Meschia, James F.

Importance Cerebral hemodynamic impairment in patients with asymptomatic internal carotid artery (ICA) stenosis is associated with reduced cognition. It is uncertain whether revascularization might be an effective treatment for cognitive impairment in these patients. Objective To test whether any cognitive benefit from revascularization of high-grade, asymptomatic ICA stenosis varies based on the degree of baseline cerebral hemodynamic impairment. Design, Setting, and Participants This substudy was conducted within a multicenter phase 3 randomized clinical trial. Adults (aged 35-86 years) without dementia with eighth-grade education or higher and unilateral asymptomatic ICA stenosis greater than or equal to 70% were enrolled from January 2018 to July 2024 at 61 sites in North America (last follow-up in July 2025). Of 607 participants screened from 2485 in CREST-2, 392 were enrolled. Magnetic resonance or computed tomographic perfusion imaging tested for baseline hemodynamic impairment defined by delayed time-to-peak (TTP) arrival of intravenous contrast in the hemisphere ipsilateral minus contralateral to the stenotic artery. Intervention Carotid revascularization (endarterectomy or stenting) plus intensive medical management (IMM) vs IMM alone. Main Outcomes and Measures The primary outcome was the difference in composite cognitive z score over 1 year based on 5 cognitive tests. The primary analysis tested for an interaction between treatment group (revascularization vs IMM alone) and degree of baseline hemodynamic impairment among those with reduced baseline cognition (cognitive z score ≤−1.0 SD). Results Of 392 participants enrolled (mean age, 71 years; 125 [32%] females), 61 were excluded for missing baseline imaging and 40 for missing cognitive examinations or other covariates, leaving 291 with complete data. Fifty-one had reduced cognition at baseline (25 in the revascularization group and 26 in the IMM alone group). TTP ranged from no interhemispheric TTP delay to a more-than-2-second delay. Mean (SD) cognitive z scores were −1.36 (0.51) at baseline and −1.17 (0.47) at 1 year in the revascularization group and −1.34 (0.83) at baseline and −1.01 (0.97) at 1 year in the IMM alone group. The primary analysis showed no difference in cognition by treatment group over 1 year, adjusting for treatment group × hemodynamic status interaction and other covariates (adjusted difference in cognitive z score, −0.15 SD [95% CI, −0.54 to 0.24]). The interaction was not significant (β estimate = 0.018 [95% CI, −0.025 to 0.061]; P = .40). Conclusions and Relevance In this substudy of a randomized clinical trial, there was no differential effect of revascularization vs IMM alone on cognition over 1 year by cerebral hemodynamic status among those with baseline reduced cognition, suggesting that revascularization does not improve cognitive dysfunction by restoring flow to the brain in chronic asymptomatic carotid stenosis. Trial Registration ClinicalTrials.gov Identifier: NCT03121209

Background Studies suggest that hypoperfusion from heart failure (HF) may contribute to cognitive decline. However, the relationship between the HF subtypes and cognition remains poorly described in real‐world populations. Methods We conducted a cross‐sectional study of patients aged ≥18 years seen at the Mayo Clinic in 2022 who underwent echocardiogram and cognitive assessment within 1 year. HF was classified per the 2022 American Heart Association as no HF, HF with preserved ejection fraction (EF), HF with mildly reduced EF, and HF with reduced EF. Cognitive impairment was categorized using the Montreal Cognitive Assessment score as normal (≥26), mild (18–25), and moderate to severe (<18). Linear regression assessed EF–Montreal Cognitive Assessment correlation and logistic regression the association between HF subtypes and cognitive dysfunction, adjusting for age, sex, race, and vascular risk factors. Results A total of 1592 patients met inclusion criteria (mean age, 75.7±13.8 years; 48.5% women). Lower EF was associated with worse cognitive performance (postadjustment β=0.033, P =0.013). Patients with HF with reduced EF and patients with HF with preserved EF had significantly lower Montreal Cognitive Assessment scores than those without HF (17.6±6.2 and 18.9±5.8 versus 19.9±6.0, P <0.001). The prevalence of moderate to severe cognitive impairment was highest in HF with reduced EF (43.3%), followed by HF with preserved EF (34.4%), no heart failure (28.6%), and HF with mildly reduced EF (23.4%) (adjusted trend P =0.032). Conclusions HF, independent of ejection fraction alone, is associated with cognitive impairment. Further studies should confirm these findings and evaluate the impact of interventions targeting EF and HF subtypes on cognitive outcomes.

BACKGROUND: Cerebral hemodynamic impairment in patients with asymptomatic high-grade (>70%) internal carotid artery (ICA) stenosis is associated with risk of stroke and cognitive decline, but correlations between the degree of stenosis and hemodynamic impairment are derived from small case series. Using baseline data from 242 participants in the CREST-H study (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis–Hemodynamics), we hypothesized that the degree of stenosis in the ICA would correlate with time-to-peak (TTP) delay in ipsilateral cerebral blood flow using MR/CT perfusion scans, adjusting for demographic and cardiovascular risk variables. METHODS: From all participants, ICAs were insonated using a 7 to 10 MHz probe for peak systolic velocity (PSV) and end diastolic velocity. Dynamic contrast perfusion imaging was standardized across 61 CREST-H sites, using standard sequential T2*-weighted perfusion imaging. CT perfusion used standard clinical protocols. TTP delay was calculated in the ipsilateral versus contralateral hemispheres. In cross-sectional analysis, linear regression was used to model TTP delay as the outcome variable and PSV, end diastolic velocity, and PSV ICA/common carotid artery ratio on the index and nonindex side as primary predictor variables in 6 separate models, adjusting for covariates, followed by automated backward elimination model reduction. RESULTS: Among 392 CREST-H participants, the 242 with complete data for all variables were included in the regression analysis (age, 70±7.6; 62% M). End diastolic velocity on the index side correlated with TTP delay (β=0.003, P =0.005). PSV had a similar correlation but did not reach significance (β=0.001, P =0.099), nor did ICA/common carotid artery ratio (β=0.003, P =0.126). Nonindex side PSV, end diastolic velocity, and ICA/common carotid artery ratio showed no correlation with TTP delay ( P =0.268, P =0.495, P =0.380, respectively). Circle of Willis completeness did not correlate with TTP. CONCLUSIONS: In this large cohort of patients with high-grade asymptomatic carotid stenosis, higher end-diastolic flow velocities correlated with greater TTP delays, supporting a definition of hemodynamically significant stenosis. Our findings have implications for the management of asymptomatic carotid stenosis, which will be tested in the CREST-H study. REGISTRATION: URL: https://www.clinicaltrials.gov ; Unique identifier: NCT03121209.