21.6%), including 39 (11.7%) cases of pneumonia. Of them, 25 (7.5%) fulfilled mCDC criteria. Antibiotics were used in 92% of mCDC-SAP and 64.3% of OPn. In logistic regression analysis, mCDC-SAP, but not OPn, was an independent predictor of poor outcome [OR, 4.939 (1.022-23.868)]. The random forest analysis revealed that fever had the highest importance for antibiotic initiation.

Interpretation

The mCDC criteria might be useful for detecting clinically relevant SAP, which is associated with poor outcomes. Isolated signs of infection were more important for antibiotic initiation than compliance with pre-defined criteria. Therefore, adherence to mCDC criteria might result in antibiotic saving without compromising clinical outcome.

Clinico-radiological features of intracranial atherosclerosis-related large vessel occlusion prior to endovascular treatment

The identification of large vessel occlusion with underlying intracranial atherosclerotic disease (ICAS-LVO) before endovascular treatment (EVT) continues to be a challenge. We aimed to analyze baseline clinical-radiological features associated with ICAS-LVO that could lead to a prompt identification. We performed a retrospective cross-sectional study of consecutive patients with stroke treated with EVT from January 2020 to April 2022. We included anterior LVO involving intracranial internal carotid artery and middle cerebral artery. We analyzed baseline clinical and radiological variables associated with ICAS-LVO and evaluated the diagnostic value of a multivariate logistic regression model to identify ICAS-LVO before EVT. ICAS-LVO was defined as presence of angiographic residual stenosis or a trend to re-occlusion during EVT procedure. A total of 338 patients were included in the study. Of them, 28 patients (8.3%) presented with ICAS-LVO. After adjusting for confounders, absence of atrial fibrillation (OR 9.33, 95% CI 1.11-78.42; p = 0.040), lower hypoperfusion intensity ratio (HIR [Tmax > 10 s/Tmax > 6 s ratio], (OR 0.69, 95% CI 0.50-0.95; p = 0.025), symptomatic intracranial artery calcification (IAC, OR .15, 95% CI 1.64-26.42, p = 0.006), a more proximal occlusion (ICA, MCA-M1: OR 4.00, 95% CI 1.23-13.03; p = 0.021), and smoking (OR 2.91, 95% CI 1.08-7.90; p = 0.035) were associated with ICAS-LVO. The clinico-radiological model showed an overall well capability to identify ICAS-LVO (AUC = 0.88, 95% CI 0.83-0.94; p < 0.001). In conclusion, a combination of clinical and radiological features available before EVT can help to identify an ICAS-LVO. This approach could be useful to perform a rapid assessment of underlying etiology and suggest specific pathophysiology-based measures. Prospective studies are needed to validate these findings in other populations.

Combined technique as first approach in mechanical thrombectomy: Efficacy and safety of REACT catheter combined with stent retriever

INTRODUCTION

Mechanical thrombectomy (MT) with combined treatment including both a stent retriever and distal aspiration catheter may improve recanalization rates in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO). Here, we evaluated the effectiveness and safety of the REACT aspiration catheter used with a stent retriever.

METHODS

This prospective study included consecutive adult patients who underwent MT with a combined technique using REACT 68 and/or 71 between June 2020 and July 2021. The primary endpoints were final and first pass mTICI 2b-3 and mTICI 2c-3 recanalization. Analysis was performed after first pass and after each attempt. Secondary safety outcomes included procedural complications, symptomatic intracranial hemorrhage (sICH) at 24 h, in-hospital mortality, and 90-day functional independence (modified Rankin Scale [mRS] 0-2).

RESULTS

A total of 102 patients were included (median age 78; IQR: 73-87; 50.0% female). At baseline, median NIHSS score was 19 (IQR: 11-21), and ASPECTS was 9 (IQR: 8-10). Final mTICI 2b-3 recanalization was achieved in 91 (89.2%) patients and mTICI 2c-3 was achieved in 66 (64.7%). At first pass, mTICI 2b-3 was achieved in 55 (53.9%) patients, and mTICI 2c-3 in 37 (36.3%). The rate of procedural complications was 3.9% (4/102), sICH was 6.8% (7/102), in-hospital mortality was 12.7% (13/102), and 90-day functional independence was 35.6% (36/102).

CONCLUSION

A combined MT technique using a stent retriever and REACT catheter resulted in a high rate of successful recanalization and first pass recanalization in a sample of consecutive patients with AIS due to LVO in clinical use.

Exploring sex differences for acute ischemic stroke clinical, imaging and thrombus characteristics in the INTERRSeCT study

Women, especially following menopause, are known to have worse outcomes following acute ischemic stroke. One primary postulated biological mechanism for worse outcomes in older women is a reduction in the vasculoprotective effects of estrogen. Using the INTERRseCT cohort, a multicentre international observational cohort studying recanalization in acute ischemic stroke, we explored the effects of sex, and modifying effects of age, on neuroradiological predictors of recanalization including robustness of leptomeningeal collaterals, thrombus burden and thrombus permeability. Ordinal regression analyses were used to examine the relationship between sex and each of the neuroradiological markers. Further, we explored both multiplicative and additive interactions between age and sex. All patients (n = 575) from INTERRseCT were included. Mean age was 70.2 years (SD: 13.1) and 48.5% were women. In the unadjusted model, female sex was associated with better collaterals (OR 1.37, 95% CIs: 1.01-1.85), however this relationship was not significant after adjusting for age and relevant comorbidities. There were no significant interactions between age and sex. In a large prospective international cohort, we found no association between sex and radiological predictors of recanalization including leptomeningeal collaterals, thrombus permeability and thrombus burden.

Derivation and validation of three intracerebral hemorrhage expansion scores using different CT modalities

OBJECTIVES

To derivate and validate three scores for the prediction of intracerebral hemorrhage (ICH) expansion depending on the use of non-contrast CT (NCCT), single-phase CTA, or multiphase CTA markers of hematoma expansion, and to evaluate the added value of single-phase and multiphase CTA over NCCT.

METHODS

After prospectively deriving NCCT, single-phase CTA, and multiphase CTA hematoma expansion scores in 156 patients with ICH < 6 h, we validated them in 120 different patients. Discrimination and calibration of the three scores was assessed. Primary outcome was substantial hematoma expansion > 6 mL or > 33% at 24 h.

RESULTS

The evaluation of single-phase and multiphase CTA markers gave a steadily increase in discrimination for substantial hematoma expansion over NCCT markers. The C-index (95% confidence interval) in derivation and validation cohorts was 0.69 (0.58-0.80) and 0.59 (0.46-0.72) for NCCT score, significantly lower than 0.75 ([0.64-0.87], p = 0.038) and 0.72 ([0.59-0.84], p = 0.016) for single-phase CTA score, and than 0.79 ([0.68-0.89], p = 0.033) and 0.73 ([0.62-0.85], p = 0.031) for multiphase CTA score, respectively. The three scores showed good calibration in both derivation and validation cohorts: NCCT (χ2 statistic 0.389, p = 0.533; and χ2 statistic 0.352, p = 0.553), single-phase CTA (χ2 statistic 2.052, p = 0.359; and χ2 statistic 2.230, p = 0.328), and multiphase CTA (χ2 statistic 0.559, p = 0.455; and χ2 statistic 0.020, p = 0.887) scores, respectively.

CONCLUSION

This study shows the added prognostic value of more advanced CT modalities in acute ICH evaluation. NCCT, single-phase CTA, and multiphase CTA scores may help to refine the selection of patients at risk of expansion in different decision-making scenarios.

KEY POINTS

• This study shows the added prognostic value of more advanced CT modalities in acute intracerebral hemorrhage evaluation. • The evaluation of single-phase and multiphase CTA markers provides a steadily increase in discrimination for intracerebral hemorrhage expansion over non-contrast CT markers. • Non-contrast CT, single-phase CTA, and multiphase CTA scores may help clinicians and researchers to refine the selection of patients at risk of intracerebral hemorrhage expansion in different decision-making scenarios.

Granulocytes-Rich Thrombi in Cerebral Large Vessel Occlusion Are Associated with Increased Stiffness and Poorer Revascularization Outcomes

We aim to identify a profile of intracranial thrombus resistant to recanalization by mechanical thrombectomy (MT) in acute stroke treatment. The first extracted clot of each MT was analyzed by flow cytometry obtaining the composition of the main leukocyte populations: granulocytes, monocytes, and lymphocytes. Demographics, reperfusion treatment, and grade of recanalization were registered. MT failure (MTF) was defined as final thrombolysis in cerebral infarction score IIa or lower and/or need of permanent intracranial stenting as a rescue therapy. To explore the relationship between stiffness of intracranial clots and cellular composition, unconfined compression tests were performed in other cohorts of cases. Thrombi obtained in 225 patients were analyzed. MTF were observed in 30 cases (13%). MTF was associated with atherosclerosis etiology (33.3% vs. 15.9%; p = 0.021) and higher number of passes (3 vs. 2; p < 0.001). Clot analysis of MTF showed higher percentage of granulocytes [82.46 vs. 68.90% p < 0.001] and lower percentage of monocytes [9.18% vs.17.34%, p < 0.001] in comparison to successful MT cases. The proportion of clot granulocytes (aOR 1.07; 95% CI 1.01-1.14) remained an independent marker of MTF. Among thirty-eight clots mechanically tested, there was a positive correlation between granulocyte proportion and thrombi stiffness (Pearson's r = 0.35, p = 0.032), with a median clot stiffness of 30.2 (IQR, 18.9-42.7) kPa. Granulocytes-rich thrombi are harder to capture by mechanical thrombectomy due to increased stiffness, so a proportion of intracranial granulocytes might be useful to guide personalized endovascular procedures in acute stroke treatment.

Sex and gender differences in acute stroke care: metrics, access to treatment and outcome. A territorial analysis of the Stroke Code System of Catalonia

INTRODUCTION

Previous studies have reported differences in the management and outcome of women stroke patients in comparison with men. We aim to analyze sex and gender differences in the medical assistance, access to treatment and outcome of acute stroke patients in Catalonia.

PATIENTS AND METHODS

Data were obtained from a prospective population-based registry of stroke code activations in Catalonia (CICAT) from January/2016 to December/2019. The registry includes demographic data, stroke severity, stroke subtype, reperfusion therapy, and time workflow. Centralized clinical outcome at 90 days was assessed in patients receiving reperfusion therapy.

RESULTS

A total of 23,371 stroke code activations were registered (54% men, 46% women). No differences in prehospital time metrics were observed. Women more frequently had a final diagnosis of stroke mimic, were older and had a previous worse functional situation. Among ischemic stroke patients, women had higher stroke severity and more frequently presented proximal large vessel occlusion. Women received more frequently reperfusion therapy (48.2% vs 43.1%, p < 0.001). Women tended to present a worse outcome at 90 days, especially for the group receiving only IVT (good outcome 56.7% vs 63.8%; p < 0.001), but not for the group of patients treated with IVT + MT or MT alone, although sex was not independently associated with clinical outcome in logistic regression analysis (OR 1.07; 95% CI, 0.94-1.23; p = 0.27) nor in the analysis after matching using the propensity score (OR 1.09; 95% CI, 0.97-1.22).

DISCUSSION AND CONCLUSION

We found some differences by sex in that acute stroke was more frequent in older women and the stroke severity was higher. We found no differences in medical assistance times, access to reperfusion treatment and early complications. Worse clinical outcome at 90 days in women was conditioned by stroke severity and older age, but not by sex itself.

Prehospital care process and hospital outcomes in stroke-code cases: comparison of basic and advance life support ambulance attendance

OBJECTIVES

To study prehospital care process in relation to hospital outcomes in stroke-code cases first attended by 2 different levels of ambulance. To analyze factors associated with a satisfactory functional outcome at 3 months.

MATERIAL AND METHODS

Prospective multicenter observational cohort study. All stroke-code cases attended by prehospital emergency services from January 2016 to April 2022 were included. Prehospital and hospital variables were collected. The classificatory variable was type of ambulance attending (basic vs advanced life support). The main outcome variables were mortality and functional status after ischemic strokes in patients who underwent reperfusion treatment 90 days after the ischemic episode.

RESULTS

Out of 22 968 stroke-code activations, ischemic stroke was diagnosed in 12 467 patients (54.3%) whose functional status was good before the episode. Basic ambulances attended 93.1%; an advanced ambulance was ordered in 1.6% of the patients. Even though there were differences in patient and clinical characteristics recorded during the prehospital process, type of ambulance was not independently associated with mortality (adjusted odds ratio [aOR], 1.1; 95% CI, 0.77-1.59) or functional status at 3 months (aOR, 1.05; 95% CI, 0,72-1,47).

CONCLUSION

The percentage of patient complications in stroke-code cases attended by basic ambulance teams is low. Type of ambulance responding was not associated with either mortality or functional outcome at 3 months in this study.

Management of acute stroke. Specific nursing care and treatments in the stroke unit

OBJECTIVE

This study provides a series of updated, evidence-based recommendations for the management of acute stroke. We aim to lay a foundation for the development of individual centres' internal protocols, serving as a reference for nursing care.

METHODS

We review the available evidence on acute stroke care. The most recent national and international guidelines were consulted. Levels of evidence and degrees of recommendation are based on the Oxford Centre for Evidence-Based Medicine classification.

RESULTS

The study describes prehospital acute stroke care, the operation of the code stroke protocol, care provided by the stroke team upon the patient's arrival at hospital, reperfusion treatments and their limitations, admission to the stroke unit, nursing care in the stroke unit, and discharge from hospital.

CONCLUSIONS

These guidelines provide general, evidence-based recommendations to guide professionals who care for patients with acute stroke. However, limited data are available on some aspects, showing the need for continued research on acute stroke management.

Cryptogenic stroke as a working diagnosis: the need for an early and comprehensive diagnostic work-up

In the Nordic Atrial Fibrillation and Stroke (NOR-FIB) study, the causes of ischemic stroke were identified in 43% of cryptogenic stroke patients monitored with implantable cardiac monitor (ICM), but one-third of these patients had non-cardioembolic causes. These results suggest the need for an early and comprehensive diagnostic work-up before inserting an ICM.

Association of Time of Day With Outcomes Among Patients Triaged for a Suspected Severe Stroke in Nonurban Catalonia

BACKGROUND

We aim to assess whether time of day modified the treatment effect in the RACECAT trial (Direct Transfer to an Endovascular Center Compared to Transfer to the Closest Stroke Center in Acute Stroke Patients With Suspected Large Vessel Occlusion Trial), a cluster-randomized trial that did not demonstrate the benefit of direct transportation to a thrombectomy-capable center versus nearest local stroke center for patients with a suspected large vessel stroke triaged in nonurban Catalonia between March 2017 and June 2020.

METHODS

We performed a post hoc analysis of RACECAT to evaluate if the association between initial transport routing and functional outcome differed according to trial enrollment time: daytime (8:00 am-8:59 pm) and nighttime (9:00 pm-7:59 am). Primary outcome was disability at 90 days, as assessed by the shift analysis on the modified Rankin Scale score, in patients with ischemic stroke. Subgroup analyses according to stroke subtype were evaluated.

RESULTS

We included 949 patients with an ischemic stroke, of whom 258 patients(27%) were enrolled during nighttime. Among patients enrolled during nighttime, direct transport to a thrombectomy-capable center was associated with lower degrees of disability at 90 days (adjusted common odds ratio [acOR], 1.620 [95% CI, 1.020-2.551]); no significant difference between trial groups was present during daytime (acOR, 0.890 [95% CI, 0.680-1.163]; P _interaction=0.014). Influence of nighttime on the treatment effect was only evident in patients with large vessel occlusion(daytime, acOR 0.766 [95% CI, 0.548-1.072]; nighttime, acOR, 1.785 [95% CI, 1.024-3.112] ; P _interaction<0.01); no heterogeneity was observed for other stroke subtypes (P _interaction>0.1 for all comparisons). We observed longer delays in alteplase administration, interhospital transfers, and mechanical thrombectomy initiation during nighttime in patients allocated to local stroke centers.

CONCLUSIONS

Among patients evaluated during nighttime for a suspected acute severe stroke in non-urban areas of Catalonia, direct transport to a thrombectomy-capable center was associated with lower degrees of disability at 90 days. This association was only evident in patients with confirmed large vessel occlusion on vascular imaging. Time delays in alteplase administration and interhospital transfers might mediate the observed differences in clinical outcome.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02795962.

Intracranial atherosclerotic plaque enhancement and long-term risk of future strokes: A prospective, longitudinal study

BACKGROUND AND PURPOSE

The prognostic significance of postcontrast enhancement of intracranial atheromatous plaque is uncertain. Prospective, long-term follow-up studies in Caucasians, using a multicenter design, are lacking. We aimed to evaluate whether this radiological sign predicts long-term new stroke in symptomatic and asymptomatic intracranial atherosclerotic disease (ICAD) patients.

METHODS

This was a prospective, observational, longitudinal, multicenter study. We included a symptomatic and an asymptomatic cohort of ICAD patients that underwent 3T MRI including high-resolution sequences focused on the atheromatous plaque. We evaluated grade of stenosis, plaque characteristics, and gadolinium enhancement ratio (postcontrast plaque signal/postcontrast corpus callosum signal). The occurrence of new events was evaluated at 3, 6, 9, and 12 months and annually thereafter. The association between plaque characteristics and new stroke was studied using Cox multiple regression survival analysis and Kaplan-Meier curves.

RESULTS

Forty-eight symptomatic and 13 asymptomatic patients were included. During 56.3 ± 16.9 months, 11 patients (18%) suffered a new event (seven ischemic, two hemorrhagic, and two transient ischemic attacks). A receiver operating characteristic curve identified an enhancement ratio of >1.77 to predict a new event. In a multivariable Cox regression, postcontrast enhancement ratio >1.77 (hazard ratio [HR]= 3.632; 95% confidence interval [CI], 1.082-12.101) and cerebral microbleeds (HR = 5.244; 95% CI, 1.476-18.629) were independent predictors of future strokes. Patients with a plaque enhancement ratio >1.77 had a lower survival free of events (p < .05).

CONCLUSIONS

High intracranial postcontrast enhancement is a long-term predictor of new stroke in ICAD patients. Further studies are needed to elucidate whether postcontrast enhancement reflects inflammatory activity of intracranial atheromatous plaque.

Intracranial Artery Calcifications Profile as a Predictor of Recanalization Failure in Endovascular Stroke Treatment

BACKGROUND

Acute ischemic stroke with large or medium-vessel occlusion associated with intracranial artery calcification (IAC) is an infrequent phenomenon presumably associated with intracranial atherosclerotic disease. We aimed to characterize IAC and its impact on endovascular treatment outcomes.

METHODS

We performed a retrospective cross-sectional study of consecutive patients with stroke treated with thrombectomy from January 2020 to July 2021 in our institution. We described IAC findings (length, density, and location pattern) on baseline noncontrast computed tomography. Patients were divided into 3 groups: IAC related to the occlusion location (symptomatic-IAC group), unrelated to the occlusion (asymptomatic-IAC group), and absence of any IAC (non-IAC group). We analyzed the association between the IAC profile and outcomes using logistic regression models. Intracranial angioplasty and stenting were considered rescue treatments.

RESULTS

Of the 393 patients included, 26 (6.6%) patients presented a symptomatic-IAC, 77 (19.6%) patients an asymptomatic-IAC, and in 290 (73.8%) patients no IAC was observed. The rate of failed recanalization (expanded Thrombolysis in Cerebral Infarction 0-2a) before rescue treatment was higher in symptomatic-IAC (65.4%) than in asymptomatic-IAC (15.6%; P<0.001) or non-IAC (13.4%; P<0.001). Rescue procedures were more frequently performed in symptomatic-IAC (26.9%) than in asymptomatic-IAC (1.3%; P<0.001) and non-IAC (4.1%; P<0.001). After adjusting for identifiable clinical and radiological confounders, symptomatic-IAC emerged as an independent predictor of failed recanalization (odds ratio, 11.89 [95% CI, 3.94-35.91]; P<0.001), adoption of rescue procedures (odds ratio, 12.38 [95% CI, 2.22-69.09]; P=0.004), and poor functional outcome (90-day modified Rankin Scale score ≥3; odds ratio, 3.51 [95% CI, 1.02-12.00]; P=0.046).

CONCLUSIONS

The presence of IAC related to the occlusion location is associated with worse angiographic and functional outcomes. Therefore, identification of symptomatic-IAC on baseline imaging may guide optimal endovascular treatment strategy, predicting the need for intracranial stenting and angioplasty.

Abstract 95: High Proportion Of Granulocytes Form Intracranial Thrombus Is Associated With Increased Stiffness And Resistance To Endovascular Recanalization

Hypothesis: We aim to identify a profile of intracranial thrombus resistant to recanalization by standard mechanical thrombectomy (MT) in acute stroke treatment.

Methods: First extracted clot of each MT were analyzed by Flow Cytometry obtaining composition of main leukocyte populations: granulocytes, monocytes and lymphocytes. Demographics, reperfusion treatment and grade of recanalization were registered. MT Failure ( MTF) was defined as final Thrombolysis in Cerebral Infarction score IIa or lower and/ or need of permanent intracranial stenting as a rescue therapy after standard MT. In other cohort of cases, unconfined compression tests were performed to explore stiffness of retrieved clots . We looked for correlation between mechanical characterization tests and clot composition.

Results: Among 225 patients, there were 13 % of MTF that were significantly associated to atherosclerosis etiology ( 33.3% vs. 15.9% ; p 0.021) , more passes ( 3 vs. 2; p <0.001), higher proportion of clot granulocytes ( 82.46% vs. 68.90% ; p <0.001) and lower proportion of clot monocytes ( 9.18% vs.17.34% ; p<0.001). The proportion of clot granulocytes (aOR 1.07; 95% CI 1.01-1.14) remained as an independent marker of MTF. Among Thirty eight clots tested by unconfined compression median clot stiffness was 30.2 (IQR, 18.9-42.7) kPa. There was a positive correlation between granulocyte proportion and thrombi stiffness (Pearson’s r=0.35, p=0.032).

Conclusions: There is a positive correlation between granulocyte proportion and thrombi stiffness that may explain endovascular resistance to recanalization. Influence of granulocytes within thrombus may be a target for future reperfusion treatments.

Abstract TP2: Iv-thrombolysis Improves Perfusion Profiles In Patients With Anterior Circulation Occlusion Regardless Of Recanalization

Introduction: Recent publications suggest a positive added effect of iv-thrombolysis (IVT) in patients that undergo endovascular treatment (EVT). It is hypothesized that thrombolytics might have a beneficial impact on microcirculation beyond recanalization. We aim to analyze the potential impact of IVT in patients who underwent a repeated CTP after interhospital transfer.

Methods: We retrospectively screened 116 patients transferred to our comprehensive stroke center from a primary stroke center capable to perform CTP from June 2021 to August 2022. We collected clinical and radiological data of patients that underwent CTP at both centers, which were analyzed with Rapid software. A neurointerventionalist assessed the occlusion location in CTA.

Results: Twenty-eight patients with anterior circulation occlusion underwent two multimodal studies, median time between CTPs was 168[142-190]min. Fifteen (53.6%) patients received IVT in the primary stroke center and 13(46.4%) received EVT. Reperfusion occurred in 3(10.7%) cases, migration to distal segments in 5(17.9%). Among the 20 patients without changes in the occlusion location, CTP volumes remained stable (Tmax>6s 61[41-141]ml vs 62[24-178], p=0.72; Tmax>10s 19[8-96] vs 13[0-105], p=0.55; CBF30 0[0-66] vs 0[0-65], p=0.99). CTP volumes tended to decrease with IVT, but a modest increase was observed in patients that did not receive IVT (Tmax>6s -17[-29,+8]ml vs +22[-8,+42], p=0.08; Tmax>10s -8[-16,+6] vs +6[0,+37], p=0.10; CBF<30% 0[-6,0] vs 0[0,+4], p=0.14) (figure). In a linear regression to predict CTP volumes in the second center, interaction between baseline values and IVT was significant for Tmax>10s (p=0.06) and CBF<30% (p<0.05).

Conclusion: In acute stroke patients with a LVO, no substantial changes are expected in CTP volumes in the absence of recanalization. However, patients that receive IVT tend to present reduced hypoperfusion volumes as compared with patients that do not receive IVT.

Abstract 155: NORAHOME. A Virtual Multimodal Stroke Remote Monitoring Hospitalization Program

Background and Aims: The rising pressure on medical services, highlighted throughout the pandemic, has revealed a need for alternative methods of hospital care. Our objective is to evaluate a home hospitalization virtual multimodal monitoring program (NORAHOME) for patients who have had a previous transient ischemic attack (TIA) or minor stroke, as an efficient strategy compared to Routine Clinical Practice (RCP).

Methods: A prospective cohort study of consecutive patients with a suspected TIA or minor stroke evaluated at the emergency room of a tertiary hospital by a neurologist between 1st December 2020 and 1st June 2022, had completed NORAHOME and was compared with a historic control group of patients with a suspected TIA or minor stroke who had completed a conventional hospitalization (RCP) between 1st June and 30th November 2020.

Results: 430 patient cases were analyzed, 215 patients in the prospective group were compared with a retrospective cohort of the same number of patients. Mean age 75.21 ± 12.6 years; 54.9% women. In the NORAHOME group we observed a recurrence rate of 2.3% (5 patients) and mortality of 2.8% (6 patients) during the follow up. In the RCP group 6.5% (14 patients) presented recurrence and 7% (15 patients) died. No significant differences were found in the risk of early recurrence, emergency room readmission or functional outcome between the groups.

Conclusions: In our series of TIA and minor stroke patients, NORAHOME is a safe strategy compared to RCP. The development and implementation of digital home-hospitalization programs may reduce direct hospital costs by shortening length of stay and reducing hospital readmission. Moreover, the program improves self-assessed health outcomes reported by patients and their experience with the healthcare system compared to the RCP.

Abstract TP120: Noncontrast Ct, Single-phase Cta, And Multiphase Cta Intracerebral Hemorrhage Expansion Scores

Background: Several noncontrast computed tomography (NCCT), single-phase computed tomography angiography (CTA), and multiphase CTA markers of intracerebral hemorrhage (ICH) expansion have been previously proposed. We derived and validated three scores for the prediction of hematoma expansion depending on the use of NCCT, single-phase CTA, or multiphase CTA markers of hematoma expansion.

Methods: We prospective studied 276 consecutive patients with ICH within 6 hours from symptom onset. After deriving NCCT, single-phase CTA, and multiphase CTA scores in a 5-year period population (n=156), we validated them in a different 3-year period population (n=120). Outcome parameters included substantial hematoma expansion >6 mL or >33% at 24 hours (primary outcome) and poor outcome (mRS score >2) at 90 days.

Results: The most accurate marker of hematoma expansion was spot sign in phase 1 of multiphase CTA (80.3%). The four independent predictors of substantial hematoma expansion included in the different scores were ultraearly hematoma growth (uHG) >5 mL/h, heterogeneous density, spot sign in phase 1 of multiphase CTA, and spot sign in any phase of multiphase CTA (Table). On each of the three scores, the proportion of patients that experienced substantial hematoma expansion increased with each point increase. C-index for both substantial hematoma expansion and poor outcome in the derivation and validation cohort was lower in NCCT expansion score than in single-phase CTA expansion score which, in turn, was lower than in multiphase CTA expansion score (Table).

Conclusions: This study demonstrates the added prognostic value of more advanced CT modalities in acute ICH evaluation. Single-phase CTA score and, especially, multiphase CTA score, are more robust than NCCT score in the prediction of hematoma expansion and poor outcome. These scores may help to refine the selection of patients at risk of expansion and poorest outcomes in different decision-making scenarios.

Abstract WP4: Intravenous Thrombolysis And Outcomes In Patients With Large-vessel Stroke Directly Admitted Or Transferred To A Thrombectomy-capable Center

Objective: To assess whether the effect of intravenous thrombolysis in patients with large-vessel occlusion differed between patients directly admitted to thrombectomy-capable centers and patients transferred from local stroke centers without thrombectomy capabilities.

Methods: We included 3206 patients with an acute ischemic large-vessel stroke with first imaging within 7 hours after onset that were directly admitted to thrombectomy-capable centers and treated with thrombectomy, or transferred from local stroke centers for thrombectomy evaluation, between 2017 and 2021 in Catalonia, Spain. Primary outcome was the degree of disability at 90 days, as evaluated by the shift analysis on the mRs score. Secondary outcomes included mortality at 90 days and the rate of parenchymal hemorrhage and successful reperfusion. Inverse-probability weighting clustered at the type of stroke center was used to estimate the effects.

Results: The analysis included 2268 patients (975[49%] treated with thrombolysis) directly admitted to thrombectomy-capable centers and 938 patients (580[66%] treated with thrombolysis and 616[67%] treated with thrombectomy) transferred from local stroke centers (mean age 72±13 years, median NIHSS score 17[IQR 12-21], 1363 female[48%]). Patients treated with intravenous thrombolysis were younger, had shorter time from onset to first image acquisition, and higher rates of wake-up stroke, atrial fibrillation and anticoagulation intake. The effect of intravenous thrombolysis on the primary outcome was similar in patients directly admitted to thrombectomy-capable centers (acOR 1.50, 95% CI 1.24-1.81) and patients transferred from local stroke centers (acOR 1.44, 95% CI 1.04 to 2.01)(p interaction =0.68). Patients treated with intravenous thrombolysis had lower mortality rate, higher rate of parenchymal hematoma and similar rate of successful reperfusion, with no difference according to type of center (p interaction >0.1).

Conclusion: Administration of intravenous thrombolysis in patients with a large-vessel stroke with intention to thrombectomy was associated with higher odds of good functional outcome and higher rates of parenchymal hematoma, independently of the type of stroke center were it was administered.

Abstract WP21: Staged Implementation Of A Rapid, Intensive And Sustained Blood Pressure Protocol In Patients With Acute Intracerebral Hemorrhage

Background and Purpose: The potential benefit of blood pressure (BP) lowering in intracerebral hemorrhage (ICH) patients is time-dependent and is an easy and modifiable treatment applicable to different hospital scenarios. However, previous clinical trials did not establish consensus about the best BP strategy to achieve a rapid and sustained BP control. We aimed to assess the impact of learning a staged implementation of rapid-intensive-sustained BP protocol on time targets and BP control rate over the first 24 hours of ICH.

Methods: We conducted a retrospective analysis of data prospectively collected of consecutive patients with spontaneous ICH (<6h) and systolic BP (SBP) >150 mmHg under a rapid (antihypertensive IV bolus by a stroke nurse at CT scan), intensive (SBP target <140 mmHg within 1 hour after BP agent onset),and sustained (antihypertensive continuous infusion immediately after IV bolus) 24-hour BP protocol during a 6-year period. BP was recorded regularly according to the following schedule: every 15 minutes (0-6 hours); every 30 minutes (6h to 12h), and every 60 minutes (12h to 24h). We recorded the time from BP treatment onset to SBP target achievement and the rate of SBP sustention below target (<140 mm Hg) at all time frames. The protocol implementation was divided in 6 consecutive year periods.

Results: A total of 207 patients were included in the study. Compared between the periods, the frequency of SBP target achievement during the first hour was increased steadily over different periods(33.3% vs. 54.5% vs. 69.2% vs 69.4% vs 75% and 59.7%; P=0.024 ); median time to SBP target achievement tended to be lower during the evolution of protocol assessment (120 [45-240] min; 49.5 [30-101] min; 53 [29-82] min; 47 [28-74] min; 48 [27-66] min; 50 [30-85] min; P=0.054 ) and SBP sustention rate below the target improve during the acute phase at different time frames, including 2h (26.3% vs. 71.9% vs 60% vs 73.9% vs. 57,7% vs 59.5%; P= 0.012 ), 4h (57.1% vs. 63.3% vs 87.5% vs 85% vs. 61.5% vs. 69.2%; P= 0.05 ), 6h (60.9% vs. 58.6%, vs 95.5% vs 84.4% vs 58.3% vs. 75%; P=0.009 ).

Conclusions: Rapid-intensive-sustained BP protocol is a good intervention to both achieve a rapid BP target and reduce time delays,and improve the rates of BP control over the acute phase of ICH patients.

Intensive 90-day textile wearable Holter monitoring: an alternative to detect paroxysmal atrial fibrillation in selected patients with cryptogenic stroke

We aimed to demonstrate the feasibility of 90-day cardiac monitoring with an external Holter device and to find a target population able to benefit from such a technique. Cryptogenic stroke patients were continuously monitored for 90 days with a textile wearable Holter (TWH). Compliance and quality of the monitoring were assessed by the number of hours of ECG stored per month. Mean predictors of pAF, including age, gender, stroke severity, and atrial size (LAVI), were evaluated. One-year follow-up assessed pAF detection outside per protocol monitoring. Out of 224 patients included in 5 stroke centers, 163 patients (72.76%) fulfilled the criteria for the protocol. Median monitoring time was similar among the three months. Per protocol pAF detection reached 35.37% at 90 days. The age (OR 1.095; 95% CI 1.03-1.14) and the LAVI (OR 1.055; 95% CI 1.01-1.09) independently predicted pAF. The cut-off point of 70 years (AUC 0.68) (95% CI 0.60-0.76) predicted pAF with a sensitivity of 75.8% and specificity of 50.5%. The LAVI cut-off point of 28.5 (AUC 0.67) (95% CI 0.56-0.77) had a sensitivity of 63.6% and a specificity of 61.8% to detect pAF. The combination of both markers enhanced the validity of pAF detection sensitivity to 89.6%, with a specificity of 27.59%. These patients had increased risk of pAF during the 90-day monitoring HR 3.23 (χ² 7.15) and beyond 90 days (χ² 5.37). Intensive 90-days TWH monitoring detected a high percentage of pAF. However, a significant number of patients did not complete the monitoring. Patients older than 70 years and with enlarged left atria benefitted more from the protocol.

Redefining Disability: Patient-Reported Outcome Measures After Minor Stroke and Transient Ischemic Attack

BACKGROUND

Long-term outcome assessment patients with stroke is not fully captured by usual clinical scales such as the modified Rankin Scale (mRS). Patient-reported outcome measures (PROMs) are standardized and validated assessments that consider clinical outcomes from the patient perspective. We aim to analyze the added value of PROMs in patients with transient ischemic attack and minor stroke.

METHODS

We included consecutive patients with minor stroke or transient ischemic attack (National Institutes of Health Stroke Scale score 0-5) from April 2020 to October 2021 that participated in the PROMs-through-App program (NORA, NoraHealth Barcelona Spain). Clinician and self-evaluated outcomes were assessed at 90 days: clinician-evaluated mRS, self-reported mRS, the 10-item patient-reported outcome measures questionnaire global health survey (v1.2), Hospital Anxiety and Depression Scale, and the Fatigue Assessment Scale. We evaluated the acceptability (response rate), reliability (internal consistency), and construct validity (correlation with mRS and between scales) of each questionnaire.

RESULTS

We included 355 patients in the analysis, response rate was patient-reported outcome measures questionnaire 71.3% (253), Hospital Anxiety and Depression Scale 70.7% (251), Fatigue Assessment Scale 71.8% (255), and self-assessed mRS 66.8% (237). PROMS internal consistency was good or excellent, while agreement between clinician and self-reported mRS was fair (k=0.34). Rate of abnormal PROMS scores were as follows (all responders versus clinician-reported mRS score 0-2): patient-reported outcome measures questionnaire mental health (43.1% versus 36.3%), physical health (48.6% versus 43.6%); Hospital Anxiety and Depression Scale-anxiety (21.9% versus 17.7%) and depression (17.1% versus 13.3%); and Fatigue Assessment Scale (40.8% versus 36.4%). PROMs scores correlated with clinician and self-reported mRS at 90 days.

CONCLUSIONS

Evaluation of PROMs using a mobile-app-based communication system is a reliable and valid strategy to assess the outcome of patients from their perspective after a mild stroke or transient ischemic attack.

Systematic CT perfusion acquisition in acute stroke increases vascular occlusion detection and thrombectomy rates

BACKGROUND

In patients with stroke, current guidelines recommend non-invasive vascular imaging to identify intracranial vessel occlusions (VO) that may benefit from endovascular treatment (EVT). However, VO can be missed in CT angiography (CTA) readings. We aim to evaluate the impact of consistently including CT perfusion (CTP) in admission stroke imaging protocols.

METHODS

From April to October 2020 all patients admitted with a suspected acute ischemic stroke underwent urgent non-contrast CT, CTA and CTP and were treated accordingly. Hypoperfusion areas defined by time-to-maximum of the tissue residue function (Tmax) >6 s, congruent with the clinical symptoms and a vascular territory, were considered VO (CTP-VO). In addition, two experienced neuroradiologists blinded to CTP but not to clinical symptoms retrospectively evaluated non-contrast CT and CTA to identify intracranial VO (CTA-VO).

RESULTS

Of the 338 patients included in the analysis, 157 (46.5%) presented with CTP-VO (median Tmax >6s: 73 (29-127) mL). CTA-VO was identified in 83 (24.5%) of the cases. Overall CTA-VO sensitivity for the detection of CTP-VO was 50.3% and specificity was 97.8%. Higher hypoperfusion volume was associated with increased CTA-VO detection (OR 1.03; 95% CI 1.02 to 1.04). EVT was performed in 103 patients (30.5%; Tmax >6s: 102 (63-160) mL), representing 65.6% of all CTP-VO. Overall CTA-VO sensitivity for the detection of EVT-VO was 69.9% and specificity was 95.3%. Among patients who received EVT, the rate of false negative CTA-VO was 30.1% (Tmax >6s: 69 (46-99.5) mL).

CONCLUSION

Systematically including CTP in acute stroke admission imaging protocols may increase the diagnosis of VO and rate of EVT.

Added value of patient-reported outcome measures (PROMs) after an acute stroke and early predictors of 90 days PROMs

Introduction

Value-based health care represents a patient-centered approach by valuing Patient-Reported Outcome Measures (PROMs). Our aim was to describe the additional value of PROMs after an acute stroke over conventional outcome measures and to identify early predictors of poor PROMs.

Methods

Acute stroke patients discharged from a tertiary care hospital followed by a web/phone-based PROMs collection program in the post hospitalization phase. Main PROMs involve anxiety and depression (HADS) (each defined by HADS ≥ 10) and global physical (PHY-) and mental (M-) health (PROMIS-10). PROMIS cut-off raw values of normality were: PHY-PROMIS ≥ 13 and M-PROMIS ≥ 11. An overall health status (OHS) from 0 to 100 was also determined. PROMs related to the different modified Rankin Scale (mRS) grades were defined. Early predictors of PROMs were evaluated.

Results

We included 1321 stroke patients, mean age 75 (± 8.6) and 55.7% male; 77.7% returned home. Despite a favorable mRS at 3 months (< 3), a relevant rate of patients considered without symptoms or with mild disability showed unfavorable results in the measured PROMs (8% unfavorable OHS, 15% HAD-depression, 12.1% HAD-anxiety, 28.7% unfavorable M-PROMIS and 33.1% unfavorable PHY-PROMIS results). Along follow-up, only PHY-PROMIS and OHS showed significant improvement (p < 0.01 and 0.03, respectively). The multivariate analysis including discharge variables showed that female sex, higher discharge mRS and discharge to socio-rehabilitation-center (SRC) were independent predictors of unfavorable results in PROMs (p < 0.01). When adding 7 days PROMs results, they emerged as the strongest predictors of 3 months PROMs.

Conclusions

A high proportion of stroke patients show unfavorable results in PROMs at 3 months, even those with favorable mRS, and most results obtained by PROMs during follow-up continued to indicate alterations. Female sex, mRS and discharge to SRC predicted unfavorable results in PROMs, but the strongest predictors of 3 months PROMs were the results of the 7 days PROMs.

Multiparametric Neuroimaging and Its Association with Non-Contrast Computed Tomography in Late-Window Large Vessel Occlusion Acute Stroke

INTRODUCTION

Endovascular treatment (EVT) for acute ischemic stroke (AIS) between 6 and 24 h is established as a standard of care among patients selected by multiparametric neuroimaging. We aimed to explore neuroimaging parameters in late-window large vessel occlusion (LVO) patients and its association with non-contrast computed tomography (NCCT) findings.

METHODS

We included consecutive AIS patients within 6-24 h from the symptoms onset with LVO. We described multiparametric imaging findings, the rate of patients who fulfilled imaging perfusion criteria according to the DAWN and DEFUSE-3 trials that define the computed tomography perfusion mismatch (CTP-MM) group and its association with NCCT focused on Alberta Stroke Program Early CT Score (ASPECTS). We also analyzed the association between neuroimaging parameters and the clinical outcome determined by the 90-day modified Rankin scale (mRS).

RESULTS

We included 206 patients, of them, 176 (85.4%) presented CTP-MM and 184 (89.3%) presented an ASPECTS ≥6 on admission. The rate of CTP-MM was 90.8% in patients with ASPECTS ≥6, compared with 40.9% in those with low ASPECTS. ASPECTS was moderately correlated with ischemic core determined by cerebral blood flow <30% volume (rS = -0.557, p < 0.001). In EVT-treated patients (185, 89.8%), after adjusting for identifiable confounders, the presence of CTP-MM was a predictor of 90-day functional independence (OR: 3.38; 95% CI: 1.01-11.29; p = 0.048). We did not find an association between CTP-MM and 90-day functional disability (ordinal mRS shift, aOR: 1.39; 95% CI: 0.58-3.34; p = 0.459).

CONCLUSIONS

A great majority of patients who presented a LVO in the late window fulfilled guidelines imaging criteria to undergo EVT, especially those with high ASPECTS (≥6). Our data suggest that NCCT with CT angiography could be a reasonable approach for AIS treatment selection also in the late window.

Workflows and Outcomes in Patients With Suspected Large Vessel Occlusion Stroke Triaged in Urban and Nonurban Areas

BACKGROUND

We aim to compare the outcome of patients from urban areas, where the referral center is able to perform thrombectomy, with patients from nonurban areas enrolled in the RACECAT trial (Direct Transfer to an Endovascular Center Compared to Transfer to the Closest Stroke Center in Acute Stroke Patients With Suspected Large Vessel Occlusion).

METHODS

Patients with suspected large vessel occlusion stroke, as evaluated by a Rapid Arterial Occlusion Evaluation score of ≥5, from urban catchment areas of thrombectomy-capable centers during RACECAT trial enrollment period were included in the Stroke Code Registry of Catalonia. Primary outcome was disability at 90 days, as assessed by the shift analysis on the modified Rankin Scale score, in patients with an ischemic stroke. Secondary outcomes included mortality at 90 days, rate of thrombolysis and thrombectomy, time from onset to thrombolysis, and thrombectomy initiation. Propensity score matching was used to assemble a cohort of patients with similar characteristics.

RESULTS

The analysis included 1369 patients from nonurban areas and 2502 patients from urban areas. We matched 920 patients with an ischemic stroke from urban areas and nonurban areas based on their propensity scores. Patients with ischemic stroke from nonurban areas had higher degrees of disability at 90 days (median [interquartle range] modified Rankin Scale score, 3 [2-5] versus 3 [1-5], common odds ratio, 1.25 [95% CI, 1.06-1.48]); the observed average effect was only significant in patients with large vessel stroke (common odds ratio, 1.36 [95% CI, 1.08-1.65]). Mortality rate was similar between groups(odds ratio, 1.02 [95% CI, 0.81-1.28]). Patients from nonurban areas had higher odds of receiving thrombolysis (odds ratio, 1.36 [95% CI, 1.16-1.67]), lower odds of receiving thrombectomy(odds ratio, 0.61 [95% CI, 0.51-0.75]), and longer time from stroke onset to thrombolysis (mean difference 38 minutes [95% CI, 25-52]) and thrombectomy(mean difference 66 minutes [95% CI, 37-95]).

CONCLUSIONS

In Catalonia, Spain, patients with large vessel occlusion stroke triaged in nonurban areas had worse neurological outcomes than patients from urban areas, where the referral center was able to perform thrombectomy. Interventions aimed at improving organizational practices and the development of thrombectomy capabilities in centers located in remote areas should be pursued.

REGISTRATION

URL: https://www.

CLINICALTRIALS

gov; Unique identifier: NCT02795962.

European Stroke Organisation (ESO) guideline on screening for subclinical atrial fibrillation after stroke or transient ischaemic attack of undetermined origin

We aimed to provide practical recommendations for the screening of subclinical atrial fibrillation (AF) in patients with ischaemic stroke or transient ischaemic attack (TIA) of undetermined origin. These guidelines are based on the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology. Five relevant Population, Intervention, Comparator, Outcome questions were defined by a multidisciplinary module working group (MWG).

Longer duration of cardiac rhythm monitoring increases the detection of subclinical AF, but the optimal monitoring length is yet to be defined. We advise longer monitoring to increase the rate of anticoagulation, but whether longer monitoring improves clinical outcomes needs to be addressed. AF detection does not differ from in- or out-patient ECG-monitoring with similar monitoring duration, so we consider it reasonable to initiate in-hospital monitoring as soon as possible and continue with outpatient monitoring for more than 48h. Although insertable loop recorders (ILR) increase AF detection based on their longer monitoring duration, comparison with non-implantable ECG devices for similar monitoring time is lacking. We suggest the use of implantable devices, if feasible, for AF detection instead of non- implantable devices to increase the detection of subclinical AF. There is weak evidence of a useful role for blood, ECG, and brain imaging biomarkers for the identification of patients at high risk of AF. In patients with patent foramen ovale, we found insufficient evidence from RCT, but prolonged cardiac monitoring in patients >55 years is advisable for subclinical AF detection. To conclude, in adult patients with ischaemic stroke or TIA of undetermined origin, we recommend longer duration of cardiac rhythm monitoring of more than 48h and if feasible with IRL to increase the detection of subclinical AF.

Patient-reported outcome measures after thrombectomy in patients with acute stroke: fine-tuning the modified Rankin Scale

BACKGROUND

In patients with stroke undergoing endovascular treatment (EVT), long-term outcome is usually only evaluated by the modified Rankin Scale (mRS). Patient-reported outcomes (PROMs) are standardized assessments that consider clinical outcomes from the perspective of the patient. We aimed to evaluate PROMs through a smartphone-based communication platform in patients with stroke who received EVT.

METHODS

Consecutive patients with stroke who underwent EVT were offered to participate in the PROMs-through-App program (NORA). A set of standardized PROMs were collected at 7, 30 and 90 days after discharge. Disability was determined by clinicians (mRS) at 90 days. To characterize the potential ceiling effect of mRS in the assessment of different domains, the rate of abnormal PROMs among patients with excellent outcome (mRS 0-1) was calculated.

RESULTS

From June 2020 to October 2021, 186 patients were included. The median PROMs collection rate per patient was 80% (50-100%). A correlation was consistently seen between disability measured by mRS and the different PROMs. The rate of abnormal PROMs ranged from 20.83% (HADS at 7 days) to 59.61% (Mental PROMIS at 7 days). At 90 days, among patients with an excellent outcome, the rate of abnormal PROMs ranged from 8.7% (HADS) to 47.83% (Physical PROMIS).

CONCLUSIONS

A specifically designed digital platform allows a high collection rate of PROMs among stroke patients who underwent EVT. The mRS score shows a ceiling effect and seems insufficient to fine-tune long-term clinical results. The use of PROMs may allow a better characterization of long-term outcome profiles after EVT.

Abstract 26: Timing The Optimal Transfer Modality For Suspected Large-vessel Stroke Patients: A Post-hoc Analysis Of The Racecat Trial

Introduction: Current recommendations for regional stroke destination suggest that patients with an acute severe stroke should be triaged based on estimated time to arrival to a thrombectomy-capable center. We aimed to evaluate which time period available at the time that patient is triaged is able to discriminate which transfer modality should be chosen.

Methods: We built and ordered logistic regression model adjusted for multiple comparisons with the RACECAT trial population using time periods available during triage: time from onset to emergency medical services (EMS) evaluation, estimated time of arrival to the thrombectomy-capable center and between centers distance. Estimated times were computed using a distance matrix API. Primary outcome was disability at 90 days, as assessed by the shift analysis on the modified Rankin score.

Results: Of the 1369 patients evaluated, median time from onset to EMS evaluation, estimated time to arrival to the thrombectomy-capable center and between centers distances were 65 minutes (interquartile ratio (IQR) 43 to 138), 61 minutes (IQR 36 to 80) and 62 minutes (IQR 36 to 73), respectively. In patients transferred to local stroke centers, delay in EMS evaluation was associated with higher degrees of disability (for each 30 minutes delay, adjusted common odds ratio (acOR) 1.035, 97.5% confidence interval (CI) 1.005 to 1.066), with no influence in patients directly transferred to thrombectomy-capable centers (for each 30 minutes delay, acOR 0.999, 97.5% CI 0.981 to 1.018) (p interaction =0.048). In patients evaluated by EMS above 120 minutes after stroke onset, direct transfer to a thrombectomy-capable center was associated with lower degrees of disability (acOR 1.494, 95% CI 1.026 to 2.174).

Conclusion: In the RACECAT trial, delay in EMS evaluation was associated with higher degrees of disability in patients transferred to local stroke centers and may serve as a potential biomarker for prehospital triage optimization.

Abstract TP255: Lymphocytes And Platelets In Extracted Thrombus May Indicate The Etiology Of The Thrombus. Results From The Itacat Multicentric Registry

Aim: We performed a histological and immune analysis of the clot in acute stroke patients to detect surrogates of stroke etiology.

Methods: We conducted a prospective observational study of consecutive patients with acute stroke who underwent thrombectomy that obtained extracted thrombus (ITACAT study). Several staining were performed to evaluate red blood cells/fibrin (hematoxylin/eosin), platelets (CD61) and leucocytes (CD4, CD8 and CD20). All patients received CT angio to detect extra/intracranial vascular stenosis and 30-day cardiac monitoring to diagnose AF. According to TOAST classification the thrombi were classified in cardioembolic etiology CE (T-CE), due to symptomatic atherosclerosis (T-AT) and without any cause (T-CRYP). We excluded strokes due to double cause or incomplete workup.

Results: Of the 117 patients: 30 were T-AT, 55 were T-CE and 32 were T-CRYP. T-AT patients were younger: T-AT 68 years (60-77) Vs. T-CE 75 years (68-80) Vs. T-CRYP 72 years (55-81) (p=0.034). T-AT group had higher percentage of CD4: T-AT 6.52% (4-13) Vs. T-CE (3.31% (12.9) Vs .T-CRYP 3.72% (1.5-12) (p=0.015) and lower percentage of CD61: T-AT 51.18% (34-68) Vs. CE 64.70% (19.56) Vs. CRYP 70.3% (19) (p=0.001). There were no correlation between CD4 and platelets. Both CD4 OR 1.05 (1-1.10) (p=0.020) and CD61 (OR 0.96 (0.94-0.98) (p=0.01) independently predicted T-AT from the age. Final analysis (n=400 cases) will be ended in September 2021.

Conclusions: Patients with high percentage of CD4 and low percentage of CD61 are related to atherosclerosis etiology.

Abstract TP178: AI Based Personalized Stroke Predictor For Patient Awareness And Treatment Compliance

Personal prediction of stroke recurrence based on modifiable factors may enhance patient compliance to treatments and healthy lifestyles while optimizing resources of health centers. Vascular risk factors, socio-economic indicators and habits correlate with stroke morbidity and further recurrence. We aimed to estimate stroke recurrence probability as a function of time (3 months, &lt; 1 year and &gt; 1year), both at individual level and with larger classes of individuals. Clinical and socioeconomic public healthcare-based dataset of 41325 patients admitted with stroke diagnosis in 88 public hospitals over 6 years were analyzed.

Overall, 8509 patients presented a stroke (one or more) recurrence (20.6%), with the following temporal distribution: 3 months, 1 year and &gt; 1 year, 57%, 17% and 26% respectively. We developed a supervised-machine learning based study and identified modifiable and non-modifiable risk factors with stronger impact on risk of stroke recurrence. An algorithm able to provide individualized risk of stroke recurrence at 3 and 12 months was developed (AUROC = 0.80, for balanced classes). The risk can be continuously updated according to the status of modifiable risk factors.

We also calculated the survival curve for each patient, to detect different risk recurrence periods along time.

a) ROC curve for the three classes predicted.

b) Feature importance to explain the model for features modifiable by the patient or not c) Probability over time of “No stroke recurrence” in an example patient according to optimal (orange) or poor (blue) control of vascular risk factors

Machine learning analyses can improve risk prediction and offer individualized information to patients that can be used as feedback for secondary prevention strategies. Our approach is compatible with prevention strategies which, by continuous patient communication and feedbacks, make patients more likely to comply with treatment prescribed or lifestyle changes suggested.

Abstract WMP63: Artificial Intelligence Assessment Of Non-contrast Ct Increases Intracranial Occlusion Detection As Compared With Ct-angiograhy Readings

Artificial Intelligence (AI) can assist in vessel occlusion (VO) identification in acute stroke patients. We aim to investigate the impact of using an AI-based software for automated VO detection on non-contrast CT (AI-VO) as compared to CT-Aangiograpphy (CTA).

Methods: From April to October 2020 all patients admitted with a suspected acute ischemic stroke underwent urgent non-contrast CT / CTA / CTP and were treated accordingly. Hypoperfusion areas defined as Tmax>6s on CTP (RAPID software), congruent with the clinical symptoms and a vascular territory, were considered VO (CTP-VO: ground truth). In addition, two experienced neuroradiologists blinded to CTP but not to clinical symptoms retrospectively evaluated CT and CTA to identify intracranial VO (CTA-VO). AI-VO was automatically determined by an AI-based software (Methinks).

Results: Of the 338 patients included, 157 (46.5%) showed a CTP-VO (median Tmax>6s: 73[29-127]ml). Overall sensitivity to detect CTP-VO was 50.3% for CTA-VO and 66.9% for AI-VO; specificity was 97.8% for CTA-VO and 86.2% for AI-VO. EVT was performed in 103 patients (EVT-VO: 65.6% of CTP-VO; Tmax>6s: 102[63-160]ml); sensitivity to detect EVT-VO was 69% for CTA-VO and 79.6% for AI-VO; specificity was 95.3% for CTA-VO and 79.6% for AI-VO. The probability to detect a CTP-VO was higher with AI than with CTA for distal occlusions (figure). Accordingly, AI-VO sensitivity was higher than CTA-VO for angiographically confirmed M2/M3-MCA occlusions (80.7% vs 34.6%; p=0.002) but not for M1-MCA/ICA occlusions (82.1% Vs 88.1%;p=0.467).

Conclusion: AI-assisted vessel occlusion identification on non-contrast CT may be a useful tool in acute stroke evaluation, especially for distal VO identification, potentially increasing endovascular treatment in these cases.

Abstract WMP66: Multiparametric Neuroimaging And Its Association With Non-Contrast Computed Tomography In Late Window Large Vessel Occlusion Acute Stroke

Background: Endovascular treatment (EVT) for acute ischemic stroke (AIS) between 6 to 24 hours is established as a standard of care among patients selected by multiparametric neuroimaging. Therefore, we aimed to explore neuroimaging parameters in late window AIS large vessel occlusion (LVO) patients and the association between findings in non-contrast computed tomography (NCCT) and multiparametric CT.

Methods: We included consecutive AIS patients within 6-24 hours from symptoms onset with CTA-LVO. We studied potential associations between computed tomography mismatch defined by DAWN and/or DEFUSE-3 neuroimaging criteria (CTP-MM), infarct volume on CTP, and ASPECTS on NCCT. We also analyzed the association between neuroimaging parameters and outcome determined by 90-day mRS.

Results: We included 206 patients, of which 176 (85.4%) presented CTP-MM and 184 (89.3%) presented with an ASPECTS ≥ 6 on admission. The rate of CTP-MM was 90.8% in patients with ASPECTS ≥ 6, as compared with 40.9% in those with low ASPECTS [Figure 1A] . The ASPECTS correlated with infarct core, determined by Cerebral Blood Flow <30% volume (rP=-0.575, P<0.001). In EVT-treated patients (185, 89.8%), after adjusting for identifiable confounders, the presence of CTP-MM was a predictor of 90-day functional independence (OR 3.38; 95%CI 1.01-11.29; P=0.048). We did not find an association between CTP-MM and 90-day functional disability (ordinal mRS shift, aOR 1.39; 95% CI 0.58-3.34; P=0.459) [Figure 1B] .

Conclusions: A great majority of patients who presented a LVO in late window fulfilled guidelines imaging criteria to undergo EVT, especially those with high ASPECTS (≥ 6). Our data suggest that NCCT with CT angiography is a reasonable approach for acute ischemic stroke treatment selection also in the late window.

Abstract 94: Prospective Clinical Evaluation Of The Modified CDC Criteria For Diagnosis And Management Of Stroke Associated Pneumonia

Objective: Stroke-associated infections (SAI) and specially pneumonia (SAP) frequently complicate stroke, leading to poor outcome. The modified Center of Disease Control and Prevention (mCDC) diagnostic criteria for SAP have been proposed, but not yet validated. We aimed to analyze the fulfillment of these criteria for SAP diagnosis and antibiotic guidance, as well as compare clinical outcomes between mCDC-defined SAP and physician’s diagnosed pneumonia.

Methods: The PROTEUS study was a prospective, multicenter, observational study including ischemic stroke patients with baseline stroke severity (National Institutes of Health Stroke Scale) NIHSS≥4. Patients with concurrent infection or antibiotic use were excluded. During the first week after stroke, the mCDC criteria for SAP were daily assessed by the study investigators. Clinical diagnosis of pneumonia and other infections, and antibiotic use were recorded by treating physicians. Clinical outcome was assessed with the modified Rankin scale (mRS) at three months, and categorized into poor (mRS>2) and favorable (mRS≤2) outcome. The effect of criteria-defined SAP and physician-diagnosed SAP on clinical outcome was evaluated by logistic regression analysis.

Results: From July-2018 to May-2021, 340 patients were included in 9 stroke units from Spain. Of them, any SAI was diagnosed in 75 patients (22.1%), being 41 (12.1%) diagnosed as pneumonia by physicians. SAP according to mCDC criteria was diagnosed in 26 cases (7.6% of the cohort, 63.4% of physician’s diagnoses). Antibiotics were used in 88.5% of criteria-defined SAP and 73.3% in physician-diagnosed pneumonia (50% in patients with pneumonia not fulfilling mCDC criteria). In logistic regression analysis, criteria-defined SAP was an independent predictor of 3-month poor outcome (OR=7.13 (1.58-32.12)). However, physician-diagnosed pneumonia not fulfilling mCDC criteria was not an independent predictor of poor clinical outcome (OR=1.40 (0.38-5.08)).

Conclusions: Despite being associated with clinical outcome, mCDC criteria are not used in clinical practice, neither for SAP diagnosis nor to guide antibiotic therapy. Adherence to these criteria might reduce variability in clinical diagnosis and antibiotic overuse in stroke units.

Abstract 138: Thrombus Composition Is Associated With First Pass Recanalization

Introduction: Our objective is to identify thrombus composition associated with first pass recanalization (FPR) in mechanical thrombectomy (MT).

Methods: Intracranial thrombi obtained in MT were divided in two equal parts. One part was analyzed with anatomopathological studies to quantify fibrin, red-blood cell( Hematoxilin & Eosin) and platelets( cd61 Immunohistochemical staining ) , the other part was analyzed by flow cytometry to quantify leukocyte populations (granulocytes, lymphocytes and monocytes) and their relative proportions . FPR were defined as ≥ mTICI 2b after first pass in MT. Thrombi composition, baseline variables (demographics, previos use of antiplatelets or anticoagulants, blood pressure and blood glucose at hospital arrival ) etiology, intravenous fibrinolysis, ASPECTS score and first attempt thrombectomy devices: direct aspiration, stent retriever or combinations were compared between FPR and Non-FPR groups.

Results: Fifty percent (38/76) of the cases analyzed obtained FPR. There were no differences in baseline variables , etiology, Aspects score, previous use of fibrinolysis or type of device used for MT. The thrombi obtained with FPR presented higher proportion of red blood cells (33.64% vs 18.16% p = 0.048) and lymphocytes (10.07% vs 4.43% p = 0.042) and lower proportion of platelets (61, 48% vs 67.26% p = 0.042) in comparison to non-FPR group. The proportion of platelets was an independent marker of FPR (OR 0.97; CI 0.95-0.99). There was an inverse correlation between the proportion of platelets and lymphocytes (rho -0.44, p <0.001).

Conclusion: Platelets proportion in intracranial thrombus is an independent marker of first pass recanalization. Inverse relationship between lymphocytes and platelets may be a target for future reperfusion treatments

The Role of Vascular Imaging atReferral Centers in the Drip and Ship Paradigm

BACKGROUND

In drip-and-ship protocols, non-invasive vascular imaging (NIVI) at Referral Centers (RC), although recommended, is not consistently performed and its value is uncertain. We evaluated the role of NIVI at RC, comparing patients with (VI+) and without (VI-) vascular imaging in several outcomes.

METHODS

Observational, multicenter study from a prospective government-mandated population-based registry of code stroke patients. We selected acute ischemic stroke patients, initially assessed at RC from January-2016 to June-2020. We compared and analyzed the rates of patients transferred to a Comprehensive Stroke Center (CSC) for Endovascular Treatment (EVT), rates of EVT and workflow times between VI+ and VI- patients.

RESULTS

From 5128 ischemic code stroke patients admitted at RC; 3067 (59.8%) were VI+, 1822 (35.5%) were secondarily transferred to a CSC and 600 (11.7%) received EVT. Among all patients with severe stroke (NIHSS ≥16) at RC, a multivariate analysis showed that lower age, thrombolytic treatment, and VI+ (OR:1.479, CI95%: 1.117-1.960, p=0.006) were independent factors associated to EVT. The rate of secondary transfer to a CSC was lower in VI+ group (24.6% vs. 51.6%, p<0.001). Among transferred patients, EVT was more frequent in VI+ than VI- (48.6% vs. 21.7%, p<0.001). Interval times as door-in door-out (median-minutes 83.5 vs. 82, p= 0.13) and RC-Door to puncture (median-minutes 189 vs. 178, p= 0.47) did not show differences between both groups.

CONCLUSION

In the present study, NIVI at RC improves selection for EVT, and is associated with receiving EVT in severe stroke patients. Time-metrics related to drip-and-ship model were not affected by NIVI.

Time-resolved assessment of cortical venous drainage on multiphase CT angiography in patients with acute ischemic stroke

PURPOSE

Cortical vein opacification is not routinely assessed in patients presenting with acute ischemic stroke (AIS), and the value of temporal assessment of venous outflow is not known. We evaluated the utility of assessing cortical venous drainage over time using multiphase CT angiography (mCTA).

METHODS

Cortical venous drainage was assessed in patients from the Precise and Rapid Assessment of Collaterals Using Multi-Phase CTA in the Triage of Patients With Acute Ischemic Stroke for IA Therapy prospective multicenter cohort study of patients with symptoms of AIS with ICA and/or middle cerebral artery occlusion on baseline mCTA. Opacification of vein of Labbe, sphenoparietal sinus, superficial middle cerebral vein, and vein of Trolard of the affected hemisphere was graded as no (0), partial (1), or full (2) opacification in each mCTA phase. The venous opacification scores for each phase were added to generate a total venous score (TVS) (range 0-24). Primary outcome was 90-day modified Rankin score. Repeated measures analysis was used to assess the effect of phase timing on venous score on outcome.

RESULTS

Of 432 patients, 284 (65.7%) had proximal arterial occlusions. Median venous opacification score per phase (range 0-8) was 3 (IQR 1-6) in the first phase and increased in the second and third phases [median (IQR): 6 (5-8) and 8 (6-8), respectively] of the mCTA. In a multivariable analysis adjusting for age, baseline National Institutes of Health Stroke Scale, and Alberta stroke program early CT score, a significant association between TVS and 90-day mRS was noted ([adjusted cOR for TVS 6-11: 0.16 (95% CI 0.05-0.51); TVS 12-17: 0.18 (95% CI 0.06-0.57); TVS 18-24: 0.20 (0.06-0.63)]. Repeated measures analysis of venous scores from all three phases showed a significant effect of time/phase on TVS (p < 0.001).

CONCLUSION

This study concludes that venous opacification over time on multiphase CTA is associated with 90-day clinical outcome. There was however no added benefit of venous scoring vis-a-vis arterial collateral assessment in predicting outcome.

Impact of Multiphase Computed Tomography Angiography for Endovascular Treatment Decision-Making on Outcomes in Patients with Acute Ischemic Stroke

BACKGROUND AND PURPOSE

Various imaging paradigms are used for endovascular treatment (EVT) decision-making and outcome estimation in acute ischemic stroke (AIS). We aim to compare how these imaging paradigms perform for EVT patient selection and outcome estimation.

METHODS

Prospective multi-center cohort study of patients with AIS symptoms with multi-phase computed tomography angiography (mCTA) and computed tomography perfusion (CTP) baseline imaging. mCTA-based EVT-eligibility was defined as presence of large vessel occlusion (LVO) and moderate-to-good collaterals on mCTA. CTP-based eligibility was defined as presence of LVO, ischemic core (defined on relative cerebral blood flow, absolute cerebral blood flow, and cerebral blood volume maps) <70 mL, mismatch-ratio >1.8, absolute mismatch >15 mL. EVT-eligibility and adjusted rates of good outcome (modified Rankin Scale 0-2) based on these imaging paradigms were compared.

RESULTS

Of 289/464 patients with LVO, 263 (91%) were EVT-eligible by mCTA-criteria versus 63 (22%), 19 (7%) and 103 (36%) by rCBF, aCBF, and CBV-CTP-criteria. CTP and mCTA-criteria were discordant in 40% to 53%. Estimated outcomes were best in patients who met both mCTA and CTP eligibility-criteria and were treated with EVT (62% to 87% good outcome). Patients eligible for EVT by mCTA-criteria and not by CTP-criteria receiving EVT achieved good outcome rates of 53% to 57%. Few patients met CTP-criteria and not mCTA-criteria for EVT.

CONCLUSIONS

Simpler imaging selection criteria that rely on little else than detection of the occluded blood vessel may be more sensitive and less specific, thus resulting in more patients being offered EVT and arguably benefiting from it.

Monocyte-to-Lymphocyte Ratio in Clot Analysis as a Marker of Cardioembolic Stroke Etiology

The aim of the study was to find markers of high-risk cardioembolic etiology (HRCE) in patients with cryptogenic strokes (CS) through the analysis of intracranial clot by flow cytometry (FC). A prospective single-center study was designed including patients with large vessel occlusion strokes. The percentage of granulocytes, monocytes, lymphocytes, and monocyte-to-lymphocyte ratio (MLr) were analyzed in clots extracted after endovascular treatment (EVT) and in peripheral blood. Large arterial atherosclerosis (LAA) strokes and high-risk cardioembolic (HRCE) strokes were matched by demographics and acute reperfusion treatment data to obtain FC predictors for HRCE. Multilevel decision tree with boosting random forest classifiers was performed with each feature importance for HRCE diagnosis among CS. We tested the validity of the best FC predictor in a cohort of CS that underwent extensive diagnostic workup. Among 211 patients, 178 cases underwent per-protocol workup. The percentage of monocytes (OR 1.06, 95% CI 1.01-1.11) and MLr (OR 1.83, 95% CI 1.12-2.98) independently predicted HRCE diagnosis when LAA clots (n = 28) were matched with HRCE clots (n = 28). Among CS (n = 82), MLr was the feature with the highest weighted importance in the multilevel decision tree as a predictor for HRCE. MLr cutoff point of 1.59 yield sensitivity of 91.23%, specificity of 44%, positive predictive value of 78.79%, and negative predictive value of 68.75 for HRCE diagnosis among CS. MLr ≥ 1.6 in clot analysis predicted HRCE diagnosis (OR, 6.63, 95% CI 1.85-23.71) in a multivariate model adjusted for age. Clot analysis by FC revealed high levels of monocyte-to-lymphocyte ratio as an independent marker of cardioembolic etiology in cryptogenic strokes.

Impact of COVID-19 Infection on the Outcome of Patients With Ischemic Stroke

Supplemental Digital Content is available in the text.

We evaluated whether stroke severity, functional outcome, and mortality are different in patients with ischemic stroke with or without coronavirus disease 2019 (COVID-19) infection.

Direct to Angiography Suite Without Stopping for Computed Tomography Imaging for Patients With Acute Stroke: A Randomized Clinical Trial

Importance

Direct transfer to angiography suite (DTAS) for patients with suspected large vessel occlusion (LVO) stroke has been described as an effective and safe measure to reduce workflow time in endovascular treatment (EVT). However, it is unknown whether DTAS improves long-term functional outcomes.

Objective

To explore the effect of DTAS on clinical outcomes among patients with LVO stroke in a randomized clinical trial.

Design, Setting, and Participants

The study was an investigator-initiated, single-center, evaluator-blinded randomized clinical trial. Of 466 consecutive patients with acute stroke screened, 174 with suspected LVO acute stroke within 6 hours of symptom onset were included. Enrollment took place from September 2018 to November 2020 and was stopped after a preplanned interim analysis. Final follow-up was in February 2021.

Interventions

Patients were randomly assigned (1:1) to follow either DTAS (89 patients) or conventional workflow (85 patients received direct transfer to computed tomographic imaging, with usual imaging performed and EVT indication decided) to assess the indication of EVT. Patients were stratified according to their having been transferred from a primary center vs having a direct admission.

Main Outcomes and Measures

The primary outcome was a shift analysis assessing the distribution of the 90-day 7-category (from 0 [no symptoms] to 6 [death]) modified Rankin Scale (mRS) score among patients with LVO whether or not they received EVT (modified intention-to-treat population) assessed by blinded external evaluators. Secondary outcomes included rate of EVT and door-to-arterial puncture time. Safety outcomes included 90-day mortality and rates of symptomatic intracranial hemorrhage.

Results

In total, 174 patients were included, with a mean (SD) age of 73.4 (12.6) years (range, 19-95 years), and 78 patients (44.8%) were women. Their mean (SD) onset-to-door time was 228.0 (117.9) minutes, and their median admission National Institutes of Health Stroke Scale score was 18 (interquartile range [IQR], 14-21). In the modified intention-to-treat population, EVT was performed for all 74 patients in the DTAS group and for 64 patients (87.7%) in the conventional workflow group (P = .002). The DTAS protocol decreased the median door-to-arterial puncture time (18 minutes [IQR, 15-24 minutes] vs 42 minutes [IQR, 35-51 minutes]; P < .001) and door-to-reperfusion time (57 minutes [IQR, 43-77 minutes] vs 84 minutes [IQR, 63-117 minutes]; P < .001). The DTAS protocol decreased the severity of disability across the range of the mRS (adjusted common odds ratio, 2.2; 95% CI, 1.2-4.1; P = .009). Safety variables were comparable between groups.

Conclusions and Relevance

For patients with LVO admitted within 6 hours after symptom onset, this randomized clinical trial found that, compared with conventional workflow, the use of DTAS increased the odds of patients undergoing EVT, decreased hospital workflow time, and improved clinical outcome.

Trial Registration

ClinicalTrials.gov Identifier: NCT04001738.

SARS-CoV-2 and Stroke Characteristics: A Report From the Multinational COVID-19 Stroke Study Group

Supplemental Digital Content is available in the text.

Background and Purpose:

Stroke is reported as a consequence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection in several reports. However, data are sparse regarding the details of these patients in a multinational and large scale.

Methods:

We conducted a multinational observational study on features of consecutive acute ischemic stroke, intracranial hemorrhage, and cerebral venous or sinus thrombosis among SARS-CoV-2–infected patients. We further investigated the risk of large vessel occlusion, stroke severity as measured by the National Institutes of Health Stroke Scale, and stroke subtype as measured by the TOAST (Trial of ORG 10172 in Acute Stroke Treatment) criteria among patients with acute ischemic stroke. In addition, we explored the neuroimaging findings, features of patients who were asymptomatic for SARS-CoV-2 infection at stroke onset, and the impact of geographic regions and countries’ health expenditure on outcomes.

Results:

Among the 136 tertiary centers of 32 countries who participated in this study, 71 centers from 17 countries had at least 1 eligible stroke patient. Of 432 patients included, 323 (74.8%) had acute ischemic stroke, 91 (21.1%) intracranial hemorrhage, and 18 (4.2%) cerebral venous or sinus thrombosis. A total of 183 (42.4%) patients were women, 104 (24.1%) patients were <55 years of age, and 105 (24.4%) patients had no identifiable vascular risk factors. Among acute ischemic stroke patients, 44.5% (126 of 283 patients) had large vessel occlusion; 10% had small artery occlusion according to the TOAST criteria. We observed a lower median National Institutes of Health Stroke Scale (8 [3–17] versus 11 [5–17]; P=0.02) and higher rate of mechanical thrombectomy (12.4% versus 2%; P<0.001) in countries with middle-to-high health expenditure when compared with countries with lower health expenditure. Among 380 patients who had known interval onset of the SARS-CoV-2 and stroke, 144 (37.8%) were asymptomatic at the time of admission for SARS-CoV-2 infection.

Conclusions:

We observed a considerably higher rate of large vessel occlusions, a much lower rate of small vessel occlusion and lacunar infarction, and a considerable number of young stroke when compared with the population studies before the pandemic. The rate of mechanical thrombectomy was significantly lower in countries with lower health expenditures.

Posterior reversible encephalopathy syndrome (PRES) associated with COVID-19

The novel human coronavirus disease (COVID-19) has been associated with vascular and thrombotic complications, some of which may result from endothelial dysfunction, including the posterior reversible encephalopathy syndrome (PRES). We report a case series of 8 patients with COVID-19 and PRES diagnosed at two academic medical centers between March and July of 2020. The clinical, laboratory and radiographic data, treatment, and short-term outcomes were retrospectively analyzed. The mean age was 57.9 ± 12 years, and 50% were women. Four patients had previous vascular comorbidities. All the patients suffered from severe pneumonia, requiring intensive care unit admission. Five patients were not hypertensive at presentation (all SBP < 127 mmHg). Neurologic symptoms included seizures in 7 patients; impaired consciousness in 5 patients; focal neurological signs in 3 patients; and visual disturbances in 1 patient. All patients underwent brain magnetic resonance imaging which indicated asymmetric T2 prolongation or diffusion changes (50%), extensive fronto-parieto-occipital involvement (25%), vascular irregularities (12.5%) and intracranial hemorrhage (25%). Four patients were treated with tocilizumab. Three patients were discharged without neurologic disability, 2 patients had persistent focal neurologic deficits and 2 expired. One patient's prognosis remains guarded. Together, these data support the relationship between PRES and endothelial dysfunction associated with severe COVID-19. In patients with severe COVID-19, PRES can be triggered by uncontrolled hypertension, or occur independently in the setting of systemic illness and certain medications. Like other infectious processes, critically ill patients with COVID-19 may be at greater risk of PRES because of impaired vasoreactivity or the use of novel agents like Tocilizumab.