Abstract WP074: Impaired Cerebrovascular Reactivity Predicts Stroke Risk in Asymptomatic High-Grade Carotid Stenosis or Occlusion: A Systematic Review and Meta-Analysis
Background: The management of asymptomatic high-grade carotid stenosis remains challenging, particularly in identifying individuals at highest risk for hypoperfusion-related stroke. Impaired cerebrovascular reactivity (CVR) has emerged as a potential predictor of future cerebrovascular events. Objective: To perform a systematic review and meta-analysis to quantify the association between impaired CVR and the risk of ipsilateral ischemic stroke or TIA in patients with asymptomatic high-grade carotid stenosis/occlusion. Methods: A systematic literature search of PubMed, Embase and Scopus was conducted from inception till July 2025. Eligible studies included asymptomatic patients with ≥70% carotid stenosis or occlusion who underwent CVR assessment and reported ipsilateral ischemic stroke or TIA outcomes. Pooled relative risks (RR) with 95% confidence intervals (CIs) were calculated using a random-effects model. Forest plots were generated, and heterogeneity was assessed using the chi-square test and the I 2 statistic. Results: Six prospective observational studies including a total of 361 patients with asymptomatic high-grade carotid stenosis/occlusion (mean age 70.4 years; 73.6% male; 71.2% with hypertension; 28.6% with diabetes; 29.6% current or former smokers) were included in the analysis. Of these, 120 patients had impaired CVR and 241 had preserved CVR. Transcranial Doppler (TCD) was the most frequently used modality to assess CVR, with acetazolamide or CO 2 as the vasodilatory stimulus. Following CVR assessment, patients were monitored for a weighted mean follow-up of 26.2 months (range: 21.5 to 42.5 months). The incidence of ipsilateral ischemic stroke or TIA was 14.2% in patients with impaired CVR versus 2.1% in those with preserved CVR (RR 3.98; 95% CI 1.62–9.76; P = 0.003; Figure 1). When limited to ipsilateral ischemic stroke alone, the incidence was 21.4% in the impaired CVR group compared to 4.3% in the preserved CVR group (RR 3.35; 95% CI 1.54–7.25; P = 0.002; Figure 2). Conclusions: Impaired CVR is associated with a 3- to 4-fold increased risk of ipsilateral ischemic stroke or TIA in patients with high-grade carotid stenosis/occlusion. CVR assessment may help stratify risk and guide individualized management in this population.
Abstract TMP69: Prevalence and Risk Factors of Seizures in Cerebral Amyloid Angiopathy: a multi-year health system-wide case-control study
Introduction: Cerebral Amyloid Angiopathy (CAA) is caused by the progressive deposition of β-amyloid in the walls of small to medium-sized cerebral vessels. Although seizures represent a debilitating manifestation of CAA, little is known about their prevalence or associated factors. We aim to fill this gap by determining the prevalence of seizures in CAA and identify factors associated with an increased risk of seizures. Methods: We identified consecutive patients with CAA, evaluated within the Mayo Clinic health system between January 2010 and December 2023 using the ICD-10 code. Data on demographics and comorbidities were compared between those with and without seizures using the chi-square test for categorical variables and independent samples t-test for continuous variables. Odds ratios (OR) were estimated after adjusting for age, sex, and race in multivariable logistic regression. Results: We included 1,914 patients with CAA with a mean age of 75.4 ± 8.6 years, of whom 52.3% were female and 87.5% were white. Seizures were observed in 347 patients (18.1%). Individuals with seizures were significantly younger (mean age 67.7 ± 9.1 vs. 77.2 ± 7.5 years, p < 0.001). Multivariable modeling identified alcohol abuse (OR 1.92, 95% CI 1.03-3.56, p=0.04), diabetes mellitus (OR 2.14, 95% CI 1.13-4.06, p=0.02), hypertension (OR 1.79, 95% CI 1.33 - 2.41, p= <0.001), liver disease (OR 1.75, 95% CI 1.14-2.69, p=0.01), and ischemic stroke (OR 1.33, 95% CI 1.01-1.74, p=0.04) as independently associated with an increased risk of seizures. Conclusion: We found that seizures affect nearly one in five patients with CAA. Also, comorbidities such as alcohol abuse, diabetes mellitus, hypertension, liver disease, and ischemic stroke were found to be significantly associated with an increased risk of seizures. Longitudinal studies are warranted to confirm these risk factors, some of which may be modifiable.
Erythrocyte Sedimentation Rate (ESR) as a Predictor of White Matter Lesion (WML) Progression (P2-5.031)
Introduction: Collateral cerebrovasculature is important for the survival of penumbral tissue in patients with large vessel occlusive (LVO) stroke, and adequate collateralization is associated with favorable outcomes. The presence of cerebral microbleeds (CMB) have been implicated in vessel wall remodeling and impaired vasoreactivity. We investigated whether the presence of deep and/or lobar CMB predicts poor collateral recruitment in patients with LVO stroke who underwent thrombectomy (MT). Methods: We performed a retrospective, single-center study of adults who presented with LVO stroke and had MT between January 2012-June 2020. CT angiography of head prior to MT was used to assess collateral status with poor status defined as ≤50% filling and good status as >50% filling. CMBs were assessed using T2*-weighted gradient echo or susceptibility weighted magnetic resonance images. Location of CMB was further characterized as deep vs. lobar using consensus definitions. Poor stroke outcome was defined as modified Rankin Scale (mRS) ≥3 at 90 days. Multivariable logistic regressions were performed to evaluate the associations between CMB, CMB types (lobar, deep, lobar+deep) and poor collaterals after adjusting for vascular risk factors. Results: Consecutive 151 subjects were included (mean age 68±15 years, 47% women), with a median NIHSS of 18. CMB were identified in 57 subjects (37.4%). Of these, 20.5% had lobar CMB, 5.3% had deep CMB and 11.9% had combined lobar & deep CMB. Patients with CMB had higher odds of having poor collaterals compared to those without CMB (OR 1.56, 95% CI 1.09-2.23, P=0.015). The association of CMB with poor collaterals was strongest in patients with combined lobar & deep CMB (OR 4.78, 95% CI 1.43-15.93, P=0.011), compared with those with exclusively deep CMB (OR 2.78, 95% CI 0.44-17.62, P=0.278) or lobar CMB (OR 0.52, 95% CI 0.19-1.38, P=0.188). Patients with poor collaterals were more likely to have poor outcome compared with those with good collaterals (48.4% vs. 31.0%, P=0.03). Conclusion: Cerebral microbleeds are independently associated with poor collateral recruitment when adjusted for traditional vascular risk factors. Further study is warranted to elucidate the differential effects of CMB types on collateral recruitment.
Abstract TMP61: Induced Hypertension in Acute Ischemic Stroke: Systematic Review and Meta-Analysis
Background and Objectives: It is unclear whether induced hypertension in acute ischemic stroke (AIS) may improve long-term outcomes. We conducted a systematic review and meta-analysis to compare the safety and efficacy of induced hypertension vs standard medical care in patients presenting with acute ischemic stroke within 72 hours of symptom onset. Methods: Two reviewers systematically searched PubMed using the prespecified terms “induced hypertension” or “blood pressure augmentation” plus “ischemic stroke” for clinical trials that reported functional independence (mRS 0-2) at 90 days. The safety outcome was symptomatic intracranial hemorrhage (sICH). Pooled odds ratio (OR) and 95% CI across trials were synthesized using fixed-effect model based on Mantel-Haenszel methods. Forest plots were constructed. Results: Three clinical trials with 270 AIS patients treated with induced hypertension (n=126) or standard medical care (n= 144) were included. Mean age was 66.6 years, 35.2% were women, and the mean initial NIHSS was 7.5. The rate of functional independence at 90 days was higher in patients treated with induced hypertension (70.6%) versus control (54.9%) (OR 1.88; 95% CI 1.13-3.11; p=0.01). sICH did not differ between patients treated with induced hypertension (<1%) versus control (<1%) (OR 1.03; 95% CI 0.14-7.45; p=0.98). Discussion: Among patients presenting with acute ischemic stroke with 72 hours of symptoms onset, induced hypertension resulted in better functional outcome at 90 days than standard medical care and did not increase risk of sICH. Large RCTs to test this observation are ongoing and needed to guide clinical practice.