Collin J. Culbertson

Background: Although the embolic stroke of undetermined source (ESUS) construct was proposed as a unifying concept for embolic‐appearing strokes without an identified cause, it includes patients with diverse and often unrecognized underlying mechanisms. This study investigates the differential rate of recurrent stroke according to the completeness of neurodiagnostic testing in a diverse multicenter cohort. Methods: This was a retrospective analysis of a multicenter observational cohort study (n=27 sites). ESUS was categorized into 3 groups: (1) established mechanism after further workup (ESUS‐E), (2) comprehensive diagnostic workup without an identified cause (ESUS 2.0), and (3) no advanced workup. The primary outcome of recurrent ischemic stroke was compared between ESUS with established mechanism and ESUS 2.0 versus ESUS with no advanced workup and was assessed using adjusted Cox proportional hazards models. Results: Among 2281 patients, the mean age was 65 years, and 50.1% were men. 694 (30.4%) classified as ESUS‐E, 1,243 (54.5%) classified as ESUS‐NAW, and 344 (15.1%) as ESUS 2.0. The ESUS 2.0 group had a significantly lower risk of recurrent stroke than both the group with ESUS with no advanced workup (adjusted hazard ratio [aHR], 0.31 [95% CI, 0.13–0.76]) and the group with ESUS with established mechanism (aHR, 0.35 [95% CI, 0.15–0.85]). Within the group with ESUS with established mechanism, cancer (aHR, 5.33 [95% CI, 2.09–13.63]) and nonstenosing atherosclerotic disease or arch atheroma (aHR, 3.40 [95% CI, 1.18–9.83]) were associated with significantly increased risk of recurrence when compared with the group with ESUS 2.0. Conclusions: These findings demonstrate a lower risk of recurrent stroke in patients classified as ESUS 2.0 than reported in prior ESUS trials and highlight the importance of age‐appropriate advanced diagnostic evaluation. Registration: URL: https://www.clinicaltrials.gov . Identifier: NCT06398366.

Background and ObjectivesMultiple clinical trials have failed to show benefit of anticoagulation over antiplatelets in preventing recurrent stroke among patients with embolic stroke of undetermined...

BACKGROUND: Left ventricular (LV) dysfunction is a potential cardioembolic source of ischemic stroke, but its role in recurrent stroke risk and treatment response remains unclear. We explore whether LV injury associates with the risk of recurrent stroke and modifies the association between anticoagulation and stroke recurrence using real-world data. METHODS: We performed a multicenter, retrospective study of Cardiac Abnormalities in Stroke Prevention and Recurrence cohort across 27 US sites. Patients with LV ejection fraction ≥20% were included. LV injury, defined as LV ejection fraction 20% to 40% and wall motion abnormality, was the primary exposure and treatment effect modifier. The treatment of interest was anticoagulant versus antiplatelet therapy. The composite outcome included recurrent stroke, major bleeding, or death. Outcomes were evaluated using unadjusted and inverse probability weighting adjusted Cox proportional hazards models, with treatment effect modification tested by LV injury status. RESULTS: Among 2685 patients enrolled, 2328 with complete data were analyzed (median age, 65 years; 49.8% female; median follow-up, 1.6 years). LV injury was present in 310 patients (13.3%). Overall, 535 events occurred: 258 recurrent ischemic strokes, 28 hemorrhagic strokes, 67 major hemorrhages, and 256 deaths. LV injury was associated with a higher unadjusted risk of the primary outcome (hazard ratio [HR], 1.51 [95% CI, 1.21–1.87]), though nonsignificant after inverse probability weighting adjustment (adjusted HR, 1.29 [95% CI, 0.97–1.70]). In the LV injury subgroup, anticoagulation versus antiplatelet therapy was associated with a lower risk of the primary outcome (adjusted HR, 0.24 [95% CI, 0.10–0.59]), relative to the non-LV injury subgroup (adjusted HR, 1.28 [95% CI, 0.83–1.95]; p[LV-interaction], 0.001). Similar interactions were seen for EF 20% to 40% (versus >40%; adjusted HR, 0.19 [95% CI, 0.04–0.86]; p[LV-interaction], 0.001) and wall motion abnormality (versus no wall motion abnormality; adjusted HR, 0.33 [95% CI, 0.15–0.73]). CONCLUSIONS: After cryptogenic stroke, anticoagulation in those with LV injury was associated with lower rates of recurrent stroke, major bleeding, and death. These findings warrant confirmation in a dedicated randomized controlled trial. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT06398366.

Background: Intracranial occlusions in embolic stroke of undetermined source are histopathologically similar to cardiac sources of embolism. Whether patients with embolic stroke of undetermined source and intracranial occlusion benefit from anticoagulation is unknown. Methods: A multicenter retrospective cohort of adults with cryptogenic stroke was queried for patients with proximal or medium/distal vessel occlusion. The primary outcome was recurrent ischemic stroke, which was assessed in unadjusted and adjusted Cox proportional hazards models and repeated following 1:1 propensity score matching and biweight kernel density matching. Results: Of the 2328 patients who were followed over a median of 1.31 years (interquartile range, 0.34–2.85), 999 (42.6%) had an intracranial occlusion. When compared with patients without an intracranial occlusion, those with an occlusion had fewer atherosclerotic vascular risk factors, more severe symptoms, and less severe cerebral microvascular disease. The rate of recurrent stroke was similar between patients with versus without an intracranial occlusion (6.8%/year [95% CI, 5.7–8.2] versus 7.0%/year [95% CI 6.0–8.1]; adjusted hazard ratio [HR], 1.09 [95% CI, 0.77–1.55]). There was no association between occlusion and recurrent stroke in the adjusted propensity score matching (HR, 1.01 [95% CI, 0.64–1.59]) or kernel density models (HR, 0.95 [95% CI, 0.62–1.45]). There was no interaction between occlusion and treatment with anticoagulation, sex, age, or high‐risk sources of embolism for the primary outcome in the unmatched and matched analyses. Conclusions: Intracranial occlusion in patients with embolic stroke of undetermined source is not associated with a greater risk of recurrence when compared with patients without an intracranial occlusion. There was no difference in rate of recurrent stroke with anticoagulation when stratified by presence or absence of occlusion.

Background and Purpose: Magnetic resonance imaging (MRI) is safe for most patients with cardiovascular implantable electronic devices (CIEDs). However, patients presenting with acute ischemic stroke or transient ischemic attack (AIS/TIA) who have CIEDs may undergo MRI less frequently than patients without devices. We assessed contemporary use of MRI for patients with AIS/TIA and the effect of a recent coverage revision by the Center for Medicare and Medicaid Services (CMS) on MRI utilization. Methods: Using Optum^® claims data from January 2012 to June 2019, we performed an interrupted time series analysis of MRI utilization during AIS/TIA hospitalizations with the April 2018 CMS coverage revision serving as the intervention. For patients treated after the coverage revision, we used multivariable logistic regression to determine the association between lack of CIED and MRI utilization for AIS/TIA. Results: We identified 417,899 patient hospitalizations for AIS/TIA, of which 30,425 (7%) had a CIED present (CIED vs non-CIED patients: age 77.6 ± 9.8 vs 72.7 ± 12.3 years; 45.5% vs 54.3% female). From 2012 to 2019, annual MRI utilization increased from 3% to 20% for CIED patients and 58% to 66% for non-CIED patients. The CMS coverage revision was associated with a 4.2% absolute additional increase in MRI utilization for CIED patients. Non-CIED patients treated after the CMS coverage revision were substantially more likely than CIED patients to undergo MRI (adjusted OR 6.7, 95% CI: 6.3-7.1, P<.001). Conclusions: MRI utilization has increased for stroke patients with CIEDs but remains far lower than in similar patients without devices.

This Viewpoint describes the role of neurologists in implementing improved access to magnetic resonance imaging for patients with cardiovascular implantable ele

Huang H, et al. J Clin Neurol. 2016 Jan;12(1):75-78. http://dx.doi.org/10.3988/jcn.2016.12.1.75