Krishnaiah, Balaji

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: Patients with cervical artery dissection (CeAD) may experience a recurrent dissection, but its frequency, risk factors, and clinical implications are not well defined. We aimed to determine the risk, associated factors, and clinical impact of recurrent CeAD. METHODS: The STOP-CAD study (Antithrombotic Treatment for Stroke Prevention in Cervical Artery Dissection) was a multicenter international retrospective observational study of patients with CeAD treated between January 2015 and June 2022. Recurrent dissection was defined as a CeAD occurring at least 7 days after the diagnosis of the index event that affects a different artery or a different segment of the same artery. Patients were followed from day 7 up to 2 years. The absolute risk of recurrent CeAD over time was calculated using Kaplan-Meier survival estimates. Multivariable logistic and Cox regression models were used to assess predictors of CeAD recurrence. RESULTS: Of the 4023 patients included in STOP-CAD, 3836 (median age 46 years, 45% women) were eligible for this analysis. During a median (interquartile range) follow-up of 295 (97–720) days, 88 (2.29%) patients had a CeAD recurrence. Median time-to-recurrent CeAD was 53 (interquartile range, 18–157) days. The estimated risk of recurrent CeAD at 2 years was 3.22% (95% CI, 2.59%–4.00%). In multivariable analyses, younger age (adjusted odds ratios, 0.98 [95% CI, 0.96–0.99]), migraine (adjusted odds ratio, 1.88 [95% CI, 1.14–3.07]), and fibromuscular dysplasia (adjusted odds ratio, 2.90 [95% CI, 1.66–5.06]) were associated with CeAD recurrence, while presenting with an ischemic stroke was associated with a lower likelihood of recurrence (adjusted odds ratio, 0.47 [95% CI, 0.29–0.75]). These associations with CeAD recurrence over time were confirmed by Cox regression analyses. Among the 88 patients with recurrent CeAD, only 5 had accompanying ischemic events (3 strokes, 2 transient ischemic attacks). CONCLUSIONS: In this retrospective study, recurrent CeAD was uncommon, approximately half of the events were diagnosed within the first 2 months of the index event, and recurrent events rarely caused new ischemic events. Younger age, migraine, absence of ischemic stroke at presentation, and signs of fibromuscular dysplasia may help identify high-risk patients.

BACKGROUND: Intracranial atherosclerosis (ICAS) is associated with an increased risk of early recurrent ischemic stroke. We evaluated whether biomarkers of impaired distal perfusion—specifically, anterior circulation borderzone infarct, and hypoperfusion mismatch volume—were associated with recurrent ischemic stroke within 90 days. METHODS: The BIORISK ICAS (Biomarkers and Recurrence Risk in Symptomatic Intracranial Atherosclerosis) is a multicenter retrospective international study (35 sites) that included hospitalized patients with symptomatic ICAS (50%–99% luminal stenosis of the intracranial vertebral, basilar, distal internal carotid, or proximal middle cerebral artery) from January 2019 to June 2024. The primary outcome was recurrent ischemic stroke in the territory of the symptomatic artery within 90 days. In the primary analysis, the exposure was an acute anterior circulation borderzone infarct. In secondary analysis of the subset with presentation within 72 hours of last known normal and perfusion imaging completed, the exposure of interest was prespecified as hypoperfusion mismatch volume at T max (time to maximum) threshold of 6 seconds, dichotomized at the Youden index. We performed multivariable Cox regression to test associations between exposure variables and the outcome, adjusting for clinically relevant variables and those associated with the outcome ( P <0.1). RESULTS: Of 2050 patients with symptomatic ICAS, 1737 (84.7%) presented within 72 hours of symptom onset, among whom 509 (29.3%) underwent perfusion imaging. The primary analysis included 1891 patients; 174 (9.2%) patients had recurrent ischemic stroke in the symptomatic arterial territory. In adjusted Cox regression models, there was an association between anterior circulation borderzone infarct and recurrent ischemic stroke at 90 days (adjusted hazard ratio, 1.40 [95% CI, 1.02–1.93]). In the perfusion imaging analysis, hypoperfusion mismatch of ≥10 mL was associated with recurrent ischemic stroke (adjusted hazard ratio, 1.83 [95% CI, 1.03–3.28]). CONCLUSIONS: Biomarkers of impaired distal perfusion, anterior circulation borderzone infarct, and hypoperfusion mismatch were associated with increased risk of recurrent ischemic stroke. These findings support the use of perfusion imaging in ICAS as well as future trials investigating early reperfusion in high-risk patients with ICAS.

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: Patients presenting with cervical artery dissection (CAD) are at risk for subsequent ischemic events. We aimed to identify characteristics that are associated with increased risk of ischemic stroke after initial presentation of CAD and to evaluate the differential impact of anticoagulant versus antiplatelet therapy in these high-risk individuals. METHODS: This was a preplanned secondary analysis of the STOP-CAD study (Antithrombotic Treatment for Stroke Prevention in Cervical Artery Dissection), a multicenter international retrospective observational study (63 sites from 16 countries in North America, South America, Europe, Asia, and Africa) that included patients with CAD predominantly between January 2015 and June 2022. The primary outcome was subsequent ischemic stroke by day 180 after diagnosis. Clinical and imaging variables were compared between those with versus without subsequent ischemic stroke. Significant factors associated with subsequent stroke risk were identified using stepwise Cox regression. Associations between subsequent ischemic stroke risk and antithrombotic therapy type (anticoagulation versus antiplatelets) among patients with identified risk factors were explored using adjusted Cox regression. RESULTS: In all, 4023 patients (mean age was 47.4 years; 44.5% were women) were included. By day 180, subsequent ischemic stroke occurred in 5.3% of the cohort. In adjusted Cox regression, factors associated with increased risk of subsequent ischemic stroke were prior history of ischemic stroke (adjusted hazard ratio [aHR], 7.31 [95% CI, 1.61–33.13]; P =0.010), presentation within 7 days from first symptoms (aHR, 3.04 [95% CI, 1.04–8.91]; P =0.043), infarct on baseline imaging (aHR, 9.85 [95% CI, 3.65–26.58]; P <0.001), and occlusive dissection (aHR, 2.34 [95% CI, 1.03–5.34]; P =0.043). Only patients with occlusive dissection demonstrated a reduced risk of subsequent ischemic stroke when treated with anticoagulation versus antiplatelets (aHR, 0.36 [95% CI, 0.16–0.80]; P =0.01). CONCLUSIONS: In this post hoc analysis of the STOP-CAD study, several factors associated with subsequent ischemic stroke were identified among patients with CAD. Furthermore, we identified a potential benefit of anticoagulation in patients with CAD with occlusive dissection. These findings require validation by meta-analyses of prior studies to formulate optimal treatment strategies for specific high-risk CAD subgroups.