Nardi, Valentina

Background Peripheral microvascular endothelial dysfunction (PMED) has been linked to an increased risk of cardiovascular events, but there is a lack of information characterizing the predictive value of PMED for future risk of ischemic stroke (IS). Methods and Results This retrospective observational cohort study enrolled 637 patients who underwent non‐invasive microvascular endothelial function assessment using reactive hyperemia peripheral arterial tonometry. Reactive hyperemia peripheral arterial tonometry index ≤2 was defined as PMED. Of 280 patients with PMED, 12 (4.3%) patients developed IS, compared with only 4 (1.1%) of 357 patients without PMED during a median follow‐up of 5.3 years. Patients with PMED had lower IS‐free survival compared with patients without PMED (log‐rank P =0.03). Cox proportional hazard ratio (HR) analyses showed that PMED predicted the incidence of IS, with a HR of 3.43, 95% CI, 1.10–10.63 ( P =0.03); adjusted HR of 3.70, 95% CI, 1.18–11.59 ( P =0.02) after adjusting for sex, smoking history, and atrial fibrillation; adjusted HR of 3.45, 95% CI, 1.11–10.72 ( P =0.03) after adjusting for CHA 2 DS 2 ‐VASc score; adjusted HR of 5.70, 95% CI, 1.40–23.29 ( P =0.02) after adjusting for revised Framingham Stroke Risk Score. Reactive hyperemia peripheral arterial tonometry index improved discrimination of risk for IS after adding reactive hyperemia peripheral arterial tonometry index to CHA 2 DS 2 ‐VASc score and revised Framingham Stroke Risk Score. Conclusions PMED was associated with a >3‐fold increased risk of IS. These findings underscore the concept of the systemic nature of endothelial dysfunction, which could act as a potential marker to predict future risk of IS.

Background: Serum uric acid is a marker of oxidative stress, and may serve as a marker of adverse cardiovascular events and outcomes including cardiovascular death, hospitalization and myocardial infarction. We aimed to determine whether uric acid predicts cardiovascular events and death in patients undergoing carotid endarterectomy (CEA). Methods: We enrolled 327 patients undergoing CEA between February 2002 and June 2017 who had complete laboratory work up at baseline. Patients were followed through the electronic chart as well as via regular nursing follow-up for a median of 10.9 years (IQR 7.3, 13.4). There were a total of 67 adverse cardiovascular events during follow-up. Results: Baseline serum uric acid levels were significantly higher in patients who developed cardiovascular events during the follow-up period vs. those that did not [6.87 + 2.29 vs. 6.39 + 1.61); p=0.047). Baseline serum uric was independently associated with cardiovascular events when adjusting for age, creatinine, diabetes mellitus, and hyperlipidemia (L-R 4.0, p=0.04)(Figure 1). Sex stratified analysis showed that serum uric acid was also an independent predictor of both cardiovascular events and death in men, not women undergoing after adjustment for confounders including age, cholesterol, systolic blood pressure and glucose (LR 4.97; p=0.03). Discussion: Higher uric acid levels are associated with cardiovascular events and death after CEA. Further investigation is necessary to determine the role of uric acid as a modifiable risk factor in these patients.

Background: Uric acid is a known risk factor for atherosclerosis. We aimed to determine whether baseline uric acid levels predict plaque stability on presentation and future cerebrovascular events (CVA) in patients undergoing carotid endarterectomy (CEA). Methods: We analyzed 317 patients who underwent CEA between 2/2002 and 6/2017. Patients were stratified according to plaque stability as unstable or stable --those who presented with a history of > 1 neurologic event were “unstable” and those with no history of CVA were classified as stable. All patients underwent comprehensive baseline laboratory testing at baseline prior to CEA and then were followed by a nurse coordinator and through the medical record for the development of cerebrovascular events including stroke and transient ischemic attack for a median of 10.9 years (IQR 7.3, 13.4). Results: Baseline uric acid was significantly higher in patients presenting with unstable plaque vs. stable plaque(6.5 (IQR 5.6, 7.9) vs. 5.8(IQR 4.8,6.6); p<0.001), and was an independent predictor of plaque stability when adjusting for potential confounders including glucose, BMI, hsCRP, cholesterol, and systolic blood pressure (L-R 6.9, p=0.0096). There were a total of 58 CVA during follow-up, and baseline uric acid was higher among patients who developed CVA vs those without CVA [(6.9 + 2.1) mg/dL vs. (6.4 + 1.7) mg/dL; p=0.037]. After adjusting for diabetes, cholesterol, systolic blood pressure, smoking , age, aspirin, and creatinine, uric acid and cholesterol were both independent predictors of stroke in this population [uric acid: (LR 4.84, p=0.03); cholesterol: (L-R 11.8, p=0.0006)]. Discussion: While cholesterol has been associated with poor outcomes in patients with vascular disease, our data suggest that uric acid may be a novel risk factor for stroke in patients undergoing CEA. Further investigation is necessary to understand the therapeutic potential of reducing uric acid levels in these patients and the potential benefit of reducing overall cerebrovascular risk.

Background: High sensitivity C-reactive protein is a risk factor atherosclerosis and plaque rupture. We aimed to determine the role of high-sensitivity C reactive protein in predicting future cerebrovascular events (CVA), including stroke and transient ischemic attack, in patients undergoing routine carotid endarterectomy (CEA). Methods: A total of 251 patients underwent routine CEA without any history of stroke. At baseline prior to CEA, patients underwent routine laboratory testing, including testing for novel biomarkers including hs-CRP. Patients were followed for a median of 10.9 years (IQR 7.3, 13.4) for the development of CVA with regular nursing follow-up and/or chart review. Results: Of 251 patients enrolled in the study, 19 patients without prior CVA subsequently developed CVA during follow-up. In univariate analysis, baseline hsCRP was significantly higher in patients who developed CVA during follow-up vs. those that did not (8.1 (IQR 2.2, 46.3) mg/L vs. 3.85(0.9, 11.75) mg/L; p=0.0054)(Figure 1). After adjusting for confounders including age. diabetes mellitus, cholesterol, systolic blood pressure, history of smoking, aspirin use and duration of follow-up, log hsCRP was an independent predictor of CVA during follow-up after CEA (L-R 9.9; p=0.0016). Discussion: Hs-CRP appears to be a risk factor for CVA during follow-up after CEA. Further investigation is necessary to determine the role of risk modification in these patients and the therapeutic potential of reducing inflammation in this population.