Post Thrombectomy Research Articles

Role of mechanical thrombectomy among large vessel stroke patients during the coronavirus disease (COVID-19) pandemic

PurposeThe aim of our study is to provide insights derived from experience at multiple centers regarding the outcomes of mechanical thrombectomy (MT) for large vessel occlusion (LVO) in COVID-19 patients and compare them with those in non-COVID-19 patients during the coronavirus disease (COVID-19) pandemic.ResultsCOVID‐19 positive patients were younger than COVID‐19 negative patients (62.1 ± 2.69 versus 69.5 ± 2.2, P < 0.001). There was a significant difference between COVID-19 and non-COVID-19 groups in the median D-dimer levels (6 vs. 4.5; P < 0.001), median ESR levels (63 vs. 38; P < 0.001) and median CRP levels (110 vs. 48.5; P < 0.001), respectively. Median time from stroke symptoms onset to hospital admission was significantly higher among COVID-19 positive patients (366 vs. 155 min; P < 0.001). COVID‐19 positive patients with LVO presented with a higher median NIH Stroke Scale score at presentation (16 versus 8, P < 0.001) and lower median Alberta Stroke Program Early CT Score (ASPECTS) on admission (6 versus 8, P < 0.001). Patients with COVID-19 had significantly higher percentages of poor functional outcomes as scored using the mRS grades 3–5 in comparison to non-COVID-19 patients (69.2% vs. 13.6%; P = 0.002), but there was no significant difference between both groups in complications such as early cerebral re-occlusion, intracerebral hemorrhage, or in-hospital mortality (P > 0.05).ConclusionMechanical thrombectomy has effectively managed patients with LVO stroke. LVO stroke in COVID-19 patients occur at a young age, and have multi-territory vascular involvement. Poor functional outcomes post thrombectomy in COVID-19 patients, irrespective of timely, successful angiographic recanalization.

Abstract TMP63: Blood Pressure (BP) Protocol Violations in IV Tenecteplase Treated Ischemic Stroke Patients is Associated With Early Neurologic Deterioration and Symptomatic Intracranial Hemorrhage

Background: The American Heart Association guidelines recommend BP goal of &lt;180/105 mmHg for the first 24 hours in acute ischemic stroke (AIS) patients treated with IV Alteplase and now adopted for IV Tenecteplase (TNK). Studies suggest increased hemorrhage risk in patients with BP ≥170 mmHg and greater BP variability. Methods: We performed a retrospective study with data from the Get with The Guidelines database and electronic medical record of all adult AIS patients treated with TNK at a Comprehensive Stroke Center from 6/2021 to 6/2023. All BP readings from ED arrival to 24 hours post TNK were queried. We analyzed the temporal trends of BP characteristics and their association with early neurological deterioration (END) and symptomatic intracranial hemorrhage (sICH). The BP characteristics included mean and standard deviation of systolic (SBP) and diastolic (DBP) measurements, intra-patient BP variability and frequency of excessive BP (SBP &gt; 180 mmHg and DBP &gt; 105 mmHg) at each time point. Results: There were 132 TNK treated patients: mean age 68 ± 15 years, 54% male, 73% Caucasian, median admission NIHSS 9, IQR 4-15, 42 (32%) underwent mechanical thrombectomy, 72 (54.5%) treated with IV antihypertensive(s). Of these, 6 (4.5%) developed END and another 6 (4.5%) sICH. Of the 5901 BP measurements, 217 (3.7%) and 99 (1.7%) exceeded systolic of &gt;180 mmHg and diastolic of &gt;105 mmHg respectively. All END and sICH patients had excessive BP within 4 hours post TNK (Figure 1) and during this time there was a strong association of END with excessive SBP (14% vs 4.8%; p=0.05) and DBP (14% vs 1.2%; p &lt; 0.001). sICH had a similar but weaker association: excessive SBP (7.7% vs 4.9%; p=0.3) and excessive DBP (3.8% vs 1.4%; p=0.2). Conclusion: Our findings suggest that excessive BPs within 4 hours of TNK may be associated with patients developing END and sICH. Further exploration of moderate BP parameters deserve further study post thrombolysis, like the BEST II study in post thrombectomy patients.

Abstract TP203: Effect of SARS-CoV2 Infection on Endovascular Thrombectomy Outcomes - Data From the Florida Stroke Registry

Introduction: The outcomes of endovascular thrombectomy (EVT) in SARS-CoV2 positive patients with acute ischemic stroke (AIS) are not well studied. In the large Florida Stroke Registry we compared in hospital and discharge outcomes of patients with target vessel occlusions treated endovascularly with versus without a SARS-CoV2 positive infection status during their hospitalization. Methods: Data from Get With the Guidelines-Stroke hospitals participating in the Florida Stroke Registry from March 2020 to December 2022 were reviewed. EVT patients with coding for SARS-CoV2 testing during their hospital stay were categorized into SARS-CoV2 positive or negative groups. Associations between SARS-CoV2 status and favorable EVT outcomes of good mRS (0-2) at discharge, discharge to home or to rehabilitation centre, and independent ambulation at discharge were examined using multivariate logistic regression modeling adjusting for demographics, vascular risk factors, and clinical characteristics with generalized estimating equations (GEE). Temporal analyses compared outcomes across the years 2020-2022. Results: A total of 8,778 patients underwent EVT, of these, 193 (2.25%) were SARS-CoV2 positive. The odds of mRS 0-2 and independent ambulation at discharge were OR 0.194 (CI 0.035,1.077) and OR 0.794 (CI 0.168,3.75) in SARS-CoV2 positive relative to negative EVT patients. Outcomes of mRS 0-2 (OR 0.194, CI 0.035,1.077) and ambulation at discharge (OR 0.794, CI 0.168,3.75) were shy of statistical significance. Accounting for baseline differences SARS-CoV2 positive patients were less likely to be discharged home or to a rehabilitation centre (OR 0.671, CI 0.488,0.921) in multivariable analysis with GEE. Temporal analysis of SARS-CoV2 positive patients showed no significant differences across the years studied. Conclusions: In this large muliticentre stroke registry the results suggest that favorable outcomes post thrombectomy may be negatively impacted by SARS-CoV2 infection. Temporal assessment showed similar results across the years studied. These findings provide novel insight from a large database to add to the emerging literature examining outcomes of concurrent SARS-CoV2 infection in the setting of EVT for target vessel occlusion AIS.

Good outcome in a rare presentation of simultaneous cerebral superficial and deep venous thrombosis with cortical vein thrombosis post thrombectomy: A case report

Good outcome in a rare presentation of simultaneous cerebral superficial and deep venous thrombosis with cortical vein thrombosis post thrombectomy: A case report

Abstract 12644: FlowTriever Percutaneous Aspiration Thrombectomy: A Promising Approach to Catch a (Throm)Bus In-Transit

Introduction: Clot-in-transit (CIT) is a life-threatening emergency that occurs in about 25,000 patients annually and is associated with high mortality due to rapid cardiopulmonary collapse. This is a case of right atrial (RA) CIT extending from existing IVC filter in a patient with pulmonary embolism (PE) who underwent successful FlowTriever® catheter-based thrombectomy. Description of Case: A 60-year-old male presented with progressively worsening dyspnea on exertion, generalized weakness and fatigue, intermittent chest pain, and right leg pain with immobility for several weeks. He had a history of deep vein thrombosis (DVT), PE in 2008 treated with 18-month of warfarin. IVC filter was placed at that time for unclear indication. His initial labs showed elevated troponin-I of 34 ng/mL and NT pro-BNP of 3542 pg/mL, atrial flutter with 2:1 conduction, incomplete right bundle branch block, and old inferior infarct on ECG. Imaging revealed an extensive bilateral PE with right ventricle (RV) to left ventricle (LV) ratio of 2.3. Transthoracic echocardiogram (TTE) showed global LV dysfunction with ejection fraction of 44%, RV strain, dilated IVC, and an 8.7-cm mobile CIT in IVC extending into RA. Despite being treated with Heparin infusion, patient remained persistently tachycardic and dyspneic. Given his clinical stagnation due to CIT and submassive PE, he underwent an invasive TTE-guided percutaneous IVC and pulmonary arterial thrombectomy using Inari FlowTriever® catheter. Repeated TTE showed complete resolution of atrial thrombus. There was improvement in pulmonary arterial pressure and symptoms immediately post thrombectomy, but atrial flutter persisted. He was eventually discharged the following day with betablocker and life-long duration of anticoagulation. At follow up, he had complete resolution of symptoms and normal sinus rhythm on ECG. Discussion: Although surgical embolectomy is considered first-line therapy, percutaneous thrombectomy should be considered early for CIT to prevent of cardiopulmonary deterioration and shorter hospital course. FlowTriever® is the first device not requiring a cardiopulmonary bypass circuit to be FDA cleared for RA CIT, particularly benefiting patients who are poor surgical candidates.

Abstract 222: Immediate post thrombectomy extubation is associated with improved clinical outcomes

Introduction Recent findings suggest that general anesthesia with endotracheal intubation (GA) in patients with acute ischemic stroke (AIS) due to large vessel occlusion (LVO) who receive mechanical thrombectomy (MT) is associated with similar outcomes to conscious sedation (CS). [1][2] However, these trials involved stroke specific GA protocols in which immediate, post‐operative extubation was emphasized. In this study, we investigated outcomes of MT in AIS due to LVO as a function of the timing of extubation and explored variables that could delay extubation. Methods We performed a retrospective analysis of collected data gathered during a 5‐year period (2018‐2022) for all our patients with AIS due to LVO who received MT. We analyzed the stroke outcomes and complications between patients who had received GA and those who had received CS. We also investigated the relationships between associated pulmonary risk factors, timing of extubation, and tracheostomy, on the outcomes of stroke. Results A total of 242 patients were included in our study. 83 patients received GA and 159 patients received CS. Our study shows CS in MT had a 2.74 (95% CI = 1.21‐6.22) higher odds of having a final TICI rating of 0‐2a compared to those who had GA. A logistic regression model was fitted that included NIHSS prior to MT; in this analysis, patients who received GA had 2.71 times higher odds of reaching TICI 2b or higher (OR = 2.71, 95% CI = 1.19‐6.17). NIHSS was not a significant predictor of recanalization in our patients. Patients extubated in the IR suite vs. elsewhere (excluding patients who were not extubated in hospital) had 3.82 (95% CI = 1.03‐14.18) times higher odds of having an excellent mRS at 90 days (n=65). Those extubated late had higher odds of transitioning to comfort care (OR=4.50, 95% CI = 1.52‐13.31, p=0.004), and 90‐day mortality (OR=5.49, 95% CI = 1.71‐17.65, p=0.002). Those who were extubated early had a lower NIHSS post MT (mean = 10.89 vs 19.18), t=‐5.79, p&lt;0.001), and a lower NIHSS at discharge (mean = 9.20 vs 17.11), t=‐5.79, p&lt;0.001). There were no significant correlations between history of COPD or the BMI and the timing of extubation or the outcomes of MT. In addition, COPD was not associated with any significant changes in discharge or 90 days mRS. Conclusion Administration of GA to patients who receive MT for AIS was associated with better outcomes in our cohort. Immediate extubation was associated with better outcomes than delayed extubation in the GA group. A history of COPD or high BMI should not affect the decision to provide with GA for MT.

Abstract Number ‐ 26: Results from Flat‐Panel CT as a predictor following Mechanical Thrombectomy

Introduction Flat‐panel CT provides quick and effective parenchymal cross‐sectional imaging. Pre‐thrombectomy, flat‐panel can be obtained to evaluate ischemic stroke patients for thrombectomy candidacy in cases where the traditional CT scanner is bypassed. Post‐thrombectomy images obtained from flat‐panel CT are also effective in evaluating complications such as contrast extravasation, hemorrhage, or increased core size. Findings on flat‐panel CT may provide information to guide decisions such as blood pressure goals, antiplatelet or anticoagulation regimen, thrombolytic reversal, and the need for emergent neurosurgical intervention in rare cases. Methods We analyzed 93 thrombectomy cases from 2021 to 2022, where flat‐panel CT was obtained, with follow‐up CT and MRI. Demographics were reviewed for this series of cases. Cases where stratified and compared depending on results on flat‐panel CT. Medical records were reviewed for changes in management. The local IRB approved the project, and consent was waived according to institutional guidelines. Results For our patient population, the median age was 70; race was 59% Caucasian, 40% African American, and 1% Hispanic; and gender was 46% female and 54% male. From the flat‐panel CT, we had the following results: Flat‐panel CT was normal in 68% of cases, 20% had contrast extravasation, 9% showed evidence of contrast extravasation vs. hemorrhage, 2% had hemorrhage during the procedure, and 1% had contrast retained in the vessels. On follow‐up CT, 35% had no change, 16% had contrast extravasation, 8% had SAH, 4% had contrast extravasation vs. hemorrhage, 3% had hemorrhagic transformation, 1% had IVH, 1% had petechial hemorrhages, and 31% had no follow‐up CT. On MRI, 20% had hemorrhagic transformation, 41% had no hemorrhage, 6% had microhemorrhages, 10% had petechial hemorrhages, 2% had ICH, 1% had 1 IVH, 1% had SAH, 1% had contrast extravasation, 17% of the cases had no follow‐up MRI. Based on flat‐panel CT, results for normal and contrast extravasation were as follows (Table 1.). Therapy was altered by the flat‐panel CT results in 10 cases. The main change in therapy was a delay in restarting antiplatelet and anticoagulation therapy, which took place in 9 cases. Conclusions Post thrombectomy flat‐panel CT is a useful screen post thrombectomy for high‐risk findings such as contrast extravasation and hemorrhagic transformation. Further studies are needed to determine ideal management in cases of contrast extravasation or hemorrhage on flat‐panel CT.

Abstract Number ‐ 34: Basal ganglia infarct volume and risk of hemorrhagic transformation after endovascular thrombectomy

Introduction As more large vessel occlusion stroke patients are treated with endovascular thrombectomy (EVT), understanding the pathophysiology of reperfusion injury and the risks of hemorrhagic transformation (HT) are increasingly important. Pre‐EVT infarct topography may have implications for acute interventional treatments such as stenting, and post thrombectomy care such as antithrombotic choice. We sought to quantify region‐specific volumes of infarcted tissue on pre‐EVT MRI, understand their importance for HT, and identify associations with clinical and imaging characteristics. Methods Patients with pre‐EVT MRI were identified retrospectively from a prospectively maintained database. Each patient’s diffusion weighted sequence underwent manual infarct delineation and was registered to a standard space for overlay with cortical, subcortical, and white matter atlases. Structure‐specific lesion volumes were determined. HT was defined as PH1 or PH2 hemorrhage by ECASS criteria. Variables with p&lt; 0.10 in univariate analyses were included in multivariable models. Logistic regression was performed for associations with hemorrhagic transformation and linear regressions for infarct volumes. Results 165 participants [median age 69 years (interquartile range, IQR 56–79), 56% women] were identified. Risk factors included hypertension (70%), diabetes (20%), atrial fibrillation (34%), and prior stroke/TIA (13%). 52% were treated with intravenous alteplase; 70% achieved TICI 2b‐3 reperfusion. HT occurred in 8%. Pre‐EVT infarct volumes [median (IQR)] were 22 cc (12‐43 cc) for total, 11 cc (6‐19 cc) for white matter, 5 cc (1‐19 cc) for cortex, and 3 cc (1‐6 cc) for basal ganglia. Pre‐EVT infarcts [median (IQR)] were made up of 48% (38‐60%) white matter, 23% (6‐47%) cortex, and 15% (4‐28%) basal ganglia. Paramagnetic sequences showed 3% had petechial hemorrhage and 40% had susceptibility vessel sign. Basal ganglia infarct volume was independently associated with HT (OR = 1.342, 95%CI = 1.002,1.797) in a model including white matter infarct volume, cortex infarct volume, smoking, and puncture‐recanalization time. Basal ganglia infarct volume was linked to susceptibility vessel sign (Beta = 0.233, p = 0.006) and NIHSS (Beta = 0.220, p = 0.012), when controlling for total infarct volume. Conclusions In this cohort, greater basal ganglia infarct volume was associated with a higher risk of hemorrhagic transformation, even when accounting for infarct volume in other regions. Susceptibility vessel sign was associated with basal ganglia infarct volume, which may be related to acute middle cerebral artery thrombus occlusion of perforators. These findings require further study in larger cohorts.

DEEP MOVEMENT: Deep learning of movie files for management of endovascular thrombectomy

ObjectivesTreatment and outcomes of acute stroke have been revolutionised by mechanical thrombectomy. Deep learning has shown great promise in diagnostics but applications in video and interventional radiology lag behind. We aimed to develop a model that takes as input digital subtraction angiography (DSA) videos and classifies the video according to (1) the presence of large vessel occlusion (LVO), (2) the location of the occlusion, and (3) the efficacy of reperfusion.MethodsAll patients who underwent DSA for anterior circulation acute ischaemic stroke between 2012 and 2019 were included. Consecutive normal studies were included to balance classes. An external validation (EV) dataset was collected from another institution. The trained model was also used on DSA videos post mechanical thrombectomy to assess thrombectomy efficacy.ResultsIn total, 1024 videos comprising 287 patients were included (44 for EV). Occlusion identification was achieved with 100% sensitivity and 91.67% specificity (EV 91.30% and 81.82%). Accuracy of location classification was 71% for ICA, 84% for M1, and 78% for M2 occlusions (EV 73, 25, and 50%). For post-thrombectomy DSA (n = 194), the model identified successful reperfusion with 100%, 88%, and 35% for ICA, M1, and M2 occlusion (EV 89, 88, and 60%). The model could also perform classification of post-intervention videos as mTICI < 3 with an AUC of 0.71.ConclusionsOur model can successfully identify normal DSA studies from those with LVO and classify thrombectomy outcome and solve a clinical radiology problem with two temporal elements (dynamic video and pre and post intervention).Key Points• DEEP MOVEMENT represents a novel application of a model applied to acute stroke imaging to handle two types of temporal complexity, dynamic video and pre and post intervention.• The model takes as an input digital subtraction angiograms of the anterior cerebral circulation and classifies according to (1) the presence or absence of large vessel occlusion, (2) the location of the occlusion, and (3) the efficacy of thrombectomy.• Potential clinical utility lies in providing decision support via rapid interpretation (pre thrombectomy) and automated objective gradation of thrombectomy outcomes (post thrombectomy).

Semi-automated mapping of occluded arterial segments in acute large vessel stroke from computed tomography angiography

Catheterisation of occluded artery is the most crucial step in the mechanical thrombectomy of large vessel occlusions. Being a blind procedure, potential major untoward events could be anticipated at this stage. In this study, we evaluated the feasibility of reconstruction of the occluded vascular segment from CT angiography, exploiting the attenuation difference between the clot and adjacent brain parenchyma. Twenty-five patients with large vessel occlusion who achieved TICI2B/3 recanalization were identified. The semi-automated reconstruction was done using an open-source 3D segmentation software by two observers. The generated arterial anatomy was categorized as congruent, if all the major arterial segments namely, internal carotid artery, M1 middle cerebral artery, bifurcation, and major divisions matched with post thrombectomy angiograms. The discrepancy of one or more than one arterial segment was classified as mild or total mismatch respectively. Congruent arterial mapping was possible in 88% and 92 % patients for observer 1 and observer 2 respectively, while mild mismatch was noted in two patients for both the observers. Mismatch mostly occurred in superior division for both observers(100% vs 66.6%). The interrater agreement was good (0.77) and the accuracy was not influenced by the length of the clot. The median time for reconstruction was 4 minutes for both the observers (p - 0.21). Delineation of the anatomy of the occluded major intracranial artery is possible and corresponds with the actual anatomy. It could be used as a guide during thrombectomy procedures.

Abstract P219: Effect Of Hypertension On Clinical Recovery After Stroke Thrombectomy

Title: Effect of hypertension on clinical recovery after stroke thrombectomy Objective: Our goal was to identify what vascular risk factors for stroke affect outcomes after mechanical thrombectomy. Methods: We retrospectively reviewed stroke thrombectomy patients at our comprehensive stroke center from June 2013 to August 2016. Patients were determined to have atrial fibrillation, hypertension, diabetes, or hyperlipidemia based on historical information pre-treatment or based on hospital records during their index hospitalization. All patients in our series achieved recanalization after thrombectomy defined as a Thrombolysis in cerebral infarction (TICI) score of 2b or higher. Our endpoint was mild to moderate disability at 90 days defined by the modified Rankin Scale (mRS) score of 2 or less. We performed a univariate analysis on the above covariates affecting clinical outcome and studies all variables with a p-value of &lt; 0.2 in a multivariate analysis to determine which independent variables affected outcome. Multi-variate analyses were performed separately for males and females. Results: We reviewed 288 stroke patients that underwent thrombectomy. The mean age was 69±15; NIHSS was 17±6; 36% (104 of 288) received t-PA and 42% (121 of 288) had a modified Rankin Score of &lt; 2. 42.7% (123 of 288) were females. From the entire group, 47.5% (137 of 288) had atrial fibrillation, 29% (83 of 288) had diabetes mellitus 68% (197 of 288) had hypertension, 38.5% (111 of 288) had hyperlipidemia and 16% (47 of 288) had a history of tobacco smoking. After considering positive univariates from above, our multivariate logistic regression model identified that not having hypertension [ OR 2.32, CI 1.01-5.41, p=0.05 ] predicted better outcome post thrombectomy procedure for males after a successful recanalization. Conclusion: Our analysis suggests that, for males, the odds of a positive outcome after a successful thrombectomy procedure is positively influenced when the patient is not hypertensive. No traditional risk factor appeared to influence the outcome in females. Further prospective study is required to validate these findings.

Abstract WP69: Prediction Of 90 Day Stroke Recovery In A Post-thrombectomy Population

Introduction: Treatments for stroke developed in the last decade, such as thrombectomy, have improved patient outcomes. However, these treatments do not guarantee stroke recovery and many patients still need additional treatment to recover. Identifying the expected degree of recovery would help inform patient planning and improve personalized care. Methods: Retrospective patient information from 54 emergent thrombectomy patients, including hemorrhagic infarction, and diffusion parameters from their clinical diffusion MRI scan (1.5T, 20 directions, b=2000, NEX=2) were analysed in a multivariable logistic regression with the outcome of identifying favorable outcomes, score 0-2, of their modified Rankin Score (mRS) at 90 days. Models using patient information and imaging data were generated and compared. Results: Using stepwise regression, gender and a 24 hour NIHSS score were identified as the best patient information for indicating mRS at 90 days, while mean difference of the ipsilesional and contralesional motor track regions for fractional anisotropy (FA), mean diffusivity (MD), and orientation dispersion index (ODI) were the best imaging indicators for mRS at 90 days. The model from a multivariable logistic regression analysis of patient information gave a predictive model with an area under the curve (AUC) of 0.83 and confidence interval (CI) of 0.69 to 0.93 whereas a model using patient imaging data had an AUC of 0.93 and CI of 0.83 to 0.98. Combining both patient information and imaging data produced a model with an AUC of 0.95 and CI of 0.86 to 0.98. Conclusions: Patient information, imaging data, and combined create models for a post-thrombectomy cohort with good AUCs ranging from 0.83 to 0.95 for prediction of 90 day mRS . This initial study shows promising results that these models can be predictive in a heterogeneous post thrombectomy population.

Abstract WP34: Bed Ahead Process Avoids The Thrombectomy Patient Boarding In Emergency Department

Background: University Hospitals Comprehensive Stroke Center (UH CSC) is an academic medical center with a dedicated 19 bed Neuroscience Intensive Care unit (NSU). As the only comprehensive stroke center in a 22 hospital system, the majority of ischemic stroke patients requiring a mechanical thrombectomy procedure are transferred to the UH CSC. A post thrombectomy patient requires intensive monitoring to assess for complications and is best cared for by highly trained neuro nurses in an intensive care environment. Lack of available NSU beds often resulted in these patients returning to the high volume emergency department with less than ideal staffing. The request for a NSU bed was not initiated until the thrombectomy procedure began delaying the chain of events that lead to an available NSU bed. Hypothesis: A proactive process that would initiate obtaining a NSU bed sooner would avoid these patients from boarding in the emergency department. Methods: Key stake holders from the stroke program, neurocritical care, emergency medicine, neuro interventional and the transfer center met in early 2019 to review data and quality concerns. An algorithm was developed and shared with all staff. Once the stroke faculty accepts a transfer of a potential thrombectomy patient, the new process includes notifying the NSU fellow and charge nurse to initiate making an open bed before the patient arrives to UH CSC. Results: In 2018, 48% of patients that underwent a mechanical thrombectomy returned to the emergency department. After the implementation of the new process the percentage of patients returning to the emergency department declined to 28% in 2019. In 2020 only 8% returned to the emergency department. The number of quality concerns significantly decreased. Conclusion: The bed ahead process initiated before a thrombectomy patient arrives at the comprehensive stroke center has been successful in avoiding returns to the emergency department and meeting our goal to achieve high quality patient outcomes and improve care efficiency.

Complications of Mechanical Thrombectomy in Acute Ischemic Stroke.

Multiple randomized clinical trials have supported the use of mechanical thrombectomy (MT) as standard of care in the treatment of large vessel occlusion acute ischemic stroke. Optimal outcomes depend not only on early reperfusion therapy but also on post thrombectomy care. Early recognition of post MT complications including reperfusion hemorrhage, cerebral edema and large space occupying infarcts, and access site complications can guide early initiation of lifesaving therapies that can improve neurologic outcomes. Knowledge of common complications and their management is essential for stroke neurologists and critical care providers to ensure optimal outcomes. We present a review of the available literature evaluating the common complications in patients undergoing MT with emphasis on early recognition and management.

Abstract P481: Time to Reperfusion Determines Clinical Outcomes Independent of Post Thrombectomy Infarct Volume

Introduction: Late time window thrombectomy trials demonstrated that good functional outcomes can be achieved up to 24 hours from stroke onset in Slow Progressors (small infarct volume and large penumbral volume). In this study, we aim to investigate whether early (&lt;6 hours) recanalization leads to superior functional outcomes compared to delayed recanalization (&gt;6 hours) amongst patients with similar 24-hour infarct volumes post thrombectomy. Methods: We performed a retrospective analysis of a prospectively maintained LVO stroke thrombectomy database across 3 comprehensive stroke centers. Demographic, clinical, radiological, and outcomes data were analyzed. Inclusion criteria were witnessed onset anterior circulation LVO [internal carotid or middle cerebral artery M1] strokes with a good baseline mRS score (0-1) having achieved success recanalization [mTICI 2b-3] and 24-hour infarct volume of ≤10 ml on CT head or MRI. Univariate and multivariate analysis of the impact of time to recanalization on clinical outcomes was performed. Results: Of the 499 LVO strokes undergoing thrombectomy, 30% (148) met inclusion criteria. Mean age was 70 ±14 and median NIHSS score was 17 (14-21). Early recanalization (&lt;6h) was achieved in 65% (96) of patients. Baseline demographic (age: 73 vs 74, p=0.80) and clinical characteristics (NIHSS:16.5 vs 17, p=0.52; 24-h infarct volume: 4.4 vs 4.2 ml, p=0.60) were comparable between early versus late recanalization patients. Rates of early clinical improvement (24-h NIHSS &lt;6) (71% vs 39%, p=0.0007) and mRS 0-2 at 90 days (68% vs 48%, p=0.019) were higher in early recanalizers compared to late recanalizers. Multivariate analysis including age, NIHSS, time to recanalization, and 24-hour infarct volume identified early recanalization as an independent predictor of mRS 0-2 at 90 days (OR-2.41 95% CI 1.89-4.50). Every 1-hour increase in time to recanalization decreased the odds of 90-day mRS 0-2 by 2.2%. Conclusion: Among patients with similar 24-hour infarct volume post thrombectomy (≤10 ml), shorter time to successful recanalization is associated with significantly higher rates of early clinical improvement and mRS 0-2 at 90 days. Increased penumbral ischemic time may have an impact on outcomes post stroke thrombectomy.

Abstract P830: Using a Nurse Tasklist in an Electronic Medical Record to Achieve Compliance With Documentation of Post Procedure Assessments

Background: For stroke centers performing endovascular procedures, ensuring documentation of post procedure assessments - site and pulse - is not only important for patient safety but also for program certification. Not being able to demonstrate the appropriate documentation during certification site visits can lead to survey findings and action plans that must be created and managed. Use of tools in an EMR can assist the nurse with documentation compliance for these important assessments. Methods: The electronic medical record (EMR) build was mirrored after an already established process for post IV thrombolytic monitoring. When the thrombolytic order set is initiated and the IV thrombolytic medication is documented on the medication administration record, tasks “fire” to the nurse tasklist related to post thrombolytic monitoring for the 24 hour post IV monitoring period. The nurse can select the task on the tasklist and it takes the nurse to the appropriate place to document as well as at the appropriate time to document. Use of this process helped to drive compliance with post IV thrombolytic monitoring documentation. In order to achieve compliance for post procedure assessments documentation, this same process was requested by nursing. To achieve this, the EMR was designed to “fire” tasks to the nurse tasklist when the post thrombectomy order set is initiated and the time hemostasis is achieved is documented; these tasks cover the post thrombectomy monitoring for the required 24 hours. Part of these tasks include post procedure assessments. Results: From May 2019 to October 2019 the average monthly compliance for post procedure assessments was 77.6%. In November 2019, the appropriate tasking function was implemented in the EMR and education related to the new process was provided. From December 2019 to May 2020 average monthly compliance has been 91.1% with a monthly compliance rate greater than 90% since February 2020. Conclusions: Use of the nurse tasklist in an electronic medical can assist the nurse with documentation of post procedure assessments and achieve documentation compliance.

Abstract 13484: Acute Coronary Syndrome: A Unique Presentation of Libman Sacks Endocarditis

Introduction: Systemic Lupus Erythematosus (SLE) is a chronic inflammatory disease with multiorgan involvement. Cardiac involvement can range from endocarditis to cardiomyopathy. We present a case of SLE complicated by Libman Sacks Endocarditis (LSE) presenting as an acute coronary syndrome (ACS). Case Presentation: A 34 year old male with a history of SLE, DVT/PE, RCA thrombus status post thrombectomy, noncompliance and drug abuse presented to the hospital with complaints of central chest pain associated with right neck, jaw, mouth and arm pain. Vitals were stable. Troponin increased from 0.8 to 13. EKG demonstrated inferior Q waves and ST elevation. CT angiogram was negative for pulmonary embolism but revealed a mobile aortic mass involving the right coronary cusp at the origin of right coronary artery. Transthoracic echocardiogram confirmed this finding. He was started on an infusion of heparin. Surgical evaluation was obtained for emergent thrombectomy and coronary artery bypass grafting. Due to the aortic root thrombus, coronary angiogram was not performed. Lower extremity venous and arterial doppler revealed chronic bilateral DVTs as well as a thrombus in the right common femoral artery. A right heart catheterization demonstrated normal cardiac output and intracardiac filling pressures.Rheumatology was consulted and the patient’s presentation was deemed secondary to Libman sacks endocarditis in the setting of untreated SLE. The pro-coagulant state was chronic and exacerbated secondary to medical noncompliance. Patient was started on hydroxychloroquine with plans for long term anti-coagulation with warfarin in addition to daily aspirin. His symptoms subsided and was discharged home with plans for outpatient follow up. Discussion: Libman sacks endocarditis is a form of noninfectious endocarditis in SLE patients with deposition of thrombi on heart valves. In literature it has been reported to cause valvular dysfunction and cerebrovascular thromboembolism. Our case was unique as it represents a rare manifestation of LSE with an embolic event to a coronary vessel causing ACS. The patient was known to have had prior LSE and due to the complexity of his case and history of medical noncompliance, he was deemed a poor surgical candidate.

Abstract WP65: Clinical and Radiographic Characterization of Cerebral Hyperdensities on Post-thrombectomy Conventional Non-contrast Ct Brain: Differentiating Between Contrast Staining and Post-thrombectomy Hemorrhage

Background: Post-interventional cerebral hyperdensities (PCHD) are present 31.2 to 87.5% of the time on post-thrombectomy (PT) CT. It can be difficult for radiologists to differentiate if PCHD represents intracerebral hemorrhage (ICH) or contrast staining using conventional CT. The ability to accurately determine the etiology of PCHD may be important for a patient’s outcome. Methods: We retrospectively investigated clinical risk factors, imaging findings, and interventional technique of patients who had a thrombectomy from 2011-2017 (n=238) at a Comprehensive Stroke Center. 112 patients with anterior circulation infarcts and immediate PT CTs as well as either a PT MRI or follow-up CT within 48 hours were included. Two experienced neuroradiologists interpreted all imaging. Baseline demographics and imaging characteristics were collected. The presence of ICH was determined by dephasing on gradient echo or by its persistence &gt; 2 days on repeat CT. Chi-square and Fisher’s exact tests were used for statistical significance, and logistic regression to determine risk estimates. Results: 84% of patients had PCHD, of which 56% had ICH. Patients had similar demographics (ICH: median age 69, 47.5% female; non-ICH: median age 71, 42.5% female). Higher pre-thrombectomy ASPECTS score (OR 0.62, p &lt; 0.05) decreased the risk of ICH, and higher Hounsfield units (HU) of PCHD both on immediate (OR 1.04, p &lt; 0.05) and intermediate (OR 1.1, p &lt; 0.0005) PT CT increased the risk of ICH. PCHDs in the deep grey matter (OR 2.84, p &lt; 0.05) and demonstrating a confluent pattern (OR 3.9 p &lt; 0.05) increased the likelihood of ICH. 10% increase risk of ICH was seen for every HU increase in density on PT CT at 24 or 48 hours. A 50% decrease in ICH was observed for each unit increase of the pre-thrombectomy ASPECTS score. ROC revealed the optimal cut-off for predicted probability as 0.64, sensitivity 70.2% and specificity 69.2%. The AUC for the predicted model was 0.84 (95%CI= (0.75- 0.92, p &lt;0.0001). Conclusion: Several imaging characteristics of PCHDs and ASPECTS score can help differentiate between the PT ICH and contrast staining. Application of these variables to patients in the immediate PT period may change clinical management.

Safety and Efficacy of Intra-arterial Tirofiban Injection During Mechanical Thrombectomy for Large Artery Occlusion.

The safety and effect of intra-arterial (IA) tirofiban, a glycoprotein IIb/IIIa inhibitor, during the stent retriever mechanical thrombectomy (MT) was investigated. From January 2015 to May 2019, a total of 327 patients underwent mechanical thrombectomy of large artery occlusions (LAO). Patients were classified into two groups: MT with IA tirofiban (MTT) group and MT only (MTO, without IA tirofiban) group. Clinical outcomes, radiological results, and various complications, such as post thrombectomy hemorrhage, symptomatic hemorrhage, other systemic bleeding, and hemorrhagic transformation of infarct were evaluated by comparing the MTT group and MTO group. In addition, subgroup analysis was performed for patients who underwent MT with prior intravenous (IV) tissue plasminogen activator (t-PA). The MTT group needed a lower mean number of stent passes and showed a re-occlusion rate as compared with the MTO group (P=0.038 and 0.022, respectively). Between the two groups, there were no statistically significant differences in post thrombectomy hemorrhage, symptomatic hemorrhage, other systemic bleeding complications, or hemorrhagic transformation of infarct (P = 0.511, 0.397, 0.429, and 0.355, respectively). In the subgroup analysis, similar findings were observed. The use of IA tirofiban during MT seems to be safe and potentially more effective than only MT without IA tirofiban, even in patients who used IV t-PA before MT.

Value of Brain Computed Tomographic Angiography to Predict Post Thrombectomy Final Infarct Size and Clinical Outcome in Acute Ischemic Stroke.

Aims:This study aims to analyze the predictor in preoperative brain computed tomographic angiography (CTA) for final infarct and outcome in postendovascular thrombectomy patient.Subjects and Methods:52 patients were retrospectively reviewed. The Alberta Stroke Program Early Computed Tomography Score (ASPECTS) comparison between preoperative noncontrast computed tomography (NCCT) and 24-h NCCT as well as preoperative CTA source image (CTA-SI) and 24-h NCCT were performed. Factors associated with increased ASPECTS and clinical outcome were evaluated.Results:Preoperative NCCT ASPECTS = 24-h NCCT in 23%. Whereas, 46% showed preoperative CTA-SI ASPECTS = 24-h NCCT. Moreover, 40.4% showed 24-h NCCT ASPECTS > preoperative CTA-SI (increased ASPECTS). The two significant factors associated with increased ASPECTS are thrombolysis in cerebral infarct score 2b/3 (P = 0.02) and good collateral status (P = 0.02). Finally, good clinical outcome was associated with age <60 (P = 0.04), preoperative CTA-SI ASPECTS >5 (P = 0.01), good collaterals status (P = 0.02), and increased ASPECTS (P = 0.05).Conclusions:Preoperative brain CTA provided the necessary factors that are associated with good clinical outcomes, which are CTA-SI ASPECTS > 5, good collateral status, and increased ASPECTS.