Multicenter comparison using two AI stroke CT perfusion software packages for determining thrombectomy eligibility

BACKGROUND

Stroke AI platforms assess infarcted core and potentially salvageable tissue (penumbra) to identify patients suitable for mechanical thrombectomy. Few studies have compared outputs of these platforms, and none have been multicenter or considered NIHSS or scanner/protocol differences. Our objective was to compare volume estimates and thrombectomy eligibility from two widely used CT perfusion (CTP) packages, Viz.ai and RAPID.AI, in a large multicenter cohort.

METHODS

We analyzed CTP data of acute stroke patients with large vessel occlusion (LVO) from four institutions. Core and penumbra volumes were estimated by each software and DEFUSE-3 thrombectomy eligibility assessed. Results between software packages were compared and categorized by NIHSS score, scanner manufacturer/model, and institution.

RESULTS

Primary analysis of 362 cases found statistically significant differences in both software's volume estimations, with subgroup analysis showing these differences were driven by results from a single scanner model, the Canon Aquilion One. Viz.ai provided larger estimates with mean differences of 8cc and 18cc for core and penumbra, respectively (p<0.001). NIHSS subgroup analysis also showed systematically larger Viz.ai volumes (p<0.001). Despite volume differences, a significant difference in thrombectomy eligibility was not found. Additional subgroup analysis showed significant differences in penumbra volume for the Phillips Ingenuity scanner, and thrombectomy eligibility for the Canon Aquilion One scanner at one center (7 % increased eligibility with Viz.ai, p=0.03).

CONCLUSIONS

Despite systematic differences in core and penumbra volume estimates between Viz.ai and RAPID.AI, DEFUSE-3 eligibility was not statistically different in primary or NIHSS subgroup analysis. A DEFUSE-3 eligibility difference, however, was seen on one scanner at one institution, suggesting scanner model and local CTP protocols can influence performance and cause discrepancies in thrombectomy eligibility. We thus recommend centers discuss optimal scanning protocols with software vendors and scanner manufacturers to maximize CTP accuracy.

Abstract WP45: VISIION-S: Viz.ai Implementation Of Stroke Augmented Intelligence And Communications Platform To Improve Indicators And Outcomes For A Comprehensive Stroke Center And Network - Sustainability

Background: As Comprehensive Stroke Centers (CSCs) strive to improve neurointerventional (NIR) times, process improvements have been put in place to streamline workflows. Our prior publication (VISIION) demonstrated an improvement in key performance indicators (KPIs) in our CSC. The purpose of this study is to analyze whether the positive results demonstrated were sustainable.

Methods: Sequential stroke NIR patients being Direct Arriving LVO (DALVO) and telemedicine transfer LVO (BEMI) cases were assessed, including subgroups of DALVO-OnHours, DALVO-OffHours, BEMI-OnHours, and BEMI-OffHours. We analyzed times for the original 6 months pre (6/10/20-1/15/21) and compared them to a 17 months post-implementation (1/16/21- 6/25/22) to evaluate for sustainability. Mann-Whitney U was utilized.

Results: 150 NIR cases were analyzed pre (n=47) v. post (n=103) Viz.ai implementation (DALVO-OnHours 7 v. 20, DALVO-OffHours 10 v. 25, BEMI-OnHours 13 v. 20, BEMI-OffHours 17 v. 38). For Door-to-groin (DTG) assessments, improvement was noted for DALVO-OffHours 39% (157min,96min;p<0.001), DALVO-ALL 25% (127min,95min;p=0.006), BEMI-OffHours 46% (45min,25min;p=0.023), and BEMI-ALL 40% (42min,25min;p=0.005). Activation-to-groin (ATG), door-to-device (DTD), and door-to-recanalization (DTR) showed similar improvements. For DALVO-OffHours, there were significant reductions in door to CT (DTC) 81% (26min,5min;p<0.001), ATG 32% (90min,61min;p=0.036), DTG 39% (157min,96min;p<0.001), DTD 31% (178min,123min;p=0.002), and DTR 32% (197min,135min;p=0.003).

Conclusions: Consistent with our initial 6 month post-implementation pilot, we noted sustainability over a 17 month period with sustained reduction in KPIs for numerous key NIR subgroups. In the greatest opportunity subgroup (DALVO-OffHours), requiring team mobilization off hours without benefit of telemedicine transfer lead time, we noted a significant reduction in all 5 time metrics. Our sustainability finding is important to show that process improvements continued even after the immediate period, making a Hawthorne effect less likely and adding credibility to the results. Models such as this, could be useful for other centers striving to optimize workflow and improve NIR times.

Abstract WP151: DISPARI-TICI: Determining If Stroke Patients Assessed For Revascularization Show Ethnic Disparities In TICI Scores Or Complications

Introduction: There is limited data on ethnic disparities in endovascular therapy (EVT) Thrombolysis In Cerebral Infarction (TICI) revascularization scores and EVT complications. The goal of this study was to compare disparities in TICI scores and complications in Hispanic versus Non-Hispanic ethnicities.

Methods: We retrospectively examined prospectively collected data from an IRB-approved stroke registry at two academic Comprehensive Stroke Centers (CSC). We included acute ischemic stroke (AIS) patients with large vessel occlusion within 24 hours of last known well that underwent EVT between 1/1/2013-6/30/2022. Favorable outcome was defined as TICI 2b-3. Complications of symptomatic intracranial hemorrhage (sICH), life-threatening or serious systemic hemorrhage, or other serious complication were collected within 36 hours of EVT and compared between Hispanic or Non-Hispanic subjects. Data was analyzed using Chi-squared and was adjusted for baseline NIHSS, blood glucose, and age. A p-value of <0.05 was significant.

Results: A total of 411 patients who met study criteria were identified. In Hispanics versus Non-Hispanics, the mean age was 69 vs 70 years, 44.6% vs 48.3% patients were female, and median initial NIHSS was 17 vs 16. The rate of Hispanics in this sample was 29.4% (n=121). There were no differences in baseline characteristics or in patients receiving IV rt-PA prior to EVT between Hispanic and Non-Hispanics (72.6% vs 65.5%; p=0.17). The overall rate of favorable TICI outcome was 93.7% (n=385/411). There was no difference in favorable TICI scores in Hispanic versus Non-Hispanics (96.7% vs 92.4%; p=0.12). Complication rates were also not significantly different in Hispanics versus Non-Hispanics for: sICH (5.8% vs 2.4%; p=0.09), other serious complications (1.7% vs 2.1%; p=0.78), and life-threatening systemic hemorrhage (0.8% vs 0.7%; p=0.88).

Conclusion: There were no differences in TICI outcome or complication rates in Hispanic versus Non-Hispanic patients in these 2 academic CSCs. The use of consistent protocols and pathways at a CSC likely contribute to consistent EVT treatment between ethnicities. Further studies must examine EVT outcomes within various ethnicities and races in multiple stroke centers around the country.

Abstract TP144: VARIANCE-S: Variability Of Assessed Bp Readings In Acute Neuro-intervention Cases And Its Effect On Outcomes Pertaining To Sex Differences

Introduction: Sex differences exist in thrombolytic stroke treatment and outcome and likely in endovascular thrombectomy (EVT). Previous analysis has shown a significant correlation of blood pressure variability (BPV) and sex. The purpose of this study was to assess sex differences in a sample of patients with good recanalization post-with EVT and examine the impact of BPV.

Methods: We conducted a retrospective analysis of prospectively collected data from an IRB approved Stroke Registry of two academic Comprehensive Stroke Centers in Southern California between 2017 and 2022. Patients were included if they had 1) anterior circulation ischemic stroke due to large vessel occlusions (LVO) and 2) underwent successful EVT defined as a TICI 2b or 3 result. Male and female subjects were compared for age, sex, Hispanic ethnicity, initial NIHSS, history of HTN, current antihypertensive use, symptom onset to groin puncture time, door to groin puncture time, and symptomatic ICH (sICH), BPV, onset to groin, and door to groin . Good outcome was defined as mRS 0-2. Chi squared a t-test were used as appropriate.

Results: We included 131 females and 124 males. There was a significant difference between males and females in: 1) history of a fib (76% v 64%, p=0.42); 2) atrial fibrillation during admission (36% v 50%, p=0.01); 3) age (male 67 v female 73 years, p<0.001); 4) post-EVT SBP (137mmHg v 144mmHg, p-0.02). There was a significant difference in onset to groin (p=0.41), but no significant difference in door to groin (p=0.59). When adjusting for time of onset, there was no significant difference in thrombolysis prior to EVT between groups. There was no significant difference in sICH (6 male v 4% female, p=0.50), 90 day mRS (p=0.81); or discharge disposition (p=0.56). BPV was significantly correlated with sex but not significant for any interaction effect with the variables assessed.

Conclusion: This study found no significant sex differences in outcome in this sample. The systems of care provided by an academic, CSC ensure that all patients’ care is expedited and provides the best opportunity for a good outcome in both sexes. Studies of sex differences in EVT treatment and outcome in multiple stroke care settings are vital to reduce disparities in care.

Abstract WP89: Listen: Language Impact On Stroke Time To Evaluation And Intervention

Introduction: Previous reports raised concerns that time dependent treatments in acute ischemic stroke (AIS) might be delayed on non-English speaking patients. Here we report an analysis of patients after AIS stratified by primary language who were admitted to two large comprehensive stroke centers in California. The purpose of this analysis was to examine the impact of primary language on treatment times, frequency and causes of not using thrombolysis.

Methods: We included all patients admitted between 12/2019-4/2022 who presented to a Comprehensive Stroke Center (CSC) using the electronic medical record (EMR). Language preference was identified as English (ES) or Non-English (NES). We compared comorbidities, demographics, baseline NIHSS, stroke time metrics [stroke onset to arrival (LTD), arrival to CT (DTC), arrival to tPA (DTN)], frequency of tPA administration and exclusion for last known normal (LKN) > 4.5 hours between ES and NES. We utilized Chi-squared, t-test, ANOVA as appropriate and a p value of <0.05 was significant.

Results: We identified 1815 patients, ES n=1489, NES n=326. There was no significant difference in the mean age between groups (ES 67±16; NES 66±16, p=0.93). There was no significant difference in mean LTD between groups (NES 99.3±58.9 minutes (min); ES 83.6±52 min). There was no significant difference in mean DTC between groups (NES 13.2±8.5 min; ES 12±10.2 min). There was no significant difference in mean DTN between groups (NES 54.4±23.3 min; ES 53.8±27.9 min). There was a significant difference in ambulance arrival (p=0.001), HTN (p=0.01), DM (p=0.001), drug/alcohol use (p=.001), and smoking (p=.001). There was no significant difference in LKW to door (p=.12), DTC (p=.44), DTN (p=0.88).

Conclusion: Primary language did not affect acute stroke time metrics at this academic CSC. This is likely due to the 24/7 availability of interpreter services at this CSC. Further studies must assess the impact of language preference on stroke time metrics and outcome in a heterogenous sample of healthcare settings. Communicating in patients’ preferred language is vital to rapid care and patient engagement in the acute stroke setting.

Abstract WP109: CHASM: Comparing Hyperacute Advanced Imaging To Guide Interventional Stroke Management

Introduction: “Stroke AI” platforms discriminate potentially salvageable tissue from infarcted core, to determine embolectomy eligibility. Numerous platforms are in clinical use, but studies comparing their results are limited. Our institution has access to both viz.AI and RAPID for CT perfusion analysis; as such, we assessed whether core and penumbra estimates were statistically different between the two software.

Methods: We performed a retrospective review of images from 2/18-1/21 of acute stroke patients with symptoms 6-24 hours from onset who had CTP in the setting of large vessel occlusion (IRB#804221). Studies initially processed through RAPID were re-analyzed by Viz.ai; core volume (CBF<30%), penumbra+core (TMax>6s), and mismatch ratio were compared using paired t-test, and for infinite mismatch McNemar statistics.

Results: A total of 157 cases were identified. 48 were excluded for processing failure or deleted raw data, and 6 research participants were excluded. Viz.ai had larger TMax>6s volumes relative to RAPID (160.13ml,108ml;p=<0.001), but less infinite mismatch (30.1%,40.8%;p=0.04). No significant difference was found for: core volume (16.7ml,18ml;p=0.47), percentage of infarcts >70ml (6.8%,7.8%;p=1.0), and NIR eligibility based on DEFUSE-3 (71.8%,68.9%;p=0.63), with <70ml core(93.1%,92.2%;p=1.0), ≥15ml penumbra (78.6%,76.7%;p=0.79), and mismatch >1.8 (83.1%,81.9%;p=1.0).

Conclusions: Both Viz.AI and RAPID provided similar core volumes and NIR eligibility, which gives assurance that both algorithms provide similar actionable results. Reasons why Viz.ai showed larger TMax>6s volumes but less infinite mismatch are unclear, though the latter implies that viz.ai identifies a potential core that may or may not be there in more cases. Penumbra estimation is multifactorial and variance may be due to algorithm alterations in voxel selection to account for artifact, scanner and AI protocols as both have different standards for contrast, radiation exposure, and slice #. Understanding if Viz.ai overestimates or RAPID underestimates TMax>6s will require further assessments of imaging and functional outcome variables. Further analysis to assess if results are accounted for by the above factors is ongoing.

Viz.ai Implementation of Stroke Augmented Intelligence and Communications Platform to Improve Indicators and Outcomes for a Comprehensive Stroke Center and Network

BACKGROUND AND PURPOSE

Comprehensive stroke centers continually strive to narrow neurointerventional time metrics. Although process improvements have been put in place to streamline workflows, complex pathways, disparate imaging locations, and fragmented communications all highlight the need for continued improvement.

MATERIALS AND METHODS

This Quality Improvement Initiative (VISIION) was implemented to assess our transition to the Viz.ai platform for immediate image review and centralized communication and their effect on key performance indicators in our comprehensive stroke center. We compared periods before and following deployment. Sequential patients having undergone stroke thrombectomy were included. Both direct arriving large-vessel occlusion and Brain Emergency Management Initiative telemedicine transfer large-vessel occlusion cases were assessed as were subgroups of OnHours and OffHours. Text messaging thread counts were compared between time periods to assess communications. Mann-Whitney U and Student t tests were used.

RESULTS

Eighty-two neurointerventional cases were analyzed pre vs. post time periods: (DALVO-OnHours 7 versus 7, DALVO-OffHours 10 versus 5, BEMI-OnHours 13 versus 6, BEMI-OffHours 17 versus 17). DALVO-OffHours had a 39% door-to-groin reduction (157 versus 95 minutes, P = .009). DALVO-All showed a 32% reduction (127 versus 86 minutes, P = .006). BEMI-All improved 33% (42 versus 28 minutes, P = .036). Text messaging thread counts improved 30% (39 versus 27, P = .04).

CONCLUSIONS

There was an immediate improvement following Viz.ai implementation for both direct arriving and telemedicine transfer thrombectomy cases. In the greatest opportunity subset (direct arriving large-vessel occlusion-OffHours: direct arriving cases requiring team mobilization off-hours), we noted a 39% improvement. With Viz.ai, we noted that immediate access to images and streamlined communications improved door-to-groin time metrics for thrombectomy. These results have implications for future care processes and can be a model for centers striving to optimize workflow and improve thrombectomy timeliness.

Abstract WP120: Can Early Transcranial Doppler Ultrasound Predict Early Neurological Deterioration And Risk Of Hemorrhagic Transformation After Endovascular Treatment?

Background: Recent advances in endovascular therapy (EVT) have led to a significant improvement in functional outcomes of patients with stroke. However, early neurological deterioration (END) after EVT has still remained a concerning issue. Reasons for END include reocclusion, hyperperfusion after recanalization, and hemorrhagic transformation. The current study was designed to assess the feasibility of early transcranial Doppler (TCD) after EVT, to identify association between TCD findings and END.

Methods: This is a pilot study to assess the feasibility of TCD prior and early (within 60 minutes) after EVT. For all selected arteries, we measured peak systolic velocity, end diastolic velocity, mean flow velocity and pulsatility index. Patients were followed for three months after the intervention and disability was measured using modified Rankin scale (mRS). We examined the possible association between active leptomeningeal collateral flow after EVT and END.

Results: Between October 16, 2020, and March 28, 2021, we recruited 20 acute ischemic stroke patients with large vessel occlusion who underwent EVT. Five patients were excluded because of a poor temporal window; two had an unsuccessful intervention. Four patients had END and all of them had active leptomeningeal flow with elevated blood pressure after EVT. In cases without END, we did not observe any flow diversion or active leptomeningeal collateral after EVT.In those without significant post-stroke disability (mRS<2), we did not observe any active leptomeningeal flow or flow diversion with blood pressure of ≤ 155/85. Most patients with post-stroke disability (mRS ≥ 2) had either flow diversion or active leptomeningeal flow in the presence of blood pressure ≥ 170/93. Hyperemia was associated with hemorrhagic transformation, particularly in the presence of elevated blood pressure. All cases with symptomatic hemorrhagic transformation had hyperemia.

Conclusion: TCD is a feasible approach early after EVT. It has clinical implications in identifying those with END and risk for sICH. Early TCD after EVT may provide personalized BP management based on individualized cerebral flow and the presence of active collateral flow after EVT. Studies with larger sample size are warranted.

Abstract TP125: Interpreter Requirements Needed For Tpa Evaluations And Resulting Performance (INTERP)

Introduction: Acute ischemic stroke (AIS) patients requiring interpreter services during an acute stroke code can experience care delays. Prior research has shown no differences in door-to-needle times in non-English fluent patients. The purpose of this study was to examine the influence of interpreter service needs (IS) on time metrics of tPA administration.

Methods: We retrospectively reviewed prospectively collected data from our Comprehensive Stroke Center database (1/2011-4/1/2021) and EMR. Subjects with a discharge diagnosis of AIS for whom a “stroke code” was activated were included; in-house strokes were excluded. Baseline characteristics, frequency of tPA, tPA exclusions, NIHSS, and tPA time metrics were compared between patients who did or did not require IS. Analyses utilized ANOVA, t Test, or Pearson’s Chi-squared test as appropriate.

Results: Of 1,043 patients with AIS, 41 had a documented need for IS. tPA was administered in 9 IS and 322 non-IS patients. In IS patients, there were no differences in baseline characteristics between those who received tPA and those who did not. In patients who received tPA, there was a larger amount of Hispanic ethnicity (p<0.01) and hyperlipidemia (p=0.02) in patients requiring IS. There were no tPA rate differences between those that did not and did require IS (22% vs 32%; p=0.22). Patients excluded from tPA due to being out of the window were more likely to have required IS (35% vs 59%; p = 0.003). Onset to arrival (p = 0.89), arrival to treatment decision (p = 0.85), door to needle (p=0.41), and onset to treatment (0.41) were not different in IS patients. Median NIHSS was not different overall (p=0.70) or in tPA patients (p=0.36).

Conclusions: This study found no significant difference in frequency or time metrics of tPA administration in AIS patients requiring interpreter services during an acute stroke code. If a patient required an interpreter, they were more likely to be excluded from tPA on the basis of time. We hypothesize this is due to increased time required to obtain relevant history or exam data or small sample size. Further work is planned in larger data sets to ensure resource availability to patients who are in need of interpreter services.

Abstract TP22: Coagulation Markers And Stroke Severity In Covid-19 Associated Acute Ischemic Stroke

Background: COVID-19 is thought to induce a pro-thrombotic state, which might increase stroke risk. The purpose of this project is to assess stroke severity, type and coagulation markers such as D-dimer, fibrinogen, and CRP in patients with acute ischemic stroke (AIS) and COVID-19, compared to a control group of AIS without COVID-19.

Methods: We captured discharge diagnosis of all patients at our medical center with AIS and COVID based on their discharge ICD-10 coding between June 2020 and May 2021; and identified AIS without COVID matched for age, sex, race, and ethnicity. Group 1 was AIS with COVID-19, Group 2 matched (3:1) AIS without COVID-19. We compared baseline demographics, NIHSS, D-dimer, fibrinogen, CRP, presence of large vessel occlusion (LVO) in COVID-19 AIS vs non-COVID-19 AIS. We used a T test to compare parametric and Mann Whitney U for non-parametric values.

Results: In total 23 (of 397 total AIS) patients were in Group 1; 69 in Group 2. D-dimer levels (mean) were 3237.3 in Group 1, and 2706.8 in Group 2 (NS), Fibrinogen 464.4 and 379.8 (NS), CRP 7.9 and 9.4 (NS). Median NIHSS was 21 versus 5 (p=0.003). LVO was present in 17 patients in Group 1 (73%) and 23 (33%) in Group 2 (NS). In total, only 5.8% (23 of 397) of all AIS in our data had Covid-19 infection.

Conclusion: COVID in stroke was an infrequent finding in our sample (5.8%). Patients with COVID and stroke had higher initial stroke severity, but did not differ in coagulation values. Weather coagulation markers can help distinguish patients with COVID related stroke will require subsequent studies. We need additional data before treatment recommendations specific to stroke in COVID can be made.

Abstract WP84: (VISIION): Viz.ai Implementation Of Stroke Augmented Intelligence And Communications Platform To Improve Indicators And Outcomes For A Comprehensive Stroke Center And Network

Background: Comprehensive Stroke Centers (CSCs) strive to narrow rt-PA and “Door To Groin” (DTG) neurointerventional (NIR) times. Process improvement workflows have been put in place for rt-PA. While similar processes have been implemented to streamline workflows for hyperacute NIR cases, complex pathways, disparate imaging locations, and fragmented communications all highlight a need for continued improvements.

Methods: This quality improvement initiative (IRB #210525) was implemented to assess our transition to the Viz.ai platform for immediate image review and centralized communication and its effect on key performance indicators (KPIs) in an already robust CSC. We compared 6 month periods prior to and following deployment. Sequential stroke NIR patients were included. Both Direct Arriving LVO (DALVO) and telemedicine transfer LVO (BEMI) cases were assessed. We assessed subgroups of DALVO-OnHours, DALVO-OffHours, BEMI-OnHours, and BEMI-OffHours. Mann-Whitney U was utilized.

Results: Eighty-two NIR cases were analyzed pre v. post Viz.ai implementation (DALVO-OnHours 7 v. 7, DALVO-OffHours 10 v. 5, BEMI-OnHours 13 v. 6, BEMI-OffHours 17 v. 17). DALVO-OnHours improved 19% (97min, 79min; p=0.201) in median DTG times. DALVO-OffHours had a significant 39% reduction (157min, 95min; p=0.009). DALVO-“All” showed a significant 32% reduction (127min, 86 min; p=0.006). BEMI-OnHours improved 18% (37min, 31min; p=0.337). BEMI-OffHours improved 38% (45min, 28min; p=0.077). BEMI-“All” significantly improved 33% (42min, 28min; p=0.036). Overall, there was a 22% reduction (50min, 39min; p=0.066) after Viz.ai implementation.

Conclusions: There was an immediate KPI improvement following Viz.ai implementation for both direct arrival and telemedicine transfer NIR cases (32% and 33% respectively). In the greatest opportunity subset (direct arriving cases requiring team mobilization off hours without benefit of telemedicine transfer lead time) we noted a 39% improvement. With Viz.ai, we noted immediate access to images and streamlined group communications, even in an already well-functioning CSC. These results have implications for future care processes and can be a model for centers striving to optimize workflow and improve NIR timeliness.

Abstract TP121: Examination Of Initial NIHSS And Discharge Disposition In Patients Hospitalized With Acute Ischemic Stroke

Introduction: Acute ischemic stroke (AIS) patients require post-acute care (PAC) rehabilitation that is consistent with degree of stroke deficit. Appropriate PAC disposition for AIS patients varies widely. We examine the relationship between initial National Institutes of Health Stroke Scale (NIHSS) and discharge disposition to determine if stroke severity is associated with disposition.

Methods: In our IRB-approved database, consecutive Emergency Department stroke code activations with confirmed diagnosis of AIS were retrospectively analyzed from January 2004-May 2021 at UC San Diego. Patients were grouped into mild (NIHSS 0-5), moderate (NIHSS 6-14), and severe (NIHSS >14) stroke. Outcome variables were PAC disposition: Home, Inpatient Rehab Facility (IRF), Skilled Nursing Facility (SNF), Expired, and Other. Chi-squared and Kruskal-Wallis followed by pairwise proportion tests were used for analysis. Analyses were adjusted for age, sex, baseline modified Rankin score (mRS), and acute stroke treatment.

Results: Total 2316 patients were included for analysis. There was a difference between initial stroke severity and discharge disposition overall (p<0.001). (Table 1). Mild stroke patients had less discharges to IRF, SNF, Expired, or Other compared to moderate (p<0.001) and severe (p<0.001) strokes. There was no difference between moderate and severe stroke patients discharged to IRF (p=0.44) or SNF (p=0.48). Age, baseline mRS, and receiving acute stroke treatment were independent predictors for discharge to home, IRF, and SNF. Baseline mRS was an independent predictor for Expired patients.

Conclusion: Patients with mild strokes are discharged home more than moderate and severe strokes, but there was no difference between moderate and severe stroke patients discharged to either IRF or SNF. This suggests PAC disposition is not consistent with stroke severity and further studies are needed to investigate other factors related to final disposition.

Abstract P724: Perimenopausal Women With Migraine Present With Stroke at a Younger Age and With Less Comorbid Diabetes

Introduction: Migraine is an independent risk factor for ischemic stroke. Frequency and severity increases in the perimenopausal period accompanied by marked vasomotor symptoms (VMS) such as hot flashes, flushing and night sweats. There is emerging evidence that VMS increases the risk of vascular disease including stroke. The purpose of this study was describe the demographics and co-morbidities of perimenopausal females with and without migraine that experience acute ischemic stroke (AIS).

Methods: In this IRB approved study, electronic health record (EHR) data was obtained from a large, academic, comprehensive stroke center from 1/1/2015 to 1/1/2020. Inclusion criteria included female sex, age 42-65 years, and hospital diagnosis code of AIS. Hemorrhagic stroke, TIA, vasculopathy, and endocarditis associated strokes were excluded. Perimenopause was defined as age ≥42 and ≤65 years. Hormonal and menopausal status was not available in the EHR. We compared the baseline demographics and co-morbidities by ICD10 codes of subjects with and without migraine. Chi squared was used to compare categorical data and t test for continuous. Spearman rho was used to assess correlations.

Results: We identified 660 subjects who met study criteria (n=83 with migraine; n=577 without migraine). Migraine positive subjects were significantly younger (mean age 58 vs 66 years, p=0.03) at time of AIS. Migraine positive subjects identified significantly more often as White (47%) compared to Black (10%), Asian (7%), Pacific Islander (1%), Native American/Alaskan (1%), Other/Mixed Race (31%), and unknown (3%), p=0.001. There was no significant difference in Hispanic ethnicity (p=0.87), hypertension (p=0.66), hyperlipidemia (p=0.12), or atrial fibrillation (p=0.84). Comorbid diabetes was significantly higher in the non-migraine group (94% vs 6%, p<0.001).

Conclusion: Perimenopausal women with concomitant history of migraine present with AIS at younger ages and with lower rates of diabetes than those without a migraine history. Future research must be done to assess the correlation of menopausal symptom severity, hormone levels at time of AIS, and stroke characteristics to further understand the role of menopause in stroke risk.

Abstract P645: Sex Differences in the Platelet Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) Trial

Introduction: Sex differences have been noted in stroke and estrogen is associated with decreased platelet aggregation. The purpose of this study was to assess sex differences in the Platelet Oriented Inhibition in New TIA and Minor Ischemic Stroke (POINT) study.

Methods: We performed a secondary analysis of the POINT study. Patients were analyzed by intention to treat group: 1) Males, standard (n=1351) aspirin; 2) Males, intervention (n=1335) clopidogrel+aspirin; 3) Females; standard (n=1098) aspirin; and 4) Females, intervention (n=1097) clopidogrel+aspirin. Groups were compared for baseline demographics via ANOVA followed by Mann Whitney U. A Cox Proportional Hazards Model was used to assess the primary safety and efficacy outcomes.

Results: Baseline characteristics were significantly different only for race (p<.001) with white race being most represented. The primary outcome occurred in 6.4% of standard males, 6.7% of standard females, 5.1% of intervention males, and 4.8% of intervention females (p=0.12). Cox models suggest that male intervention participants had lower hazard rate compared to male standard participants (HR=0.79, CI:0.58-1.09) and female intervention participants had a lower hazard compared to male standard (HR=0.76, CI: 0.54-1.07) but this was not statistically significant. Major hemorrhage occurred in 0.4% of standard males, 0.5% of standard females, 0.8% of intervention males, and 1.1% of intervention females (p=0.11). Female intervention subjects had a significantly higher hazard rate of major hemorrhage compared to standard males (HR=2.99, CI:1.06-8.52) with no other between group differences.

Conclusion: This study found that there were no significant sex differences in the reduction of recurrent vascular events in the POINT trial. The rate of major hemorrhage was higher in female intervention compared to male standard subjects, but there was no difference in rates between the female groups or the male intervention group. Future studies must provide a sample size with enough power to assess for sex differences to optimize care. Both males and females benefit from combination therapy but the risk of major hemorrhage must be considered.

Abstract P307: The ALPHA Sign in the Diagnosis of Potential Stroke

Background: Any clinical feature that may improve the early recognition of, or increase pretest probability of, acute stroke could shorten treatment times. We evaluated the sensitivity and specificity of the "Arm and Leg Positioning and self-Help Assessment” (ALPHA) sign in a predominantly stroke population. This sign was developed from the observation that some stroke patients guard the affected limb. Even mild deficits seem to have minimally supportive micro-gestures of one hand touching or lightly supporting the affected limb.

Methods: IRB approval was obtained to review available videos of 63 stroke and non-stroke patients. Observers were instructed to only watch the initial 30 seconds of each video and focus on the limbs. The remaining video, and all the audio, were withheld. Videos were independently scored for the ALPHA sign. A composite score, defined as positive if &gt;/= 50% of examiners reported its presence, was assigned. Scores were compared to true diagnosis (stroke/ CNS lesion was positive if there was a scorable deficit and imaging positive CNS lesion). Sensitivity analyses were performed.

Results: Of the original 69 videos, 37 were from the outpatient setting (21 with stroke or other CNS lesions; 16 neurologically intact) and 26 were from the inpatient setting (20 with stroke or other CNS lesions; 6 neurologically intact). The ALPHA sign had a specificity of 86.4% and positive predictive value of 89.7%. Sensitivity was 63.4% and negative predictive value was 55.9%.

Conclusions: High specificity and positive predictive value of the ALPHA sign were found suggesting that the recognition of subtle supportive gestures may help in early identification of CNS lesions during a stroke code. As expected, the sign had a lower sensitivity as the cohort was not limited to motor-only deficits. Further assessments in other stroke types, assessing a larger cohort and more examiners of various training level, are planned.

Abstract P276: The Perception/ Misperception of Treatability of 7AM vs 7PM Stroke Codes

Background: Prior studies have assessed the effect of time of day and day of week on stroke code frequency. Observations that early evening times might result in more treatable stroke cases have been noted. Experiential data raise the question as to whether 7pm codes are often “real” and “intervenable”. Understanding treatment patterns can help allocate resources. We assessed whether 7am early morning stroke code activation resulted in higher yield of acute treatment compared to 7pm evening stroke codes.

Methods: A retrospective analysis of prospectively collected data from an IRB approved stroke registry, from 7/2004-7/2020, was performed. All patients presenting as a stroke code to our comprehensive stroke center (CSC) or covered hospitals were included. Subjects were divided into 2 groups: (7ASC): Stroke code called 06:00-08:00 and (7PSC) Stroke code called 18:00-20:00. Treatment was defined as receiving any thrombolytic or endovascular intervention. Chi-squared was used for categorical and 2-proportion Z-Test was used for proportional data.

Results: A total of 988 subjects were identified with stroke codes in these time epochs. Total number of code activations (including mimics) was higher in 7PSC group [277(28.0%) 7ASC, 711(72.0%) 7PSC; p<0.0001] compared to 7ASC group. For patient with final diagnosis of stroke, number of code activations remained higher in 7PSC group [134(28.3%) 7ASC, 340(71.7%) 7PSC; p<0.0001]. Acute treatment rates did not differ between groups [22.7% 7ASC, 22.5% 7PSC; p=0.62].

Conclusions: We noted more 7PSC stroke codes even when not adjusting for the extended stroke code time windows in later years of the database. We hypothesize that this may be due to more witnesses being available in the early evening. In spite of this finding, acute treatment rates did not differ between times. This data does not support provider perception that early morning codes are unlikely to be “true or treatable” and early evening codes are often “true and treatable”. Irrespective of perception, stroke providers in a CSC must be immediately and equally available in both early morning and evening. This also has ramifications for interventional procedure staffing and clinical trial enrollments. Further analyses in a larger dataset are warranted.

Abstract P697: Vasomotor Symptoms of Menopause Increase Stroke Risk in Migraineurs

Introduction: The relationship between migraine and stroke, especially in migraine with aura, has been well-established. There is emerging evidence that vasomotor symptoms (VMS) such as hot flashes, flushing and night sweats associated with menopause increases the risk of vascular events, especially in the perimenopausal period. The aim of this study was to compare vascular risk factors in perimenopausal females with and without migraine with concomitant acute ischemic stroke (AIS).

Methods: In this IRB approved study, we examined patient level data using the SlicerDicer function within Epic at a large, academic, comprehensive stroke center from 1/1/2015 to 1/1/2020. Inclusion criteria included female sex, age 42-65 years, and hospital diagnosis code of AIS. Hemorrhagic stroke, TIA, vasculopathy, and endocarditis associated strokes were excluded. Perimenopausal was defined as age ≥42 and ≤65 years. Hormonal and menopausal status was not available. We compared rates of co-morbidities by ICD10 codes of subjects with and without migraine using descriptive statistics and Chi squared analysis.

Results: We identified 2296 (90%) women without migraine (Group 1) and 243 (10%) with migraine (Group 2) admitted for AIS. The five most common risk factors for AIS in group 1 were hypertension (56%), hyperlipidemia (37%), diabetes (30%), obesity (23%) and atrial fibrillation (11%). VMS was coded in 8% and tobacco use 7%. In group 2 we found hypertension (50%), hyperlipidemia (42%), migraine with aura (31%), obesity (23%), diabetes (20%). VMS was coded in 14%, atrial fibrillation in 12%, and tobacco use in 6%. Group 2 patients were more likely to have VMS (p = 0.008) and less likely to have diabetes (p=0.001). There were no other significant differences identified.

Conclusions: Vasomotor symptoms in menopause are a significant risk factor for AIS in perimenopausal women with migraine. VMS should be assessed for clinically and included as a risk factor for stroke, especially in those with additional vascular risk factors. Future studies should include a diverse sample to assess the impact of VMS in a heterogeneous population.

Abstract P689: Do Cyclic Patterns of Stroke Code Activation Occur in a Comprehensive Stroke Center?

Background: The effects of circadian rhythm on stroke can include increases in morning heart rate, blood pressure, catecholamines, platelet aggregation, and hypercoagulability and might correlate with higher numbers of morning strokes. We assessed time of day and frequency of stroke code activation for a potential role of circadian rhythm in stroke risk.

Methods: A retrospective analysis of prospectively collected data from an IRB approved stroke registry, from July 2004 to July 2020, was performed. Codes were included where stroke codes were activated with last known well (LKW) <6 hours to limit the effect of wake-up strokes and equalize changing practice patterns over time. Subjects were divided into four epochs based on code activation: Night (00:00-05:59), Morning (06:00-11:59), Afternoon (12:00-17:59), and Evening (18:00-23:59). Confirmed diagnosis of stroke, baseline blood pressure (SBP & DBP), heart rate (HR), and PTT were compared. Chi squared was used to compare categorical data and t test for continuous.

Results: A total of 5,366 subjects were identified. Stroke code activations differed across epochs (Night n=312, 5.81%; Morning n=1439, 26.82%; Afternoon n=2207, 41.13%; Evening n=1408, 26.24%: p<0.0001). In the subset analysis of true strokes, activations also differed across epochs (Night n=125, 5.26%; Morning n= 831, 34.95%; Afternoon n=934, 39.28%; Evening n=488, 20.52%: p<0.0001). Overall, SBP was different with Evening highest and Morning lowest (x 151.6, x 148.2;p=0.01). Overall DBP showed Night highest and Afternoon lowest (x 83.9, x 81;p=0.002). Heart rate showed Night highest and Morning lowest (x 84.9, x 81.6;p=0.002).

Conclusions: This study found that most stroke code activations occur in Afternoons at this CSC. This may be due to patient level characteristics, bystander availability, or other factors. Future studies should assess multi-center data and include other circadian rhythm biomarkers.

Abstract P532: Does Atrial Fibrillation Impact Rate of Symptomatic Intracranial Hemorrhage in Acute Ischemic Stroke Patients Treated With rt-PA and/or Endovascular Treatment?

Background: Patients with acute ischemic stroke (AIS) due to atrial fibrillation (afib) may have increased complications from intravenous thrombolysis or endovascular treatment (ET) compared to other stroke subtypes. The purpose of this study was to compare the rates of symptomatic intracranial hemorrhage (sICH) in patients with and without a history of a fib treated with IV rt-PA and/or ET.

Methods: Consecutive stroke code activations were retrospectively analyzed from January 2004-June 2020 at an academic comprehensive stroke center. Patients were included if they were treated with IV rt-PA and/or ET within 24 hours of stroke onset. Patients were stratified into the six groups:1-No hx of a fib with ET only, 2-Hx of a fib with ET only, 3-No hx of a fib with IV rt-PA plus ET, 4-Hx of a fib with IV rt-PA plus ET, 5-No hx of a fib with IV rt-PA only, 6-Hx of a fib with IV rt-PA only. Primary outcome was defined as any sICH within 72 hours of treatment using the NINDS definition. Baseline demographics were compared. Chi squared was used to assess differences in sICH rates and logistic regression to compare individual groups. Analyses were both unadjusted and adjusted for baseline NIHSS, age, sex, baseline blood pressure, pre-stroke mRS, smoking status, and baseline glucose.

Results: We identified 720 AIS patients who received acute treatment (IV rt-PA: n=578; ET: n=100; IV rt-PA+ET:n=18). There was a significant difference in sex (p=0.005); Hispanic ethnicity (p=0.002); current smoking (p=<0.001); current alcohol use (p=0.03), CHF (p=0.01); and age (p<0.0001) between groups. Baseline NIHSS was significantly higher in Group 4 (23, SD 8, p=<0.001).In adjusted analysis, there was no significant difference in sICH in patients with a fib after receiving IVtPA (OR 1.53, CI 0.47-4.99, p=0.48), ET (OR 0.93 , CI 0-∞, p=1.00), or both (OR 0.25,CI 0.00-9.07, p=0.45) compared to those without afib. There was no significant difference in sICH in adjusted analyses in patients with and without a fib overall (OR 0.93, CI 0-∞, p=1.00).

Conclusion: In this study, atrial fibrillation did not have a significant impact on rates of sICH in AIS patients treated with IV rt-PA, ET, or both. This study supports the safety of IV rt-PA, ET, and combination therapy in the atrial fibrillation population.

Abstract P15: Does Atrial Fibrillation Impact 90-Day Outcome in Acute Ischemic Stroke Patients Treated With rt-PA and/or Endovascular Treatment?

Background: Patients with acute ischemic stroke (AIS) due to atrial fibrillation (a fib) may not have as favourable of a response to intravenous thrombolysis or endovascular treatment (ET) compared to other stroke subtypes. The purpose of this study was to compare the 90-day outcome in patients with and without a history of a fib treated with IV rt-PA and/or ET.

Method: Consecutive stroke code activations were retrospectively analyzed from January 2004-June 2020 at an academic comprehensive stroke center. Patients were included if they were treated with IV rt-PA and/or ET within 24 hours of stroke onset. Patients were stratified into the six groups: 1- No history of a fib with ET only, 2- History of a fib with ET only, 3- No history of a fib with IV rt-PA plus ET, 4- History of a fib with IV rt-PA plus ET, 5- No history of a fib with IV rt-PA only, 6- History of a fib with IV rt-PA only. Primary outcome was 90 day modified Rankin Scale (mRS) with favourable outcome defined as mRS 0-2. Baseline demographics were compared and pairwise Wilcoxon Rank was used to assess group differences followed by multinomial regression. Analyses were both unadjusted and adjusted for baseline NIHSS, age, sex, baseline blood pressure, pre-stroke mRS, smoking status, and baseline glucose.

Results: We identified 720 AIS patients who received acute treatment (IV rt-PA: n=578; ET: n=100; IV rt-PA+ET:n=18). There was a significant difference in sex (p=0.005); Hispanic ethnicity (p=0.002); current smoking (p=<0.001); current alcohol use (p=0.03), CHF (p=0.01); and age (p<0.0001) between groups. Baseline NIHSS was significantly higher in Group 4 (23, SD 8, p=<0.001). In adjusted analysis, there were significantly more patients with mRS 1 (p=0.03) and mRS 2 (p=0.01) in Group 5 compared to group 6. There was no significant difference in “favourable outcome” in adjusted analyses both between groups and in patients with and without afib overall (OR: 3.10, 95% CI: 0.19-50.97, p=0.43).

Conclusion: In this study, afib did not have a significant impact on 90-day outcome in AIS patients treated with IV rt-PA, ET, or both. This study supports the acute use of IV rt-PA in the atrial fibrillation population despite anecdotal comments that cardioembolic strokes do not improve with thrombolysis.

Encephalopathy only stroke codes (EoSC) do not result in rt-PA treatments

BACKGROUND

Isolated mental status changes as a presenting sign (EoSC+), are not uncommon stroke code triggers. As stroke alerts, they still require the same intensive resources be applied. We previously showed that EoSC+ strokes (EoSC+ Stroke+) account for 0.1-0.2% of all codes. Whether these result in thrombolytic treatment (rt-PA), and the characteristics/ risk factor profiles of EoSC+ Stroke+ patients, have not been reported.

METHODS

Retrospective analysis of stroke codes from an IRB approved registry, from 2004 to 2018, was performed. EoSC+ was defined as a NIHSS>0 for Q1a, 1b, or 1c with remaining elements scored 0. Characteristics and risk factors were compared for EoSC+, EoSC-, EoSC+ Stroke+, and rt-PA (EoSC+ Stroke+TPA+) patients.

RESULTS

EoSC+ occurred in 55/2982 (1.84%) of all stroke codes. EoSC+ Stroke+ occurred in 8/55 (14.5%) of EoSC+ codes and 8/2982 (0.27%) of all stroke codes. 6/8 (75%) of EoSC+ Stroke+ scored NIHSS=1. When comparing EoSC++versus EoSC-, Hispanic ethnicity (p=0.009), hypertension (p=0.02), and history of stroke/TIA (p=0.002) were less common in EoSC+. No demographic/risk factor differences were noted for EoSC+ Stroke+ vs. EoSC+ Stroke-. No cases of rt-PA eligibility/treatment were noted. In EoSC+ Stroke+ analysis, imaging positive stroke/intracranial hemorrhage was noted on only 3 cases (3/2982=0.10% of all stroke codes) and none were posterior stroke.

CONCLUSIONS

EoSC+ rarely results in stroke/TIA (0.27%) or stroke (0.10%), and in our analysis never (0%) resulted in rt-PA. Sub-analysis did not show missed rt-PA or posterior strokes. Understanding characteristics, and knowing that EoSC+ Stroke+ patients are unlikely to receive rt-PA, may help triage stroke resources.

Timing of symptomatic intracerebral hemorrhage after rt-PA treatment in ischemic stroke

Background

We investigated patterns in the time from recombinant tissue-type plasminogen activator (rt-PA) treatment to symptomatic intracranial hemorrhage (sICH) onset in acute ischemic stroke.

Methods

We retrospectively reviewed all admitted "stroke code" patients from 2003 to 2017 at the University of California San Diego Medical Center from a prospective stroke registry. We selected patients that received IV rt-PA within 4.5 hours after onset/last known well and had sICH prehospital discharge. sICH diagnosis was made by prospective review. Endovascular-treated patients were excluded, given the variability of practice. sICH was prospectively defined as any new radiographic (CT/MRI) hemorrhage after rt-PA treatment and any worsened neurologic examination. Time to sICH was the time from rt-PA administration start to documented STAT head CT order time with the first evidence of new hemorrhage. Charts were reviewed for examination time metrics, demographics, clinical history, and neuroimaging.

Results

sICH was identified in 28 rt-PA-only treated patients. The mean time to sICH was 18.28 hours (range 2.4-34 hours). Median time to sICH was 18.25 hours. sICH was correlated with increased age (p = 0.02) and increased NIH Stroke Scale (p = 0.01).

Conclusions

Our findings suggest that rt-PA patients have the highest risk of post rt-PA sICH within the first 24 hours after treatment. This supports monitoring of rt-PA-treated patients in specialized settings such as neuro-intensive care units or stroke units. Our findings suggest that the probability of sICH is low 36 hours post rt-PA. Future larger studies are warranted to identify the patterns of bleeding after rt-PA administration.

Mapping a Reliable Stroke Onset Time Course Using Signal Intensity on DWI Scans

BACKGROUND AND PURPOSE

Identifying a last known well (LKW) time surrogate for acute stroke is vital to increase stroke treatment. Diffusion-weighted imaging (DWI) signal intensity initially increases from onset of stroke but mapping a reliable time course to the signal intensity has not been demonstrated.

METHODS

We retrospectively reviewed stroke code patients between 1/2016 and 6/2017 from the prospective; Institutional review board (IRB) approved University of California San Diego Stroke Registry. Patients who had magnetic resonance imaging of brain from onset, with or without intervention, are included. All ischemic strokes were confirmed and timing from onset to imaging was calculated. Raw DWI intensity is measured using IMPAX software and compared to contralateral side for control for a relative DWI intensity (rDWI). LKW and magnetic resonance imaging (MRI) time were collected by chart review. Correlation is assessed using Pearson correlation coefficient between DWI intensity, rDWI, and time to MRI imaging. 1.5T, 3T, and combined modalities were examined.

RESULTS

Seventy-eight patients were included in this analysis. Overall, there was statistically significant positive correlation (.53, P < .001) between DWI intensity and LKW time irrespective of scanner strength. Using 1.5T analyses, there was good correlation (.46, P < .001). 3T MRI analysis further showed comparatively stronger positive correlation (.66, P < .001).

CONCLUSIONS

There is good correlation between DWI intensity and minutes from onset to MRI. This suggests a time-dependent DWI intensity response and supports the potential use of DWI intensity measurements to extrapolate an LKW time. Further studies are being pursued to increase both experience and generalizability.

Abstract WP378: RAcial Disparities in Ich After iv-tpA and Neurointerventional Treatment (RADIANT)

Introduction: Studies have reported ethnic/racial disparities in intravenous tPA treatment. The outcome of tPA and/or intra-arterial intervention (IA) among different ethnicities/races requires investigation. The purpose of the study was to examine the symptomatic intracranial hemorrhage (SxICH) and major systemic hemorrhage (MSH) after acute stroke treatment among different ethnicities/races.

Methods: We retrospectively reviewed all stroke code patients from an IRB- approved stroke code registry between June 2004 and June 2018. We identified patients who received either IV tPA, IA, or IV tPA+IA. Demographics, clinical presentation, co-morbidities, stroke treatments, and adverse outcomes were collected. Patients were classified into two ethnic groups - Hispanics or non-Hispanics (H/NH) and four racial groups- Asians, Black, Others (includes Native Americans and Pacific Islanders), and White (A/B/O/W).

Results: We identified 916 patients that received acute therapy (A/B/O/W: n=50/104/16/746, H/NH: n= 184/730). For those received IV tPA only (n=759), the overall SxICH rate was 4.3% (A/B/O/W: 8.1%/6.6%/8.3%/3.7%, p=0.17; H/NH: 5.7%/4.1%, p=0.42), and the MSH rate was 1.3% (A/B/O/W: 2.7%/1.1%/0%/1.3%, p=0.55; H/NH=1.4%/1.3%, p=1.00). White race was significantly correlated with lower SxICH rate after IV tPA (OR 0.07, p=0.02). There was a significant correlation between age and baseline NIHSS with SxICH (p<0.01, p=0.02, respectively). Age, INR and PTT were independent predictors of SxICH after IV tPA (OR 1.06, 46.52 and 1.18, p= 0.02, 0.04 and 0.04, respectively). For IA only (n=85), the rate of SxICH was 4.7% (A/B/O/W: 0%/0%/25%/4.5%, p=0.31; H/NH: 0%/ 6.1%, p=0.57), and 6.9% for IV tPA+IA (A/B/W: 0%/16.7%/6.6%, p=0.59; H/NH: 4.2%/8.3%, p=0.66). There was no MSH in IA only or IV tPA+IA groups.

Conclusions: White race correlated with a significantly lower rate of SxICH after IV tPA. There was no significant difference in the rate of SxICH or MSH after IV tPA, IA, or IV tPA+IA among different racial or ethnic groups in this study. Larger studies are needed to elucidate the race specific causes of these SxICH and MSH after acute stroke treatment.

Isolated Anisocoria as a Presenting Stroke Code Symptom is Unlikely to Result in Alteplase Administration

BACKGROUND

Acute stroke codes may be activated for anisocoria, but how often these codes lead to a final stroke diagnosis or alteplase treatment is unknown. The purpose of this study was to assess the frequency of anisocoria in stroke codes that ultimately resulted in alteplase administration.

METHODS

We retrospectively assessed consecutive alteplase-treated patients from a prospectively-collected stroke registry between February 2015 and July 2018. Based on the stroke code exam, patients were categorized as having isolated anisocoria [A+(only)], anisocoria with other findings [A+(other)], or no anisocoria [A-]. Baseline demographics, stroke severity, alteplase time metrics, and outcomes were also collected.

RESULTS

Ninety-six patients received alteplase during the study period. Of the 94 who met inclusion criteria, there were 0 cases of A+(only). There were 9 cases of A+(other) (9.6%). A+(other) exhibited higher baseline National Institutes of Health (NIH) Stroke Scale scores compared to A- (17 versus 7; P = .0003), and no additional differences in demographics or alteplase time metrics. Final stroke diagnosis and other outcome measures were no different between A+(other) and A-. Of the A+ patients without pre-existing anisocoria, 5 of 6 (83%) had posterior circulation events or diffuse subarachnoid hemorrhage.

CONCLUSIONS

In this exploratory analysis, zero patients with isolated anisocoria received alteplase treatment. Anisocoria as a part of the neurologic presentation occurred in 10% of alteplase patients, and was strongly associated with a posterior circulation event. Therefore, we conclude that anisocoria has a higher likelihood of leading to alteplase treatment when identified in the presence of other neurologic deficits.

Maternal insulin resistance, triglycerides and cord blood insulin are not determinants of offspring growth and adiposity up to 5 years: a follow-up study

AIMS

Metabolic dysregulation in utero may influence fetal metabolism and early growth. We previously investigated relationships between maternal indices of glucose homeostasis and triglycerides as well as cord blood insulin with offspring anthropometry up to 2 years. The aim of this analysis was to follow these relationships up to the age of 5 years.

METHODS

Associations between maternal metabolic variables of glucose and lipid metabolism measured at 32 weeks' gestation and cord blood insulin with growth and body composition of 162 offspring aged 3-5 years were explored. Both indirect (i.e. body weight, BMI percentiles, sum of four skinfold thicknesses) and direct (i.e. ultrasonography, magnetic resonance imaging in a subgroup) measurement techniques were employed.

RESULTS

Maternal metabolic indices were largely unrelated to child body composition. Cord blood insulin was negatively associated with fat mass and lean body mass at 3 years in unadjusted analyses, and the sum of four skinfold thicknesses and body fat percentage in adjusted analyses, whereas the association with lean body mass was no longer observed. An inverse relationship between cord blood insulin and weight gain up to 5 years was observed in girls only with small effect sizes.

CONCLUSIONS

Results from this follow-up do not provide convincing evidence that these markers are independently related to offspring growth and adiposity in early childhood. Although cord blood insulin was weakly inversely related to weight gain in girls at 5 years, we cannot conclude that the observed changes in outcomes are clinically meaningful. (Clinical Trials Registry No: NCT00362089).

Abstract TMP23: Shades of White: Correlation of Hyperacute DWI Intensity With Last Known Well Time

Background: Identifying a last known well (LKW) time surrogate for acute stroke is vital to increase stroke treatment. Previous research have used an MRI DWI vs. FLAIR mismatch to estimate LKW time to within 6 hours. DWI signal intensity initially increases from onset of stroke, but mapping a reliable time course to the signal intensity has not been demonstrated.

Methods: We retrospectively reviewed stroke code patients between 1/2016 and 6/2017 from the prospective, IRB approved UCSD Stroke Registry. Patients who had MRI brain from onset, with or without intervention, are included. All ischemic strokes were confirmed with ADC correlation and timing from onset to MRI was calculated. Raw DWI intensity was measured in grays (Gy) using IMPAX software and compared to contralateral side for control, for a relative DWI intensity (rDWI). LKW and MRI time were collected by chart review. Correlation was assessed using Pearson correlation coefficient between DWI intensity, rDWI, and time to MRI imaging. 1.5T, 3T, and combined modalities were examined.

Results: 97 patients were included in this analysis. Overall, there is a good correlation (0.39, p<0.001) for minutes from onset to MRI and DWI intensity. There was good correlation with the 1.5T group (0.39, p=0.001) and very good correlation with the 3T group (0.60, p=0.001). There were no significant differences in demographic or time interval between the two MRI types.

Conclusions: There is good correlation between DWI intensity and minutes from onset to MRI. This suggests a time-dependent DWI intensity response and supports the potential use of DWI intensity measurements to extrapolate a LKW time in unknown cases. Further studies in a larger dataset within the hyperacute period are being pursued to increase both experience and generalizability.

The relationship between breast milk leptin and adiponectin with child body composition from 3 to 5 years: a follow-up study

BACKGROUND

Research indicates that breast milk contains bioactive components that influence metabolism in infancy and may play a role in the prevention of obesity in early childhood. In our initial study, 147 breastfeeding mother/child pairs were followed from birth to 2 years of age to examine the relationship between breast milk leptin and total adiponectin (collected at 6 weeks and 4 months postpartum) and infant body composition. Higher breast milk total adiponectin was related to greater fat mass and weight gain in children at 1 and 2 years of age, whereas leptin showed no association.

OBJECTIVES/METHODS

In this follow-up, we examined the relationship between both adipokines and children's body weight, body mass index percentiles, sum of four skin-folds, percentage of body fat, fat mass and lean body mass at 3, 4 and 5 years of age.

RESULTS

Breast milk adipokines were largely unrelated to child anthropometric measures.

CONCLUSION

Our results do not provide significant evidence that breast milk adipokines can predict adiposity in preschool children.

Non-enhanced CT Maximum Intensity Projections for the Detection of Large Vessel Occlusions

BACKGROUND

Identification of large vessel occlusions (LVO) is important with recent guidelines supporting endovascular therapy in selected acute ischemic stroke patients. Many stroke centers perform CT angiography (CTA) in patients with suspected LVO, however this requires additional time and contrast administration. Non-enhanced CT maximum intensity projection (NECT-MIPs) may offer a rapid alternative to CTA.

METHODS

We retrospectively reviewed acute stroke patients with LVO in the UCSD Stroke Registry, presenting between 6/2014-7/2016. NECT-MIPs were evaluated for presence of LVO. Gold standard comparison was to CTA. Results were stratified by level of training (Faculty, Fellow and Acute Care Practitioners [ACPs]). Inter-rater agreement was assessed using Fleiss' Kappa Coefficient.

RESULTS

We reviewed 24 patients using NECT-MIPs for the detection of LVO. Faculty had a sensitivity and specificity of 95% & 92% for ICA/M1, 42% & 100% for M2, and 67% & 96% for basilar occlusions. Fellows and ACPs had a sensitivity and specificity of 61% & 94% for ICA/M1, 19% & 83% for M2, and 75% & 95% for basilar occlusions. Inter-rater agreement among Faculty readers was k=0.75 for ICA/M1, k=0.79 for M2 and k=0.14 for basilar occlusions. Among Fellows and ACPs, k=0.57 for ICA/M1, k=0.40 for M2, and k=0.27 for basilar occlusions.

CONCLUSIONS

NECT-MIPs have high sensitivity and specificity for the detection of LVO when compared to CTA. Inter-rater agreement is fair and higher amongst more experienced reviewers. These results suggest that NECT-MIPs may be helpful to streamline the identification of LVO and reduce door to needle and door to intervention times.

Abstract TP50: Non-contrast CT Maximum Intensity Projections (MIPs) for the Detection of Large Vessel Occlusion (LVO)

Background: Identification of LVO is becoming increasingly important with recent guidelines supporting endovascular therapy in selected patients with acute ischemic stroke (AIS).

Non-contrast CT scans are generally used to assess for stroke or hemorrhage in acute stroke code evaluations. CT angiograms (CTA) can be used to assess for LVO but require additional time and contrast administration. Some hospitals lack the resources to acutely obtain and interpret CTAs. Non-contrast CT MIPs may be an alternate modality to detect LVO.

Methods: We retrospectively reviewed patients with AIS in our UCSD Stroke Registry, presenting between 6/2014-7/2016 that received a MIPs, generated from non-contrast CT scans, and a CTA. MIPs were evaluated by a group of stroke specialists (3 Faculty, 2 Fellows, 2 Acute Care Practitioners [ACPs]). No clinical information was provided. Gold standard comparison was to CTA. Results were stratified by subgroup based on level of training. Inter-rater agreement was assessed using Fleiss’ Kappa Coefficient.

Results: 24 scans were reviewed (12 with LVO, 12 without LVO).

Using MIPs for the detection of LVO, the Faculty subgroup had a sensitivity and specificity of 81% and 86% for any LVO, 95% and 92% for ICA/M1, 42% and 100% for M2 and 67% and 96% for basilar occlusions. The Fellows and ACPs subgroup had a sensitivity and specificity of 77% and 81% for any LVO, 61% and 94% for ICA/M1, 19% and 83% for M2 and 75% and 95% for basilar occlusions.

Inter-rater agreement among Faculty readers was k=0.58 for the detection of any LVO, k=0.75 for ICA/M1, k=0.79 for M2 and k=0.14 for basilar occlusions. Among Fellows and ACPs, k=0.48 for any LVO, k=0.57 for ICA/M1, k=0.40 for M2, and k=0.27 for basilar occlusions.

Conclusions: Non-contrast CT MIPs have high sensitivity and specificity for the detection of LVO when compared to CTA. Inter-rater agreement between readers of MIPs is good. Better results in the Faculty subgroup were likely due to more experience reviewing imaging. These results support the use of non-contrast CT MIPs for the detection of LVO to both save time and contrast exposure in patients with AIS. Further studies investigating a larger dataset, optimizing MIP parameters, and examining the utility/cost-effectiveness of this technique are being pursued.

Visual Determination of Conjugate Eye Deviation on Computed Tomography Scan Predicts Diagnosis of Stroke Code Patients

BACKGROUND

Head computed tomography (CT) is critical for stroke code evaluations and often happens prior to completion of the neurological exam. Eye deviation on neuroimaging (DeyeCOM sign) has utility for predicting stroke diagnosis and correlates with National Institutes of Health Stroke Scale (NIHSS) gaze score. We further assessed the utility of the DeyeCOM sign, without complex caliper-based eye deviation calculations, but simply with a visual determination method.

METHODS

Patients with initial head CT and final diagnosis from an institutional review board-approved consecutive prospective registry of stroke codes at the University of California, San Diego, were included. Five stroke specialists and 1 neuroradiologist reviewed each CT. DeyeCOM+ patients were compared to DeyeCOM- patients (baseline characteristics, diagnosis, and NIHSS gaze score). Kappa statistics compared stroke specialists to neuroradiologist reads, and visual determination to caliper measurement of DeyeCOM sign.

RESULTS

Of 181 patients, 46 were DeyeCOM+. Ischemic stroke was more commonly diagnosed in DeyeCOM+ patients compared to other diagnoses (P = .039). DeyeCOM+ patients were more likely to have an NIHSS gaze score of 1 or higher (P = .006). The NIHSS score of DeyeCOM+ stroke versus DeyeCOM- stroke patients was 8.3 ± 6.0 versus 6.7 ± 8.0 (P = .065). Functional outcomes were similar (P = .59). Stroke specialists had excellent agreement with the neuroradiologist (Κ = .89). Visual inspection had excellent agreement with the caliper method (Κ = .88).

CONCLUSIONS

Using a time-sensitive visual determination of gaze deviation on imaging was predictive of ischemic stroke diagnosis and presence of NIHSS gaze score, and was consistent with the more complex caliper method. This study furthers the clinical utility of the DeyeCOM sign for predicting ischemic strokes.

Total 'shrink' losses, and where they occur, in commercially sized silage piles constructed from immature and mature cereal crops

Silage 'shrink' (i.e., fresh chop crop lost between ensiling and feedout) represents losses of potential animal nutrients which degrade air quality as volatile carbon compounds. Regulatory efforts have, in some cases, resulted in semi-mandatory mitigations (i.e., dairy farmers select a minimum number of mitigations from a list) to reduce silage shrink, mitigations often based on limited data of questionable relevance to large commercial silage piles where silage shrink may or may not be a problem of a magnitude equal to that assumed. Silage 'shrink' is generally ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost during oven drying (vcoDM). As no research has documented shrink in large cereal silage piles, 6 piles ranging from 1456 to 6297tonnes (as built) were used. Three used cereal cut at an immature stage and three at a mature stage. Physiologically immature silages had generally higher (P<0.01) levels of total volatile fatty acids (especially acetic acid; P=0.01) and total alcohols (P<0.01) than did physiologically mature crops, suggesting higher carbon compound volatilization potential from immature silages. However expressed as WW, oDM and vcoDM, total shrink (as well as from where in the piles it occurred) was little impacted by crop maturity, and whole pile vcoDM shrink was only ~35g/kg. Overall, real shrink losses (vcoDM) of large well managed cereal silage piles were relatively low, and a lower potential contributor to aerosol emissions of volatile carbon compounds than has often been assumed. Losses from the silage mass and the exposed silage face were approximately equal contributors to vcoDM shrink. Mitigations to reduce these relatively low emission levels of volatile organic compounds from cereal silage piles should focus on the ensiled mass and the exposed silage face.

Dose-finding study of phototherapy on stroke outcome in a rabbit model of ischemic stroke

GOAL

While transcranial laser therapy (TLT) has been shown to improve clinical outcome in a preclinical model of ischemic stroke, optimal timing and dosing has yet to be tested adequately. The purpose of this study was to assess clinical stroke outcome in the Rabbit Small Clot Embolic Model (RSCEM) with dose escalating TLT.

METHODS

We utilized the rabbit small clot embolic stroke model (RSCEM) using dose-escalating regimens. Behavioral analysis was conducted at 24h post-embolization, allowing for the determination of the effective stroke dose (ES50) or clot amount (mg) that produces neurological deficits in 50% of a group of rabbits. Using the RSCEM, a treatment is considered beneficial if it significantly increases the ES50 compared with the control group.

FINDINGS

A significant behavioral benefit was seen at triple TLT of 111mW treatment of 2min at 2h post-embolization (6.47±1.06, n=17; p=0.03), compared with the previously used regimen (3.09±0.51, n=15).

CONCLUSION

TLT results in significant behavioral improvement when administered 2h post-embolization. Studies are warranted to evaluate this therapy in combination with thrombolysis.

'Shrink' losses in commercially sized corn silage piles: Quantifying total losses and where they occur

Silage 'shrink' (i.e., loss of fresh chopped crop between ensiling and feedout) represents a nutrient loss which can degrade air quality as volatile carbon compounds, degrade surface waterways due to seepage, or degrade aquifers due to seepage. Virtually no research has documented shrink in large silage piles. The term 'shrink' is often ill defined, but can be expressed as losses of wet weight (WW), oven dry matter (oDM), and oDM corrected for volatiles lost in the drying oven (vcoDM). Corn silage piles (4 wedge, 2 rollover/wedge, 1 bunker) from 950 to 12,204 tonnes as built, on concrete (4), soil (2) and a combination (1) in California's San Joaquin Valley, using a bacterial inoculant, covered within 24 h with an oxygen barrier inner film and black/white outer plastic, fed out using large front end loaders through an electronic feed tracking system, and from the 2013 crop year, were used. Shrink as WW, oDM and vcoDM were 90±17, 68±18 and 28±21 g/kg, suggesting that much WW shrink is water and much oDM shrink is volatiles lost during analytical oven drying. Most shrink occurred in the silage mass with losses from exposed silage faces, as well as between exposed face silage removal and the total mixed ration mixer, being low. Silage bulk density, exposed silage face management and face use rate did not have obvious impacts on any shrink measure, but age of the silage pile during silage feedout impacted shrink losses ('older' silage piles being higher), but most strongly for WW shrink. Real shrink losses (i.e., vcoDM) of large well managed corn silage piles are low, the exposed silage face is a small portion of losses, and many proposed shrink mitigations appeared ineffective, possibly because shrink was low overall and they are largely directed at the exposed silage face.

Defining mild stroke: outcomes analysis of treated and untreated mild stroke patients

Introduction

Mild deficit is a relative contraindication to administration of IV rtPA for acute ischemic stroke. However, what constitutes “mild” deficit is vague. Prior studies showed patients with mild strokes have substantial disability rates at hospital discharge and at 90 days. We investigated whether the application of a new definition altered the rates of disability overall, and assessed the effects of thrombolysis.

Methods

This analysis included all adult acute ischemic stroke patients from a prospective registry of consecutive patients (UCSD SPOTRIAS database, 2003-2014) with 90-day mRS score available who were defined as “mild” using either: NIHSS 0-5 or a TREAT Task Force definition (NIHSS 0-5 and non-disabling based on pre-specified syndromes). Dichotomized 90-day mRS were compared between treated and untreated patients using the two definitions.

Results

Of 802 ischemic stroke patients with mRS scores available, 184 had baseline mRS(0) and met TREAT criteria; 45(24.5%) were rtPA-treated. Among treated patients, 35.6% had 90-day mRS(2-6), versus 28.8% in the untreated group, a non-significant difference after adjusting for baseline NIHSS (p=0.47). None of the 45 treated patients had symptomatic hemorrhage. Outcomes were similar using the simpler NIHSS 0-5 definition.

Conclusions

About one-third of mild stroke patients were not functionally independent at 90 days, irrespective of treatment or mild definition applied, calling into question the treatment efficacy of IV rtPA for mild strokes as well as what constitutes an appropriate definition of “mild”. Randomized studies are necessary to determine rtPA treatment efficacy in mild stroke patients.

The "DeyeCOM Sign": Predictive Value in Acute Stroke Code Evaluations

BACKGROUND

Rapid diagnosis in stroke is critical. Computed tomography is often performed initially, even before a neurologic examination. Gaze deviation has been correlated with stroke diagnosis in some cohorts. Conjugate gaze deviation on stroke code imaging, the "DeyeCOM sign," may have emergency stroke care implications.

METHODS

We evaluated stroke code imaging from the University of California, San Diego database (2007-2013) for "DeyeCOM sign" diagnostic and predictive utility. Patients were grouped as DeyeCOM+ if conjugate gaze deviation was noted. The differences were assessed using the Fisher exact test for categorical and the Wilcoxon rank-sum test for continuous variables.

RESULTS

We evaluated 342 patients; 106 (31%) were DeyeCOM+. Mean age was 63. The most common diagnoses in the DeyeCOM+ group were ischemic stroke (50.94%), transient ischemic attack (8.49%), other (8.49%), somatization (6.6%), and hemorrhage (5.66%). The National Institutes of Health Stroke Scale was greater in stroke patients than that in nonstroke (8.2 versus 3.8; P < .0001), and in DeyeCOM+ compared with DeyeCOM- (6.8 versus 5.6; P = .03). DeyeCOM+ patients were more likely to have a +gaze score (26.4% versus 9.8%; P < .0001), and +gaze patients were more likely to have final stroke diagnosis (26.0% versus 3.6%; P < .0001). There was no overall difference between groups in final stroke diagnosis; however, patients with deviation of 15° or more were more likely to have final diagnosis stroke (63.9% versus 47.9%; P = .03).

CONCLUSIONS

DeyeCOM+ patients scored higher and were more likely to have +gaze on the stroke scale, and deviation of 15° or more was correlated with final diagnosis stroke. In current environments, there is pressure to complete stroke evaluations rapidly. Reliable imaging information obtained early (such as gaze deviation on scan correlating with scale score and final stroke diagnosis) could augment decision making even with negative imaging.

Abstract T P275: Quantification of Potential Bias in Databases That Require Consent in Acute Stroke

Background: The stroke database at our institution includes patients who gave consent and are followed up at 90 days after acute stroke and a group entered into our registry in whom only limited data is available under a consent waiver. We explore the potential bias that is introduced by the requirement to obtain consent.

Methods: We included patients with an admission diagnosis of acute ischemic stroke. For each of the groups (database versus registry), we analyzed age, sex, race/ethnicity, hypertension, diabetes, history of atrial fibrillation, smoking status, pre-stroke mRS, baseline NIHSS, presence of aphasia, and use of IV rt-PA. We used Wilcoxon Rank-sum test for continuous and Fisher's Exact for categorical variables.

Results: A total of 1800 patients were included (database 849, registry 951). In the database versus registry 84.6% were white versus 79.9% (p=0.006); baseline NIHSS was 8.6±8.1 versus 10.6±9.2; aphasia 38.6% versus 44% (p=0.03); pre-stroke disability (mRS >1) 21.5% versus 30% (p<0.0001) and IV rt-PA use 47.7% versus 26.5% (p<0.0001). There was no difference in age, sex, smoking status, the frequency of diabetes, atrial fibrillation, hypertension and ethnicity (Hispanic) between the groups.

Conclusion: In our comparison between a database requiring consent and a registry utilizing consent waiver, we found that the database included more whites, patients with lower NIHSS, fewer patients with aphasia and pre-stroke disability. Requiring consent in acute stroke may introduce bias against minorities and patients with more severe stroke and/or aphasia. Future projects should take this into consideration and focus on reducing bias.

Abstract T P64: Change in UCSD Stroke Center IV tPA Treatment Patterns Over the Last Decade

Background: IV tPA has been approved since 1995, and treatment practices have changed over time. Especially in the last decade, the treatment has become more widely adopted and is offered to more patients. We explored the UCSD stroke center database specifically to assess changes in treatment patterns over time. These could affect clinical trial design, performance and outcomes as the prediction of such is often based on historical information.

Methods: We included all patients with acute ischemic stroke (AIS) from the UCSD Stroke Center Database between 2004 and 2014 (comparing 2004-2009 - Group 1 vs. 2010-2014 - Group 2). We assessed age, sex, race/ethnicity, pre-stroke disability, frequency of IV tPA use (<3 hours between 2004 and 2009; 25 stroke. Good outcomes were defined as discharge to home or acute rehabilitation.

Results: We identified 1,816 patients with AIS from 2004 to 2014 (Group 1: 988, Group 2: 828) and found no difference in age, sex, diabetes, pre-stroke mRS and outcomes between the groups. Mean±SD NIHSS was lower in Group 2 (11.6±8.2 versus 3.6±13.3; p=0.0005) and overall IV tPA use more frequent (332/828 (36.3%) versus 328/988 (33.2%) - p=0.0024). More patients with mild (22.1% versus 12.3%; p=0.0009) and moderate (45.6% versus 41.3%; p=0.02) receive IV tPA. There was no difference in tPA use for patients with NIHSS >14.

Discussion: IV tPA use increased over time, especially in mild and moderate stroke. This may in part be a function of increased treatment times (4.5 hours) or overall increased acceptance of this therapy. It is important to consider these treatment changes over time when planning for research protocols and use caution when comparing current data to historical controls.

Abstract T P74: Mild Stroke in a Telemedicine Network: Identification, Treatment, and Outcomes

Introduction: "Mild" stroke is not well defined, but is a relative contraindication for the administration of IV rtPA. Advances in telemedicine have allowed for specialized practitioners to observe the examination, rather than rely on the on-scene examiner. We investigated whether there were differences in rates of identification, treatment, and outcomes of mild stroke patients in the phone compared to the video arms of a telestroke network.

Methods: The STRokE DOC trials were prospective, randomized, outcome-blinded trials comparing video telemedicine to phone-only evaluations, which assessed eligibility for IV rtPA and correctness of decision-making for 2 hubs and 6 spokes. This analysis included all adult acute ischemic stroke patients from the STRokE DOC trials who were defined as “mild” using a recent definition from the TREAT Task Force. Rates of ICH, mortality, and dichotomized 90-day mRS scores were compared between the video and phone arms.

Results: Mild stroke accounted for 32% and 29% of the video and phone arms, respectively. The two groups had similar baseline characteristics except hypertension (higher rate in video arm). Of the video mild stroke patients, 13% had poor outcome (mRS>1) compared to 24% of the phone arm (p=0.45). There were no symptomatic ICH or deaths. Among IV rtPA treated mild stroke patients, all of the video arm had good outcome, versus 25% of the phone arm. Of 100 non-treated patients, 34 were excluded because of "too mild" a deficit (TMT). In the phone arm, 7 of these did not meet the TREAT-derived criteria for mild stroke (p=0.03). One TMT patient in the phone arm had poor outcome.

Conclusions: Mild stroke made up a third of the patients in each group. Some TMT patients in the phone arm did not meet the criteria for mild stroke; their subtle findings may not have been conveyed adequately over the phone. Among IV rtPA treated patients, the phone arm had worse outcomes. The results raise concern regarding accuracy of predicting outcomes for mild stroke patients, especially when based on a phone description. The study numbers were small, so conclusions cannot be definitively made. Future studies are necessary to determine decision making factors within the telemedicine process that influence treatment outcomes among mild stroke patients.

Is the ICH score a valid predictor of mortality in intracerebral hemorrhage?

PURPOSE

The intracerebral hemorrhage (ICH) score utilizes a 0- to 6-point scoring system to predict 30-day mortality in ICH patients. The purpose of this analysis was to (a) validate the ICH score in an international, heterogeneous population of ICH patients; and (b) assess the usefulness of a 72-h ICH score.

DATA SOURCES

Analyses were based on data from 399 patients in the Novo Nordisk trial F7ICH-1371. The ICH score's ability to predict mortality was determined by calculating the sensitivity, specificity, and positive predictive value (PPV).

CONCLUSIONS

Both the baseline and 72-h ICH score had high specificity but low sensitivity resulting in an overall PPV of 57%-76%. Specificity of the ICH score was higher in the baseline ICH score (95%) as compared to the 72-h score (89%). Sensitivity of the ICH score was higher in the 72-h ICH score (75%) as compared to the baseline score (36%).

IMPLICATIONS FOR PRACTICE

The baseline ICH score provides reasonable PPV while the 72-h score provides higher sensitivity. ICH scores obtained at baseline and/or 72 h are valid and may help practitioners to more accurately predict 30-day mortality in ICH patients.

The future direction of the adult heart allocation system in the United States

Ensuring equitable and fair organ allocation is a central charge of the United Network for Organ Sharing (UNOS) as the Organ Procurement and Transplantation Network (OPTN) through its contract with the Department of Health and Human Services (DHHS). The OPTN/UNOS Board initiated a reassessment of the current allocation system. This paper describes the efforts of the OPTN/UNOS Heart Subcommittee, acting on behalf of the OPTN/UNOS Thoracic Organ Transplantation Committee, to modify the current allocation system. The Subcommittee assessed the limitations of the current three-tiered system, outcomes of patients with status exceptions, emerging ventricular assist device (VAD) population, options for improved geographic sharing and status of potentially disenfranchised groups. They analyzed waiting list and posttransplant mortality rates of a contemporary cohort of patient groups at risk, in collaboration with the Scientific Registry of Transplant Recipients to develop a proposed multi-tiered allocation scheme. This proposal provides a framework for simulation modeling to project whether candidates would have better waitlist survival in the revised allocation system, and whether posttransplant survival would remain stable. The tiers are subject to change, based on further analysis by the Heart Subcommittee and will lead to the development of a more effective and equitable heart allocation system.

Association of Hispanic ethnicity with acute ischemic stroke care processes and outcomes

BACKGROUND

Few studies have examined the actual hospital arrival mode, emergency department (ED) care processes, and early outcomes in Hispanic vs non-Hispanic acute ischemic stroke (AIS) patients. We evaluated processes and prognosis by Hispanic ethnicity among AIS patients encountered in urban setting.

METHODS

We retrospectively reviewed prospectively-collected data on 1,117 AIS patients presenting within 12 hours of ictus to five hospitals in a tertiary-level stroke center network in San Diego, California. Variables of interest included pre-hospital factors, ED care processes, and favorable outcome (day-90 modified Rankin Scale [mRS] score of 0-1); all of which were adjusted for pre-specified covariates in a multivariable logistic regression model.

RESULTS

There were 192 Hispanic AIS patients (17.2% of cohort) encountered from June 2004 to March 2011. Hispanic patients were significantly more likely to be younger, female, and diabetic. Hispanic patients arrived by ambulance (vs other arrival modes) less frequently (adjusted OR .56; 95% CI: .38-.81), trended toward a longer time of stroke onset to treatment decision (351.6 vs. 320.02 minutes, P=.07), and experienced a favorable day-90 outcome less often (adjusted OR .52, CI: .28-.96). However, for the day-90 outcome, there was no interaction between ambulance arrival and Hispanic ethnicity (P=.5614).

DISCUSSION

Hispanic AIS patients in this study were less likely to arrive at the hospital by ambulance, and experienced half the odds of a favorable outcome compared to others. Strategies to boost ambulance utilization among Hispanic AIS patients and identify contributors to this worrisome outcome disparity are needed.

rLOAD: does sex mediate the effect of acute antiplatelet loading on stroke outcome

BACKGROUND

Biologic sex can influence response to pharmacologic therapy. The purpose of this proof-of-concept study was to evaluate the medicating effects of estrogen in the efficacy of acute antiplatelet loading therapy on stroke outcome in the rabbit small clot embolic model.

METHODS

Female and male (20/group) New Zealand White rabbits were embolized to produce embolic stroke by injecting small blood clots into the middle cerebral artery via an internal carotid artery catheter. Two hours after embolization, rabbits were treated with standard dose antiplatelet loading (aspirin 10 mg/kg plus clopidogrel 10 mg/kg). Primary outcome measures were platelet inhibition, behavioral outcome P 50 (the weight of microclots (mg) that produces neurologic dysfunction in 50% of a group of animals), and effect of endogenous estrogen on outcome.

RESULTS

For the first time in a non-rodent model of stroke, it was found that higher endogenous estrogen levels resulted in significantly better behavioral outcome in female subjects (r s -0.70, p < 0.011). Platelet inhibition in response to collagen, arachidonic acid, and adenosine diphosphate (ADP) was not significantly different in females with higher vs. lower estrogen levels.

CONCLUSIONS

Behavioral outcomes are improved with females with higher endogenous estrogen levels treated with standard dose antiplatelet loading. This is the first non-rodent study to demonstrate that higher endogenous estrogen levels in female rabbits appear to be neuroprotective in ischemic stroke. This research supports the further study of the effect of endogenous estrogen levels on outcome with standard dose antiplatelet loading in stroke patients not eligible for revascularization therapies.

Abstract W P180: Sex Differences in Acute Stroke Evaluation

Introduction: Prompt acute stroke evaluation is essential for optimal treatment. Women may receive delayed evaluation and treatment; consistent data is unavailable. We analyzed sex differences in acute stroke evaluation.

Methods: We evaluated consecutive Code Stroke patients from the UCSD SPOTRIAS database, excluding inpatients. Subgroups included acute ischemic stroke (AIS) and IV r-tPA treated patients. Wilcoxon and Fisher’s Exact Test compared baseline variables between sexes. Times from onset to arrival, arrival to: stroke code, neurological exam, brain imaging, laboratory, decision, and treatment were compared between sexes using linear regression, adjusting for pre-specified covariates: age, smoking, atrial fibrillation, hypertension, glucose, baseline NIHSS, pre-stroke mRS, and onset to arrival time. Multivariable logistic regression models evaluated 90 day mRS, adjusted as above. (Good outcome: mRS 0-2)

Results: Of 3,214 patients (48.3% female), women were older (p<0.0001), with more atrial fibrillation (p<0.01), and higher pre-stroke mRS (p<0.0001) compared to men. Smoking history was more common in men in all analyses (p<0.0001). Evaluation times and 90-day outcomes were similar, except women had longer arrival to neurological exam times (41.5 ± 52.8 min vs. 37.5 ± 68.9 min; p=0.014). In total, 1,476 patients had AIS (45.8% female). Of all women with Code Strokes, 43.5% were diagnosed with AIS while 48.1% of men were diagnosed. In the AIS subset, evaluation times were not significantly different, though women with AIS were more likely to have poor outcome after adjusting for pre-specified covariates (54.5% vs. 39.4%, p=0.017). There were 532 patients diagnosed with AIS and treated with tPA (49.8% female). There were no significant differences in evaluation times or 90-day outcome.

Discussion: In this single center experience, evaluation and treatment times did not differ between men and women except for the time from arrival to neurological exam. While any sex based difference is concerning, further multicenter trials are needed to better understand any possible sex based stroke evaluation and treatment bias.

Abstract T MP85: Does Pre-Stroke Disability Affect Acute Evaluation, Treatment and Outcomes After Stroke?

Background: Pre-stroke disability is expected to influence outcome in stroke. Enrollment of clinical trials in stroke is frequently limited to patients with pre-stroke modified Rankin score (mRS) of ≤2. Our objective is to explore evaluation, treatment and outcomes in stroke patients with pre-stroke mRS 3-5.

Methods: We included all patients from the acute stroke code database (UCSD SPOTRIAS from Mar 2005 - Jul 2013 with known pre-stroke mRS, baseline NIHSS and 90-day mRS and confirmed diagnoses: Acute ischemic stroke (AIS), transient ischemic attack (TIA), intracerebral hemorrhage (ICH). We assessed onset time to arrival, arrival time to- (CT, exam, treatment, decision) and outcomes (90-day mRS, discharge destination) by pre-stroke disability stratified by mRS (Group 1: mRS 3-5, Group 2: mRS 0-2). Good outcome was defined as discharge to home or acute rehab, or return to pre-stroke mRS or better.

Results: A total of 572 patients with AIS (416, 73%), TIA (133, 23%), and ICH (23, 4%) were identified. Group 1patients with pre-stroke mRS 3-5 (69, 12%) were older (mean ± SD: 80 ±11 versus 68 ± 7 y, p<0.001), mostly women (70% vs. 41%, p<0.001), had history of hypertension (84% vs. 71%, p=0.029), prior cerebrovascular disease (43% vs. 28%, p=0.012), neuropsychiatric disease (23% vs. 6%, p<0.001), other CNS disease (35% vs. 6%, p<0.001), and higher baseline NIHSS (mean ± SD: 14.9 ± 9 vs. 6.4 ± 8, p<0.001) compared to Group 2. Majority (61%) of Group 1 had a mRS score of 3 followed by mRS 4 (38%). There were no differences in onset to arrival, arrival time to- stroke code initiation, neuro exam, CT imaging, and treatment decision between groups. No difference in stroke patients eligible for IV thrombolysis (44% vs. 36%, p=0.23) or treated with IV r-tPA. Discharge to home or acute rehab was less frequent in ischemic stroke patients of Group 1 (44% vs. 77%, p<0.001). However, patients returning to a pre-stroke mRS score or better at 90 days was not different between groups (40% vs. 47%, p=0.39). C onclusions: Using return to baseline as good outcome measure demonstrated patients with pre-stroke disability benefit from acute evaluation and treatment. Patients with pre-stroke moderate disability (mRS 3) may particularly be considered for inclusion in future clinical trials.

Abstract T P9: Predictive Value of NIHSS for the Hyperdense Artery Sign

Background: Anecdotally, many use a total NIHSS value to determine need for endovascular involvement in acute ischemic stroke patients. However, no NIHSS value has been shown to be predictive of artery occlusion. We aim to identify an NIHSS threshold that predicts vessel occlusion as measured by hyperdense artery sign

Methods: The UCSD SPOTRIAS prospectively collected database was analyzed for patients diagnosed with acute ischemic stroke (AIS) who received a noncontrast CT on initial evaluation. Groups with and without hyperdense artery sign were compared via Wilcoxon-rank sum and Fisher’s Exact Test. ROC analysis was conducted to determine AUC and threshold NIHSS to predict artery occlusion. Sensitivity and Specificity, and positive and negative predictive value were calculated.

Results: Of 1617 acute ischemic stroke patients, hyperdense artery sign was present in 204 (12.6%). The hyperdense artery group had more women (52.9% vs 44%, p=0.02), higher rate of atrial fibrillation (38.2% vs 22.2%, p<0.0001), and lower rate of prior cerebrovascular disease (23.1% vs 31.7%, p=0.016). Mean NIHSS was 17.7 in those with hyperdense artery, compared with 9 in those without (p<0.0001). In ROC analysis, the best NIHSS threshold to predict hyperdense artery was 12.5 with AUC of 77.73% (95% CI 74.57, 80.89), sensitivity of 72.5%, and specificity of 73.7%. Positive Predictive Value was 28.5; Negative Predictive Value was 94.9.

Conclusions: In our AIS population, a NIHSS cutoff of 12.5 was most predictive of artery occlusion, as measured by hyperdense artery sign. The AUC was only moderate and the PPV low at 28.5%. The NPV, however was high, which indicates that patients with NIHSS less than 12-13 are very unlikely to show hyperdense artery signs. This may guide the decision to consider the need for further vessel imaging and endovascular therapies.

Antiplatelet loading improves behavioral outcome in a rabbit model of stroke

BACKGROUND AND PURPOSE

No approved acute therapy exists for thousands of patients with ischemic stroke who present ineligible for thrombolytics. The purpose of this proof-of-concept study was to evaluate the efficacy of acute antiplatelet loading on stroke outcome in the rabbit small clot embolic model.

METHODS

Sixty male New Zealand white rabbits were embolized via small clots into the middle cerebral artery. Two hours later, animals were treated with (1) aspirin (5 mg/kg; n=20); (2) usual dual antiplatelet loading (aspirin 10 mg/kg+clopidogrel 10 mg/kg; n=20); or (3) high-dose dual antiplatelet loading (aspirin 10 mg/kg+clopidogrel 30 mg/kg; n=20). The coprimary outcomes were as follows: (1) platelet inhibition and (2) behavioral outcome as measured by the P50 (milligrams of clot that leads to neurological dysfunction in 50% of animals in a group).

RESULTS

There was a significant difference in 3-hour arachidonic acid and ADP (P<0.011); 6-hour collagen and ADP (P<0.01, P<0.01); and 24-hour collagen, arachidonic acid, and ADP (P=0.02, P<0.01, P<0.01) platelet inhibition. The behavioral outcome was significantly better in the usual dual antiplatelet loading versus aspirin group (P=0.02).

CONCLUSIONS

This study suggests that usual dual antiplatelet loading is clinically beneficial in a validated model of acute stroke. Study of usual dual antiplatelet loading in acute stroke is warranted to provide treatment to stroke victims ineligible for current therapies.

Abstract TP69: Minimum NIHSS Score To Qualify For IV tPA

BACKGROUND: Frequently patients with ischemic stroke are excluded from IV tPA therapy because of mild deficits. Often a minimal score on the NIHSS is used to identify mild stroke patients, but some argue to specially weight motor and language deficits. We examined the outcomes of patients with Acute Ischemic Stroke (AIS) who did not receive IV tPA using four definitions of a “mild” deficit using the total and itemized NIHSS at baseline with the aim to identity patients with a mild deficit that highly predicts good outcome when not treated with thrombolysis. Additionally we examined if any single item on the NIHSS in mild stroke patients predict poor outcomes.

METHODS: We included all adult patients with mild (NIHSS 0-4) AIS from the UCSD SPOTRIAS Database from 2004-2012; excluded patients who received thrombolysis (IV or IA) or had a pre-stroke mRS >0. We analyzed baseline demographics (age, sex, race, HTN, DM, afib), total NIHSS, NIHSS items (normal or abnormal) and 90-day mRS. We evaluated four definitions of mild deficits: 1) total NIHSS 0-4; 2) NIHSS 0-4 AND arm (Q5) AND leg weakness (Q6) 0-1, AND aphasia (Q9) 0-1; 3) NIHSS 0-4 AND Q5,6,9=0; 4) NIHSS 0-4 AND Q5+6+9<2. Good outcome was defined as 90-day mRS 0-1.

RESULTS: A total of 147 patients were included (definition #1), under mild #2 we identified 111, #3 78 and #4 106 patients. Good outcome was achieved in 70.8%, 70.3, 74.4% and 70.8% of each definition. No NIHSS item (0 vs >0) correlated with poor outcome in mild patients.

CONCLUSION: We found no significant difference in outcome prediction when weighing motor and language deficit over the overall NIHSS <5. In the patients with mild stroke, no specific NIHSS scoring item predicted poor outcome.

Abstract 16: EARLY: EMS Prenotification Augments Stroke Code Timepoints But Rigorous Training is Needed for Larger Yield in stroke

Background: rtPA for AIS is time sensitive, requiring efficient and coordinated acute care. We evaluated time to evaluation, stroke diagnosis, treatment rate, and 90 day outcome in patients with stroke team prenotification by EMS and those identified after arrival.

Methods: The UCSD SPOTRIAS prospectively collected database was analyzed for patients with stroke team prenotification by EMS and other patients seen in stroke code, excluding inpatient codes. Multivariable regression models used outcome of interest as independent variable. Models were adjusted for pre-specified covariates: pre-stroke mRS, age, gender, smoking, baseline NIHSS and glucose. Time differences between groups were analyzed using Wilcoxon Rank Sum Tests.

Results: We assessed 2867 patients, with EMS prenotification in 643 (22.4%). Assessment at 90 days was obtained in 216 with prenotification and 807 others. Those with prenotification were older (mean 68 vs 66, p=0.0498), with higher pre-stroke mRS (p=0.0243), NIHSS (10.9 vs 8.5, p< 0.0001) and glucose (139 vs 135, p=0.0013). Prenotification led to shorter time to imaging, decision, and IV rtPA treatment (all p<0.0001). No difference was seen in IV rtPA treatment rate (18% EMS prenotifications vs 16% others). When controlling for baseline characteristics, stroke was diagnosed more frequently in patients without EMS prenotification (OR 1.31, 95% CI 1.08-1.58, p=0.0057). Poor outcome (mRS 3-6) was seen more frequently in prenotification patients (45.83% vs 35.32%, p=0.006, NS after adjusting for baseline covariates).

Conclusions: In the UCSD experience, EMS prenotification leads to faster evaluation critical in stroke. Prenotification occurred in patients at a medically worse baseline, but did not result in higher rates of final stroke diagnosis or IV rtPA. With improved education, accurate identification of AIS patients may improve, further expediting care and improving treatment and outcomes.