Early vs late anticoagulation in acute ischemic stroke with indications outside atrial fibrillation

BACKGROUND

Current literature lacks guidance on the safety of administering anticoagulation in acute ischemic stroke with emergent indications that require anticoagulation other than atrial fibrillation. Therefore, we tend to rely on studies investigating acute ischemic stroke in atrial fibrillation for anticoagulation recommendations.

METHODS

We retrospectively reviewed data for patients with acute ischemic stroke who had a non-atrial fibrillation emergent indication for anticoagulation (e.g., intra-arterial thrombus, intracardiac thrombus, acute coronary syndrome, acute limb ischemia, deep vein thrombosis and pulmonary embolism) diagnosed within 3 days of acute ischemic stroke. Patients who received anticoagulation ≤ 3 days of stroke onset (Group A) were compared to those who either received it afterwards or did not receive it at all (Group B).

RESULTS

Out of the 558 patients, only 88 patients met our inclusion criteria. Of the total cohort, 55.7 % patients were males, and basic demographics were similar in both groups except for milder strokes in Group A (national institute of health stroke scale 6 vs. 12.5, p = 0.03). Only 2 patients in Group A and 1 patient in Group B developed intracranial hemorrhage, which was not statistically significant. Group A patients had a lower incidence of both new diagnosis (2 % vs. 34.2 % %, p < 0.001) and propagation of an established venous thromboembolism. They also had a lower rate of any thromboembolic complication (2 % vs. 42 %, p < 0.001).

CONCLUSION

Early anticoagulation (i.e., ≤ 3 days) in non-atrial fibrillation ischemic stroke patients with an emergent indication may be safe and carry a lower risk of thromboembolic complications than later anticoagulation.

Single-centre study surveying neurology trainees' and faculty's perceptions of the impact of the COVID-19 pandemic on residents' medical education

Objective

To assess perceptions of our neurology residents and faculty regarding training experience and medical education during the early COVID-19 pandemic.

Methods

We distributed two online, voluntary and anonymous surveys to trainees and teaching faculty of our Neurology Department at Henry Ford Hospital. Surveys inquired about trainees’ stress, well-being, clinical experience and satisfaction with medical education and available support resources during the first wave of the COVID-19 pandemic in Michigan (mid-March to June 2020).

Results

A total of 17/31 trainees and 25/42 faculty responded to the surveys. Eight (47%) trainees reported high stress levels. Nine (57%) were redeployed to cover COVID-19 units. Compared with non-redeployed trainees, redeployed residents reported augmented medical knowledge (89% vs 38%, p=0.05). There was no difference in the two groups regarding overall satisfaction with residency experience, stress levels and didactics attendance. Twenty-one (84%) faculty felt that the redeployment interfered with trainees education but was appropriate, while 10 (59%) trainees described a positive experience overall. Both trainees and faculty believed the pandemic positively impacted trainees’ experience by increasing maturity level, teamwork, empathy, and medical knowledge, while both agreed that increased stress and anxiety levels were negative outcomes of the pandemic. Twelve (70%) trainees and 13 (52%) faculty were interested in pursuing more virtual didactics in the future.

Conclusion

Our findings provide an objective assessment of residents' experience during the COVID-19 pandemic and can guide teaching programmes in their medical education response in the face of future global crises.

Impact of the COVID-19 Pandemic on Acute Stroke Care, Time Metrics, Outcomes, and Racial Disparities in a Southeast Michigan Health System

BACKGROUND

COVID-19 has impacted acute stroke care with several reports showing worldwide drops in stroke caseload during the pandemic. We studied the impact of COVID-19 on acute stroke care in our health system serving Southeast Michigan as we rolled out a policy to limit admissions and transfers.

METHODS

in this retrospective study conducted at two stroke centers, we included consecutive patients presenting to the ED for whom a stroke alert was activated during the period extending from 3/20/20 to 5/20/20 and a similar period in 2019. We compared demographics, time metrics, and discharge outcomes between the two groups.

RESULTS

of 385 patients presented to the ED during the two time periods, 58% were African American. There was a significant decrease in the number of stroke patients presenting to the ED and admitted to the hospital between the two periods (p <0.001). In 2020, patients had higher presenting NIHSS (median: 2 vs 5, p = 0.012), discharge NIHSS (median: 2 vs 3, p = 0.004), and longer times from LKW to ED arrival (4.8 vs 9.4 h, p = 0.031) and stroke team activation (median: 10 vs 15 min, p = 0.006). In 2020, stroke mimics rates were lower among African Americans. There were fewer hospitalizations (p <0.001), and transfers from outside facilities (p = 0.015).

CONCLUSION

a trend toward faster stroke care in the ED was observed during the pandemic along with dramatically reduced numbers of ED visits, hospitalizations and stroke mimics. Delayed ED presentations and higher stroke severity characterized the African American population, highlighting deepening of racial disparities during the pandemic.

Abstract P156: Impact of Covid-19 on Thrombolysis and Thrombectomy Time Metrics at Henry Ford Hospital’s Detroit and West Bloomfield Campuses

Background: We propose that social distancing policies during COVID-19 may have negatively impacted the timely administration of intravenous tPA and mechanical thrombectomy (MT) in acute ischemic strokes (AIS).

Methods: In this retrospective study conducted at 2 large stroke centers serving Southeast Michigan, we included consecutive patients admitted to our stroke unit from 3/20/20 to 5/20/20 (COVID) and a similar epoch in 2019 (pre-COVID). We compared demographics and time metrics.

Results: 247 patients with AIS were included in the tPA analysis, 167 (68%) in 2019 vs 80 (32%) in 2020. Overall mean age was 67.2, 60% male and 49% African Americans (AA). tPA was given in 13/80 in 2019 vs 17/167 patients in 2019 (16% vs 10%, p=0.143). There was no difference in tPA rates between AA and non-AA in 2020. There was a trend toward faster tPA administration in 2020 vs 2019 (median: 37.8 vs 51 min, p=0.051), significant among AA (37.8 vs 58.8 min, p=0.029). Mild/rapidly improving strokes was less frequently a tPA exclusion in 2020 vs 2019 (0% vs 10%). Delayed presentation was significantly less frequent among non-AA in 2020 vs 2019 (54% vs 66%, p=0.045) but there was a trend toward more frequent delayed presentations in AA vs non-AA in 2020 (76 vs 54%, P=0.073). 69 patients were eligible to receive MT, 42 (61%) in 2019 and 27 (39%) in 2020. Mean age was 67.9 and 36% were AA. No differences were detected between 2019 and 2020 in MT rates or time metrics. In 2020, there was a slight trend toward lower MT rates for AA vs non-AA patients (69% vs 30%, p=0.10).

Conclusion: During the COVID-19 pandemic in Detroit there was a trend toward faster tPA administration compared to the same period pre-COVID, especially among AA. There was no significant difference in MT rates or time metrics. In our AA-majority city, there was a trend towards more delayed presentations and lower MT rates among AA during COVID. The reasons for these differences are yet to be determined and warrant further research.

Abstract P377: Real-Word Performance of Two Automated Software Platforms for Large-Vessel Occlusion Identification in Acute Ischemic Stroke Patients: A Single Center Experience

Background and purpose: Modern stroke treatment has been revolutionized by image-guided selection of patients for endovascular thrombectomy. Current automated platforms allow for real-time identification of large vessel occlusion and salvageable brain tissue. We had previously demonstrated that a “CTA for all” policy for stroke patients immediately upon arrival assists in the earlier identification of treatment candidates. We now sought to evaluate the performance of these platforms under this policy.

Methods: All patients that presented to Henry Ford Health System hospitals over a period of 6 weeks received CTA of the head and neck upon initial presentation. The images were processed with two automated software platforms. We prospectively collected processing times, large-vessel-occlusion alerts, performance warnings, and LVO density ratios. We compared these with the interpretations of board-certified radiologists, and analyzed the performance of each platform.

Results: 276 patients presented with stroke symptoms and received CT angiography upon presentation. Both platforms were able to image all stroke patients within their FDA-approved indications. Both platforms were noted to have comparable sensitivity, specificity, PPV and NPV, and excellent accuracy. The overall prevalence of LVO was extremely low (8/276). As a result, for both, NPV was much better than PPV because of the percentage of false positive results. Further ROC analysis, demonstrated an area under the ROC curve of 0.982, and overall model quality of 0.97. Optimal LVO density cutoff was <0.093 in order to maximize overall accuracy, or < 0.271, in order to maintain a sensitivity of 100% as an absolute priority (both significantly lower than the current threshold of <0.45).

Conclusions: Automated software platforms are an invaluable aid in the selection of patients for endovascular thrombectomy. Different LVO detection algorithmic thresholds may be necessary (and should be part of individual stroke center validation pathways) to avoid fatigue alert, and optimize test accuracy, when LVO prevalence is low. Stroke teams should be aware of the limitations of automated analysis and need for expert review.

Abstract P405: A Time-Series Forecast Model to Assess Vital Sign Waveform Variability Prior to Vasospasm

Introduction: Symptomatic vasospasm (SV) is a complication of aneurysmal subarachnoid hemorrhage (aSAH) and can lead to cerebral infarction. Changes in vital trends, such as heart rate (HR) and mean arterial blood pressure (MAP), have been associated with SV in aSAH. Real-time assessment of instantaneous vital sign waveform data could improve detection of vital sign variability associated with vasospasm. However, no model using instantaneous waveform data exists to predict SV. We hypothesize that autoregressive integrated moving average (ARIMA) analysis, a time-series forecast model, is a useful approach to assess the variability of vital sign waveforms associated with SV.

Methods: In this small case-control study, vital signs of patients admitted to the neuroICU with aSAH were obtained using a software-based analytics platform, Sickbay. HR and MAP from 15 aSAH patients were continuously obtained from ECG and arterial line waveforms. Ten patients developed neurologic deficits attributed to angiographically-confirmed SV (Det). Five controls (Con) without SV were matched based on age. 3 Det and 3 Con were randomly selected for further analysis. For Det, waveforms were analyzed at 5-second intervals for 48 hours prior to clinical deterioration. For Con, waveforms were analyzed at a random 48-hour interval.

Results: Visually, MAP and not HR was more variable in Det than in Con patients (Figure). The ARIMA model plotted the forecasted-fit for each delta-variable waveform. The MAP confidence interval margins were significantly larger for Det patients compared to the Con patient. This trend was consistent across all other patients.

Conclusion: ARIMA is a useful tool to assess HR and MAP waveform variations prior to SV in aSAH. Larger studies are required to solidify this concept and further explore the combination of data analytics platform and ARIMA to predict neurological deterioration in SV.

Tales of a department: how the COVID-19 pandemic transformed Detroit's Henry Ford Hospital, Department of Neurology-part I: the surge

The COVID-19 pandemic has reshaped the way healthcare systems operate around the world. The major hurdles faced have been availability of personal protective equipment, intensive care unit beds, ventilators, treatments and medical personnel. Detroit, Michigan has been an epidemic ‘hotspot’ in the USA with Wayne County among the hardest hit counties in the nation. The Department of Neurology at Henry Ford Hospital, in the heart of Detroit, has responded effectively to the pandemic by altering many aspects of its operations. The rapid engagement of the department and enhanced utilisation of teleneurology were two of the pivotal elements in the successful response to the pandemic. In this review, we describe the transformation our department has undergone, as it relates to its infrastructure redesigning, coverage restructuring, redeployment strategies, medical education adaptations and novel research initiatives.

Abstract WMP83: Bidirectional Brain-Microbiome Interaction in a Murine Thrombotic Stroke Model

Introduction: Recent evidence suggests a role of the gut microbiome in modulating the secondary injury seen after an ischemic stroke. In a novel model of thrombotic stroke in mice, the collagen model, we hypothesized that (a) stroke induces changes in the composition of the microbiome, and (b) depletion of the gut flora with cefoxitin is associated with a reduced infarct size.

Methods: C57BL/6 male mice were assigned to one of 4 groups (n=8/group): Control, Stroke (anesthesia, ICA cannulation, collagen injection into the MCA), Sham (same as Stroke without collagen injection), and Stroke+Antibiotic. Cefoxitin was administered in drinking water for 7 days, before stroke induction. Stool pellets were collected before surgery and on the day of euthanasia for taxonomic analysis via 16S rRNA sequencing. Brains were retrieved for infarct volume measurement 2 days after surgery.

Results: We observed a significant decrease in Lactobacillus and relative increases in Bacteroides, Streptococcus and Clostridium taxa after surgery in both Sham and Stroke groups (Fig 1). Antibiotic treatment was associated with a significant reduction in infarct volume in cortex and striatum (respectively 36.9% and 17.8% reductions, p<0.05) (Fig 2).

Conclusions: Thrombotic stroke in mice is associated with significant changes in the relative preponderance of several bacterial taxa in the gut. Intriguingly, a similar pattern was observed in sham animals, indicating effects on the microbiome not mediated by stroke, possibly by exposure to anesthetic drugs or surgery itself. Cefoxitin administered prior to stroke dramatically altered the gut microbiome and led to a significant reduction in infarct size.