Altered left atrial metrics in patients with cryptogenic stroke: A systematic review and meta-analysis

BACKGROUND

There is no defined cause for cryptogenic stroke/embolic stroke of undetermined source (CS-ESUS). As atrial fibrillation (AF) develops in a significant proportion of these patients, it has been suggested that left atrial (LA) myopathy may predispose to CS-ESUS. We investigated alterations in echocardiographic measures of LA size and function in patients with CS-ESUS.

METHODS

A systematic literature review and meta-analysis was performed. PubMed, EMBASE, Cochrane Library, Web of Science and SCOPUS were searched for articles published between 1 January 1990 and 10 February 2023. All observational studies of adult CS-ESUS patients with LA volume or function measurements performed by transthoracic echocardiogram were included. Individual random effects meta-analyses were performed on LA measurements in the CS-ESUS patients using subgroup analysis of comparator groups.

RESULTS

We included 29 articles with 3927 CS-ESUS patients. Analysis of weighted mean differences showed CS-ESUS patients had altered LA structure and function parameters, with a larger maximum indexed LA volume, reduced LA emptying fraction and/or LA reservoir strain, compared to healthy controls and noncardioembolic stroke patients. Conversely, CS-ESUS patients had a smaller left atrium with better function, compared to cardioembolic stroke patients and CS-ESUS patients who subsequently developed atrial fibrillation.

CONCLUSIONS

LA volume and function are altered in CS-ESUS patients compared to healthy controls and other stroke aetiologies. An underlying atrial myopathy in a subset of CS-ESUS patients may be involved in both thrombogenesis and dysrhythmia (specifically AF). While LA functional assessment is not currently recommended following stroke, it may offer an opportunity for recurrent stroke risk stratification.

Statin treatment and outcomes after embolic stroke of undetermined source

The association of low-density lipoprotein cholesterol lowering with outcomes in embolic stroke of undetermined source (ESUS) patients is unclear. In these patients we aimed to assess the effect of statin on stroke recurrence, major adverse cardiovascular events (MACE) and death rates. Consecutive ESUS patients in the Athens Stroke Registry were prospectively followed-up to 10 years for stroke recurrence, MACE, and death. The Nelson-Aalen estimator was used to estimate the cumulative probability by statin allocation at discharge and cox-regression analyses to investigate whether statin at discharge was a predictor of outcomes. Among 264 ESUS patients who were discharged and followed for 4 years, 89 (33.7%) were treated with statin at discharge. Patients who were discharged on statin had lower rates of stroke recurrence (3.58 vs. 7.23/100 patient-years, HR: 0.48; 95% CI 0.26-0.90), MACE (4.98 vs. 9.89/100 patient-years, HR: 0.49; 95% CI 0.29-0.85), and death (3.93 vs. 8.21/100 patient-years, HR: 0.50; 95% CI: 0.28-0.89). In the multivariate analysis, statin treatment at discharge was an independent predictor of stroke recurrence (adjusted HR: 0.48; 95% CI 0.26-0.91), MACE (adjusted HR: 0.48; 95% CI 0.28-0.82), and death (adjusted HR: 0.50; 95% CI 0.27-0.93). Patients with ESUS discharged on statins have lower rates of stroke recurrence, MACE, and death compared to those not receiving statin therapy.

Carotid web leads to new thrombus formation: computational fluid dynamic analysis coupled with histological evidence

Carotid web has been recognized as a rare cause of ischemic stroke with high recurrence rate. We describe a 48-year-old woman with carotid web who developed embolic stroke. We obtained a fresh thrombus from the internal carotid artery when carotid endarterectomy was performed. A preoperative computational fluid dynamics (CFD) study showed stagnation of blood around the web structure as well as the low wall shear stress. The rheological analysis newly disclosed mechanisms of thrombus formation related to the carotid web. CFD study in the carotid web may determine indication and timing of surgical interventions with further accumulation of clinical evidence.

Immune-Inflammatory, Metabolic, Oxidative, and Nitrosative Stress Biomarkers Predict Acute Ischemic Stroke and Short-Term Outcome

Immune-inflammatory, metabolic, oxidative, and nitrosative stress (IMO&NS) pathways and, consequently, neurotoxicity are involved in acute ischemic stroke (IS). The simultaneous assessment of multiple IMO&NS biomarkers may be useful to predict IS and its prognosis. The aim of this study was to identify the IMO&NS biomarkers, which predict short-term IS outcome. The study included 176 IS patients and 176 healthy controls. Modified Rankin scale (mRS) was applied within 8 h after IS (baseline) and 3 months later (endpoint). Blood samples were obtained within 24 h after hospital admission. IS was associated with increased white blood cell (WBC) counts, high sensitivity C-reactive protein (hsCRP), interleukin (IL-6), lipid hydroperoxides (LOOHs), nitric oxide metabolites (NOx), homocysteine, ferritin, erythrocyte sedimentation rate (ESR), glucose, insulin, and lowered iron, 25-hydroxyvitamin D [25(OH)D], total cholesterol, and high-density lipoprotein (HDL) cholesterol. We found that 89.4% of the IS patients may be correctly classified using the cumulative effects of male sex, systolic blood pressure (SBP), glucose, NOx, LOOH, 25(OH)D, IL-6, and WBC with sensitivity of 86.2% and specificity of 93.0%. Moreover, increased baseline disability (mRS ≥ 3) was associated with increased ferritin, IL-6, hsCRP, WBC, ESR, and glucose. We found that 25.0% of the variance in the 3-month endpoint (mRS) was explained by the regression on glucose, ESR, age (all positively), and HDL-cholesterol, and 25(OH)D (both negatively). These results show that the cumulative effects of IMO&NS biomarkers are associated with IS and predict a poor outcome at 3-month follow-up.