Citations

Background: Left ventricular (LV) injury is a cardioembolic etiology of ischemic stroke. We aimed to 1) evaluate recurrent stroke risk among patients with cryptogenic stroke and LV injury, and 2) determine if there is a treatment effect with anticoagulation in this population. Methods: We analyzed the multicenter, retrospective Cardiac Abnormalities in Stroke Prevention and Recurrence cohort of patients with cryptogenic ischemic stroke. The exposure was LV injury defined by 1) LV ejection fraction (EF) 20-40% and/or 2) LV wall motion abnormality (hypokinesis or akinesis). The primary composite outcome included recurrent stroke, major bleeding, or death. Cox proportional hazard models were built and sequentially adjusted for 1) age and sex (Model 1), and 2) age, sex, race, ethnicity, anti-thrombotic use, and vascular risk factors (Model 2). We then assessed if there was heterogeneity in treatment effect by LV injury status with an interaction term of LV injury and oral anticoagulation use in Model 2. Results: Of 2,641 patients in CASPR, the analytic cohort included 2,191 patients with complete exposure and outcome data (median age 65 years, 49.8% female, median follow-up 1.55 years). There were 113 (5.2%) patients with LV injury (median LVEF 30%, interquartile range 25-34%). There were 559 incident events (321 recurrent strokes [288 ischemic], 71 major hemorrhages, 250 deaths). Among patients with LV injury, 15.9% were prescribed an anticoagulant within 7 days of index stroke (vs 9.6% without LV injury, p=0.03). The unadjusted risk of the primary outcome was non-significantly higher among patients with LV injury vs without (HR 1.40; 95% confidence interval [CI], 0.98-2.00), but became significant in Model 1 (HR 1.50; 95% CI, 1.21-1.85) and in Model 2 (HR 1.35, 95% CI, 1.11-1.64). In the LV injury subgroup, anticoagulation vs antiplatelet therapy was associated with a significant reduction in the primary outcome (HR 0.63, 95% CI, 0.43-0.94). In patients without LV injury, anticoagulation was associated with a higher risk of the composite outcome (HR 4.35, 95% CI, 1.69-11.16, p[interaction]=0.002). Conclusion: In this observational study, there was an increased risk of the primary outcome which included recurrent stroke among patients with cryptogenic stroke and LV injury. Anticoagulation use in LV injury is associated with a significant reduction in the risk of the primary outcome. These findings warrant confirmation in a dedicated randomized controlled trial.

Introduction: Malignancy represents an important subgroup of embolic stroke of undetermined source (ESUS). We aim to compare infarct features, potential embolic sources, and long-term outcomes in ESUS patients with and without malignancy. Methods: In this pre-specified secondary analysis of the Cardiac Abnormalities in Stroke Prevention and Recurrence (CASPR) retrospective cohort study, active cancers were identified by site investigators and adjudicated as malignant if they were non-squamous or non-basal cell skin cancers. We compared the prevalence of various potential embolic sources (e.g., patent foramen ovale, left ventricular dysfunction, post-stroke atrial fibrillation) among patients with and without malignancy. The risk of recurrent stroke, major bleeding, or death was evaluated using adjusted Cox proportional hazards models, accounting for age, sex, vascular risk factors, competing potential embolic sources, and initial treatment with anticoagulation versus non-anticoagulant (e.g., antiplatelet) regimen. Results: Of the 2201 patients followed over a median of 564 days, 236 (10.7%) were diagnosed with cancer at the time of stroke. Patients with malignancy were older, more frequently hypertensive and did not differ with regards to prevalence of specific infarct patterns or potential cardiac embolic sources. No difference was observed in the composite outcome of recurrent stroke, major bleeding, or death (adjusted HR 1.02, 95% CI, 0.71-1.46). Age (adjusted HR per year 1.02, 95% CI, 1.01-1.03), baseline stroke severity (adjusted HR 1.03 per NIHSS point, 95% CI, 1.01-1.05), prior stroke (adjusted HR 1.68, 95% CI, 1.38-2.05), and multi-territorial infarct pattern (adjusted HR 1.67, 95% CI, 1.33-2.08) were significantly associated with this composite outcome, but anticoagulation was not. There was a nominally lower rate of major bleeding with malignancy (adjusted HR 0.45, 95% CI, 0.19-1.04), a significantly higher rate of death (adjusted HR 1.58, 95% CI, 1.09-2.30), but no significant difference in recurrent ischemic stroke (p=0.31). Conclusions: Patients with malignancy and ESUS had higher mortality but did not differ in recurrent stroke risk or major bleeding when compared to patients without malignancy. Anticoagulation was not independently associated with better outcomes. Further analysis of infarct topology and risk factors may better identify patients for whom anticoagulation may benefit.

Introduction: Heart failure with low ejection fraction (EF) is a known risk factor for stroke. Low EF is associated with increased risk of thrombus formation and is accompanied with 2 to 3 fold increased risk of stroke. This can happen even in the absence of atrial fibrillation. Hypothesis: Our hypothesis was that size of the stroke will be larger in patients with reduction in EF as compared with cardioembolic strokes in preserved EF. The worse the EF, the more stagnation of blood and poor cardiac output leading higher risk of thrombus formation. It’s also likely that the group with reduced EF form a larger thrombus leading to larger stroke as compared to the group with preserved EF. Methods: For our analysis, we retrospectively reviewed charts for 49 acute ischemic stroke patients without atrial fibrillation. We used transthoracic echocardiogram to determine the EF. There are 25 patients with preserved EF, cutoff > 50%. There were 24 patients in reduced EF group. Both groups were matched for age and cardiovascular risk factors. Infarct volume was manually calculated from T1 MRI using BrainLab software. Results: There is an inverse correlation between EF and infarct volume (r=-.283, p=.048) meaning patients with reduced EF had greater infarct volume. Median infarct volume is higher in reduced EF group (median volume = 36 cm 3 ) compared to patients with preserved EF (median volume = 11 cm 3 ) (p=.117). Conclusions: In our patient’s sample, there seems to be an inverse correlation between EF and size of stroke. Patients with reduced EF were associated with larger strokes. Larger studies need to be performed to establish a correlation.

Introduction: A significant burden of acute ischemic stroke (AIS) can be decreased by timely administration of tissue plasminogen activator (tPA). Door-to-needle (DTN) time is a nationally reported quality measure for patients with AIS. In a majority of primary and comprehensive stroke centers, acute stroke care is provided by teams comprising of trainees (residents/fellows). Adaptive learning is a well-studied paradigm to improve the quality of medical education. Conceptually, this model consists of four parts starting with planning, and subsequently involving learning, assessing and adjusting. It is a learner driven process. Hypothesis: Utilizing the adaptive learning model will reduce DTN time in AIS patients who present to the emergency department of a rural, tertiary care medical center staffed by neurology residents. Methods: Successive patients who received IV tPA for AIS in the emergency department of our academic medical center between January 1, 2014 and December 31, 2016 were included in the study. During months 1-18 (pre-intervention) DTN times were not shared with residents. During months 19-36 of study (post-intervention), we utilized our monthly stroke meeting to share DTN times anonymously. Discussions were held and emphasis was placed on the processes which led to shorter DTN times. Residents assessed responses, planned changes, and made adjustments in real time. Descriptive statistics were used to analyze the data. Results: A total of 313 patients received IV tPA during the study period (150 pre-intervention, 171 post intervention period). After the implementation of the quality improvement initiative, mean and median DTN time significantly reduced from 54.7 minutes to 43.0 minutes (p<0.0001) and 52 minutes to 39 minutes (p<0.0001) respectively. Conclusions: Our study exemplifies the success of the adaptive learning model in the care of patients with acute ischemic stroke. Our quality intervention led to significantly reduced DTN times. Furthermore, this educational initiative provided residents with objective feedback about their performance - one of the requirements of the accredited council of graduate medical education (ACGME).