Omran, Setareh Salehi

Abstract Introduction Cervical arterial dissections (CeAD) can involve either single (sCeAD) or multiple (mCeAD) arteries. Whether the involvement of a single versus multiple arteries is associated with outcomes remains unclear. We aimed to study associations between the number of affected arteries and clinical, imaging and outcome parameters. Patients and methods Patients with CeAD from the STOP-CAD multicenter registry study were included. Clinical, imaging, treatment and outcome parameters were compared between patients with sCeAD and mCeAD. Regression analyses were performed to identify associations with multi-arteries involvement. Results Overall, 3858 STOP-CAD patients were included in this analysis and 443 (11.5%) had mCeAD. The presence of mCeAD was associated with age (adjusted odds ratio [aOR] 95% confidence intervals [95% CI] 0.99; (0.98–1.00)), female sex (aOR 1.5; 95% CI 1.17–1.91), recent upper respiratory infection (aOR 2.25; 95% CI 1.55–3.27), presence of connective tissue disease (aOR 3.11; 95% CI 2.32–4.17), severe arterial stenosis (aOR 1.95; 95% CI 1.95–2.58), intracranial extension (aOR 1.47; 95% CI 1.04–2.09), vertebral artery involvement (aOR 2.50; 95% CI 1.94–3.22) and presence of dissecting aneurysm (aOR 2.59; 95% CI 1.95–3.42). In adjusted analyses, mCeAD was not associated with clinical outcomes (ischemic stroke, mortality, and sICH; all p > 0.05). Conclusions mCeAD does not appear to increase risk of subsequent stroke as compared to sCAD despite baseline risk factors suggestive of vasculopathy. mCeAD patients who did develop a stroke presented with milder strokes and less often had vessel occlusions compared to those with sCeAD. The presence of mCeAD did not impact outcomes.

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.

Objective Cervical artery dissection (CeAD) may be limited to the extracranial extradural space or extend to the intradural space. Intradural extension can potentially increase the risk of stroke and subarachnoid hemorrhage. However, the factors associated with intradural extension and its impact on clinical outcome remain unclear. Methods This was a secondary analysis of the STOP‐CAD observational, multi‐center study. Patients with CeAD and intradural extension (CeADid) were compared with those with pure CeAD extradural dissections (CeADed) using multiple regression analyses. Results Of 4,023 patients with CeAD, 534 (13.3%) had CeADid. In comparison to patients with CeADed, those with CeADid more often had clinical overt stroke or transient ischemic attack (TIA) at presentation, acute infarcts on imaging, a vertebral artery affected, and severe stenosis of the involved vessel ( p < 0.001 for all). In contrast, carotid involvement and complete occlusions were more frequent in patients with CeADed ( p < 0.001 for both). CeADid was associated with a shift in the distribution of scores on the modified Rankin Scale (mRS) toward worse functional outcome (odds ratio [OR] = 0.76, 95% confidence interval [CI] = 0.62–0.92) but the odds for favorable outcomes (mRS = 0–2) did not differ between the groups after appropriate adjustments on multivariate analysis. CeADid was independently associated with higher mortality at 180 days on multivariate analysis (adjusted OR = 2.84, 95% CI = 1.50–5.38). Interpretation CeADid is associated with more severe clinical presentation, a shift toward less favorable outcomes, and higher mortality rates. These findings suggest that CeADid may represent a high‐risk type of CeAD. ANN NEUROL 2026;99:1189–1197

BACKGROUND: Small, randomized trials of patients with cervical artery dissection showed conflicting results regarding optimal stroke prevention strategies. We aimed to compare outcomes in patients with cervical artery dissection treated with antiplatelets versus anticoagulation. METHODS: This is a multicenter observational retrospective international study (16 countries, 63 sites) that included patients with cervical artery dissection without major trauma. The exposure was antithrombotic treatment type (anticoagulation versus antiplatelets), and outcomes were subsequent ischemic stroke and major hemorrhage (intracranial or extracranial hemorrhage). We used adjusted Cox regression with inverse probability of treatment weighting to determine associations between anticoagulation and study outcomes within 30 and 180 days. The main analysis used an as-treated crossover approach and only included outcomes occurring with the above treatments. RESULTS: The study included 3636 patients (402 [11.1%] received exclusively anticoagulation and 2453 [67.5%] received exclusively antiplatelets). By day 180, there were 162 new ischemic strokes (4.4%) and 28 major hemorrhages (0.8%); 87.0% of ischemic strokes occurred by day 30. In adjusted Cox regression with inverse probability of treatment weighting, compared with antiplatelet therapy, anticoagulation was associated with a nonsignificantly lower risk of subsequent ischemic stroke by day 30 (adjusted hazard ratio [HR], 0.71 [95% CI, 0.45–1.12]; P =0.145) and by day 180 (adjusted HR, 0.80 [95% CI, 0.28–2.24]; P =0.670). Anticoagulation therapy was not associated with a higher risk of major hemorrhage by day 30 (adjusted HR, 1.39 [95% CI, 0.35–5.45]; P =0.637) but was by day 180 (adjusted HR, 5.56 [95% CI, 1.53–20.13]; P =0.009). In interaction analyses, patients with occlusive dissection had significantly lower ischemic stroke risk with anticoagulation (adjusted HR, 0.40 [95% CI, 0.18–0.88]; P interaction =0.009). CONCLUSIONS: Our study does not rule out the benefit of anticoagulation in reducing ischemic stroke risk, particularly in patients with occlusive dissection. If anticoagulation is chosen, it seems reasonable to switch to antiplatelet therapy before 180 days to lower the risk of major bleeding. Large prospective studies are needed to validate our findings.

BACKGROUND: It is uncertain whether antiplatelets or anticoagulants are more effective in preventing early recurrent stroke in patients with cervical artery dissection. Following the publication of the observational Antithrombotic for STOP-CAD (Stroke Prevention in Cervical Artery Dissection) study, which has more than doubled available data, we performed an updated systematic review and meta-analysis comparing antiplatelets versus anticoagulation in cervical artery dissection. METHODS: The systematic review was registered in PROSPERO (CRD42023468063). We searched 5 databases using a combination of keywords that encompass different antiplatelets and anticoagulants, as well as cervical artery dissection. We included relevant randomized trials and included observational studies of dissection unrelated to major trauma. Where studies were sufficiently similar, we performed meta-analyses for efficacy (ischemic stroke) and safety (major hemorrhage, symptomatic intracranial hemorrhage, and death) outcomes using relative risks. RESULTS: We identified 11 studies (2 randomized trials and 9 observational studies) that met the inclusion criteria. These included 5039 patients (30% [1512] treated with anticoagulation and 70% [3527]) treated with antiplatelets]. In meta-analysis, anticoagulation was associated with a lower ischemic stroke risk (relative risk, 0.63 [95% CI, 0.43 to 0.94]; P =0.02; I 2 =0%) but higher major bleeding risk (relative risk, 2.25 [95% CI, 1.07 to 4.72]; P =0.03, I 2 =0%). The risks of death and symptomatic intracranial hemorrhage were similar between the 2 treatments. Effect sizes were larger in randomized trials. There are insufficient data on the efficacy and safety of dual antiplatelet therapy or direct oral anticoagulants. CONCLUSIONS: In this study of patients with cervical artery dissection, anticoagulation was superior to antiplatelet therapy in reducing ischemic stroke but carried a higher major bleeding risk. This argues for an individualized therapeutic approach incorporating the net clinical benefit of ischemic stroke reduction and bleeding risks. Large randomized clinical trials are required to clarify optimal antithrombotic strategies for management of cervical artery dissection.

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.

Background: Multiple randomized clinical trials failed to show benefit of anticoagulation over antiplatelets in the secondary prevention for embolic stroke of undetermined source (ESUS). However, the benefit of combination antithrombotic regimens remains unexplored in the same patient population. Methods: This is a subgroup analysis of a multicenter retrospective observational cohort of consecutive adult patients with ESUS (n=27 sites, 2015-2024). Comparisons were made between patients treated with single (SAPT) or dual antiplatelet therapy (DAPT), exclusive anticoagulation (AC) (direct oral anticoagulant, vitamin K antagonist, low molecular weight heparin) and combination anticoagulation and antiplatelet therapy initiated within the first 7 days of index stroke. The primary composite outcome of recurrent ischemic stroke, major bleeding, or death was assessed using unadjusted and adjusted Cox proportional hazards regression. Secondary outcomes were individual outcomes of recurrent ischemic stroke, major bleeding, or death. Results: Of the 2201 included patients, 1456 (66.1%) were on SAPT, 527 (23.9%) were on DAPT, 195 (8.8%) were on exclusive AC and 23 (1.0%) were on AC+AP (all of which were on DAPT). Patients treated with AC+AP were older (median 66 years [IQR 51-78]), more likely to have history of hypertension, stroke, hyperlipidemia, PFO and left atrial enlargement. Compared to SAPT, all treatment strategies were associated with similar risk of the primary outcomes in the unadjusted and adjusted cox regression. Similarly, there was no difference in individual outcomes including recurrent stroke, major bleeding and death in the adjusted cox regression. However, there was an increased risk of major bleeding with AC+AP in the unadjusted cox regression (HR 4.0, [95% CI 1.2-12.8], p=0.02) but not in the adjusted model when compared to SAPT. Also, DAPT was associated with lower risk of death than SAPT in the unadjusted model (HR 0.61 [95% CI 0.4-0.8],p=0.005) but not the adjusted model. Additionally, when adjusted by the HASBLED score, there was no difference in major bleeding when AC+AP was compared to SAPT. Conclusion: Over 90% of ESUS patients in this cohort were prescribed SAPT or DAPT. Antithrombotic therapy with DAPT, exclusive AC, or AC+AP was not associated with any lower risk of recurrent ischemic stroke, major bleeding and death compared with SAPT in an unselected cohort of ESUS patients.

Introduction: Four randomized clinical trials have not demonstrated the superiority of anticoagulation over antiplatelet therapy in the prevention of recurrent embolic stroke of undetermined source (ESUS). In this multicenter observational cohort study, we evaluated long-term outcomes associated with various antithrombotic strategies according to potential embolic sources. Methods: A multicenter retrospective observational cohort of consecutive adult patients with ESUS was queried (n=27 sites). Comparisons were made between patients treated with single or combination antiplatelet therapy versus anticoagulation (direct oral anticoagulant, vitamin K antagonist, low molecular weight heparin) with or without antiplatelet therapy initiated within 7 days of stroke. The primary composite outcome of recurrent stroke, major bleeding, or death was assessed using unadjusted and adjusted Cox proportional hazards regression, with clustering by site. Causal inference was assessed using inverse probability of treatment weighted regression adjustment (IPTWRA), accounting for propensity for antiplatelet treatment, with effect estimates summarized as the average treatment effect (ATE) over time (in days). Adjusted models accounted for age, stroke severity, vascular risk factors, and major categories of potential embolic sources. Results: Of the 2201 included patients (n=218 treated with anticoagulation) followed over a median of 564 days (interquartile range [IQR] 154-1124), the median age was 65y (IQR 54-74) and 49.8% were female. Patients treated with anticoagulation were older with more frequent previous stroke, concomitant left ventricular dysfunction, and more severe deficits. Over 4541 person-years of follow-up, the annualized incidence rate of the primary outcome was 14.6% (95% confidence interval [CI], 13.6%-15.8%). Compared to anticoagulation, antiplatelet(s) use was not associated with a lower risk of the primary outcome in the adjusted Cox model (HR 0.91, 95% CI, 0.64-1.29) or in the IPTWRA model (average treatment effect 0.14, 95% CI, -1376.6 to 1376.9). Major bleeding events trended toward significance in the adjusted Cox model (HR 0.51, 95% CI 0.25-1.04) but were no different with IPTWRA (ATE 58.9, 95% CI, -125.4 to 243.2). Conclusions: These results validate the observations of randomized trials indicating a lack of benefit of anticoagulation over antiplatelet therapy in ESUS. A more detailed analysis of heterogeneity of treatment effect is under way.