Evaluation of Collateral Circulation in Patients with Acute Ischemic Stroke

The cerebral collateral circulation is an increasingly important consideration in the management of acute ischemic stroke and is a key determinant of outcomes. Growing evidence has demonstrated that better collaterals can predict the rate of infarct progression, degree of recanalization, the likelihood of hemorrhagic transformation and various therapeutic opportunities. Collaterals can also identify those unlikely to respond to reperfusion therapies, helping to optimize resources. More randomized trials are needed to evaluate the risks and benefits of endovascular reperfusion with consideration of collateral status. This reviews our current understanding of the pathophysiologic mechanisms, effect on outcomes and strategies for improvement of the collateral system.

Abstract WP20: Patterns Of Alert And Management Of Cerebral Aneurysms Using An Incidental Aneurysm Alert System

Introduction: Incidentally discovered cerebral aneurysms are increasingly common as patients are more frequently imaged. To aid in this management, we developed an aneurysm alert system. Here we describe the effectiveness and outcomes of our Incidental Aneurysm Alert System (IAAS).

Methods: IAAS received MRA and CTA reports from our Radiology department. Reports were parsed using natural language processing to identify ‘aneurysm’, automatically generating alerts for the interventional neuroradiologists. Background demographics, referral patterns, risk factors and management were then assessed.

Results: From March to December 2020, 145 consecutive reports were reviewed. A 87% cerebral aneurysm detection accuracy rate resulted after excluding duplicates and non-vascular lesions, resulting in 117 unique cases. Median age was 65 and 65% were female. Most frequent races were 53% non-Hispanic White, 19% other, 9% Asian, 6% Black; 26% were of Hispanic ethnicity. The most common indication was acute stroke (29%). Of the detected aneurysms, 49% resulted in consultation with an interventionalist. Neurology was the most common referring specialty (37%). Of those referred, 49% underwent diagnostic and/or therapeutic angiography. Sixty eight percent who underwent cerebral angiography were intervened upon immediately or within 2 years of discovery. Seven percent were ruptured on discovery. Aneurysms were most frequently treated with flow diversion (37%), coiling (37%), and clipping (16%).Mean PHASES score of referred patients was 4.3, conferring 0.9-1.3% 5-year rupture risk. Asians and Hispanics had higher PHASES scores on presentation of 6.1 (1.7% 5-year rupture risk) and 5.2 (1.3% 5-year rupture risk) respectively, compared to Non-Hispanic Caucasians of 3.8 (0.9% 5-year rupture risk). For Hispanics, mean age was 55 and mean aneurysm size 9.8 mm as compared to 66 and 5.6 mm in non-Hispanic Caucasians. There were no significant differences in aneurysm risk factors.

Conclusions: IAAS is an effective alerting system. Hispanics were younger with larger aneurysms on detection. IAAS may have potential value in connecting general physicians with cerebrovascular specialists, improving the management of incidentally discovered cerebral aneurysms.

Utility of tPA Administration in Acute Treatment of Internal Carotid Artery Occlusions

Background

Intravenous tissue plasminogen activator (IV-tPA) remains part of the guidelines for acute ischemic stroke treatment, yet internal carotid artery occlusions (ICAO) are known to be poorly responsive to IV-tPA. It is unknown whether bridging thrombolysis (BT) is beneficial in such cases.

Purpose

We sought to evaluate whether the use of IV-tPA improved overall clinical outcomes in patients undergoing endovascular thrombectomy (EVT) for ICA occlusions.

Methods

Data from 1367 consecutive stroke cases treated with EVT from 2012-2019 were prospectively collected from a single center. Univariate and multivariate logistic regression were used to assess the relationship between IV-tPA administration and clinical outcome.

Results

153 patients were found to have carotid terminus and tandem ICAO who received EVT and presented within 4.5h of last seen well. 50% (n = 82) received IV tPA. There were no differences between the groups with respect to age, NIHSS, time to EVT and ASPECTS score. 53% had tandem ICA-MCA occlusions. Rate of recanalization (≥ TICI 2B) and sICH did not significantly differ between the two groups. Regression analysis demonstrated no effect of IV-tPA on modified Rankin Score (mRS) at 90 days and overall mortality. Factors significantly associated with reduced mortality included lower age, lower NIHSS, and better rate of recanalization.

Conclusions

There was no significant difference in clinical outcomes in those receiving BT vs. direct EVT for ICAO. For centers with optimal door-to-puncture times, bypassing IV-tPA may expedite recanalization times and potentially yield more favorable outcomes. Patients with higher NIHSS and tandem lesions may have better outcomes with BT.

Abstract WMP116: Multi-center Assessment of Morbidity After Cerebral Arteriovenous Malformation Rupture

Background: Previously published single center studies suggest the morbidity associated with brain arteriovenous malformations (AVM) hemorrhage to be lower than assumed. Given the recent controversy over the appropriate management of unruptured brain AVMs, we performed a multi-center critical assessment of the morbidity associated with ruptured brain AVMs.

Methods: A retrospective chart review from tertiary care, urban, academic medical centers was performed. Inclusion criteria consisted of patients admitted for intracranial hemorrhage caused by a previously untreated AVM. Thirty-seven variables were analyzed, including patient demographics, imaging findings, clinical course and clinical exams.

Results: 101 patients from three medical centers dating from 2008-2014 met the inclusion criteria. Admission NIHSS scores of 0, 1-9 and ≥10 were 26%, 29% and 45% respectively. Hematoma location was parenchymal in 32%, intraventricular in 11%, subarachnoid in 5%, and combined in 52%. Deep venous drainage was present in 43% of cases, and associated aneurysms were present in 44%. Thirty-seven percent underwent emergent hematoma evacuation while 8 patients expired during their admission. At discharge, of those that survived, 69% had a NIHSS ≥ 1, and 23% had a NIHSS ≥ 10. At 90 day follow-up, 27% had a mRS ≥ 3. Patients with admission NIHSS ≥ 10 had significantly higher rates of midline shift, surgical hematoma evacuation, and follow-up mRS ≥ 3( p < 0.05).

Conclusion: This multicenter critical assessment of the morbidity associated with brain AVM rupture suggests poorer clinical outcomes than previously assumed and reported. Rupture morbidity should be considered alongside rupture risk and procedural risk when considering preventative anatomic treatment of unruptured brain AVMs.

A Prospective Comparison of Informant-based and Performance-based Dementia Screening Tools to Predict In-Hospital Delirium

Dementia is an important risk factor for delirium, but the optimal strategy for incorporating cognitive impairment into delirium risk assessment at the time of hospital admission is unknown. We compared 2 informant-based screening tools for dementia and mild cognitive impairment [AD8 and D=(MC)] to the Mini Mental State Examination (MMSE) and Mini-cog in predicting hospital-acquired delirium. This prospective cohort study at an academic medical center consisted of 162 medical inpatients over age 50 years without delirium upon admission. Each participant was evaluated using the MMSE, Mini-cog, AD8, and D=(MC) upon admission and was assessed daily for delirium. An MMSE≤24 carried a 5.5 [95% confidence intervals (CI), 2.7-11.1] relative risk for delirium, whereas cognitive impairment detected by the Mini-cog, D=(MC), or AD8 carried a 2-fold risk. Adding the D=(MC) to the MMSE increased the sensitivity for predicting delirium from 52% (range, 32% to 73%) for the MMSE alone to 65% (range, 46% to 85%) if either test was positive. If both were positive, specificity was maximized at 97% (range, 94% to 100%), but sensitivity was 17% (range, 2% to 33%). The MMSE and Mini-cog identify a large proportion of patients at risk for hospital-acquired delirium, but the combination of performance-based and an informant-based screens may maximize specificity and sensitivity.

Abstract T P356: Predictors of Depression 6 Months After Aneurysmal Subarachnoid Hemorrhage

Background: Functional outcome is of increasing importance among survivors of aneurysmal subarachnoid hemorrhage (SAH). Depression is commonly reported after stroke and may play a significant role in functional recovery after SAH. Our goal was to determine the prevalence and predictors of depression among survivors of SAH at 6 months.

Methods: Six-month follow up data was analyzed from a cohort study of SAH patients at a tertiary care center. With IRB approval and consent, patients completed serial 6-month outcome assessments including the Modified Rankin Scale (mRS) and the Hospital Anxiety and Depression Scale (HADS). Independent predictors of poor functional (mRS>2) and mood outcomes (HADS≥10) were determined using univariate and multivariate statistics.

Results: Of 247 subjects (74% female, mean age 55), 7% had poor functional outcome. Depression was reported in 17%. Poor functional outcome was significantly associated with a longer hospitalization (mean 26 days, p=0.02), placement of an EVD and VP shunt (p=0.008 & 0.02) and antibiotic use (p=0.001). Depression was significantly associated with poor functional outcome, prior history of depression, and vasospasm (p=0.001, 0.004 & 0.05). Depression showed a trend in those who received an EVD, ventilator, and antibiotics. Depression was not significantly associated with treatment modality. Multivariate logistic analyses demonstrated that poor functional outcome (OR=5.25, CI=1.44-19.10, p=0.01), history of depression (OR=7.66, CI=1.87-31.45, p=0.005), and vasospasm (OR=2.65, CI=1.04-6.75, p=0.04) remain significant predictors of depression, however, EVD, ventilator, antibiotics, and Hunt Hess Grade are not significant.

Conclusion: Depression is not uncommon after SAH, and highly associated with poor neurological recovery at 6 months. Risk factors for development of depression include prior history of depression and cerebral vasospasm. Based on these results, we recommend screening for depression and consideration for early treatment for patients at highest risk after SAH.

The AWOL tool: derivation and validation of a delirium prediction rule

BACKGROUND

Risk factors for delirium are well-described, yet there is no widely used tool to predict the development of delirium upon admission in hospitalized medical patients.

OBJECTIVE

To develop and validate a tool to predict the likelihood of developing delirium during hospitalization.

DESIGN

Prospective cohort study with derivation (May 2010-November 2010) and validation (October 2011-March 2012) cohorts.

SETTING

Two academic medical centers and 1 Veterans Affairs medical center.

PATIENTS

Consecutive medical inpatients (209 in the derivation and 165 in the validation cohort) over age 50 years without delirium at the time of admission.

MEASUREMENTS

Delirium assessed daily for up to 6 days using the Confusion Assessment Method.

RESULTS

The AWOL prediction rule was derived by assigning 1 point to each of 4 items assessed upon enrollment that were independently associated with the development of delirium (Age ≥ 80 years, failure to spell "World" backward, disOrientation to place, and higher nurse-rated iLlness severity). Higher scores were associated with higher rates of delirium in the derivation and validation cohorts (P for trend < 0.001 and 0.025, respectively). Rates of delirium according to score in the combined population were: 0(1/50, 2%), 1(5/141, 4%), 2(15/107, 14%), 3(10/50, 20%), and 4(7/11, 64%) (P for trend < 0.001). Area under the receiver operating characteristic curve for the derivation and validation cohorts was 0.81 (0.73-0.90) and 0.69 (0.54-0.83) respectively.

CONCLUSIONS

The AWOL prediction rule characterizes medical patients' risk for delirium at the time of hospital admission and could be used for clinical stratification and in trials of delirium prevention.