Association between the preprocedural serum potassium level and atrial fibrillation recurrence after catheter ablation.

BACKGROUND: The association between serum potassium and atrial fibrillation (AF) recurrence after catheter ablation remains unclear. OBJECTIVE: The purpose of this study was to investigate whether preprocedural serum potassium influences AF recurrence in patients who underwent catheter ablation. METHODS: We used data of patients with AF who underwent de novo catheter ablation from the prospective Chinese Atrial Fibrillation Registry Study. Patients with prior ablation and without baseline serum potassium were excluded. The primary outcome was 1-year AF recurrence after a 3-month blanking period from the ablation procedure. Restricted cubic spline and Cox proportional models were used to compare outcomes across serum potassium categories. RESULTS: A total of 4838 patients with AF who underwent de novo catheter ablation was enrolled. At 1 year, AF recurrence occurred in 1347 patients (27.8%). The relationship between preprocedural serum potassium and 1-year AF recurrence after ablation presented as U shape (P for nonlinear = .048). Compared with the group of serum potassium within 4.41-4.60 mmol/L, the risk of AF recurrence increased significantly in the lowest serum potassium group (≤4.00 mmol/L) after multivariate analysis (hazard ratio [HR] 1.26; 95% confidence interval 1.06-1.51; P = .010). Other categories with lower or higher serum potassium levels including 4.01-4.20 mmol/L (HR 1.18), 4.21-4.40 mmol/L (HR 1.16), 4.61-4.80 mmol/L (HR 1.07), and ≥4.81 mmol/L (HR 1.11) showed nonsignificant higher recurrence risk. CONCLUSION: The relationship between preprocedural potassium and AF recurrence was U shaped, with an optimal potassium range (4.41-4.60 mmol/L). Lower potassium level is associated with increased AF recurrence risk after catheter ablation.

Sensory Nerve Regulation via H3K27 Demethylation Revealed in Akermanite Composite Microspheres Repairing Maxillofacial Bone Defect.

Maxillofacial bone defects exhibit intricate anatomy and irregular morphology, presenting challenges for effective treatment. This study aimed to address these challenges by developing an injectable bioactive composite microsphere, termed D-P-Ak (polydopamine-PLGA-akermanite), designed to fit within the defect site while minimizing injury. The D-P-Ak microspheres biodegraded gradually, releasing calcium, magnesium, and silicon ions, which, notably, not only directly stimulated the osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs) but also activated sensory nerve cells to secrete calcitonin gene-related peptide (CGRP), a key factor in bone repair. Moreover, the released CGRP enhanced the osteogenic differentiation of BMSCs through epigenetic methylation modification. Specifically, inhibition of EZH2 and enhancement of KDM6A reduced the trimethylation level of histone 3 at lysine 27 (H3K27), thereby activating the transcription of osteogenic genes such as Runx2 and Osx. The efficacy of the bioactive microspheres in bone repair is validated in a rat mandibular defect model, demonstrating that peripheral nerve response facilitates bone regeneration through epigenetic modification. These findings illuminated a novel strategy for constructing neuroactive osteo-inductive biomaterials with potential for further clinical applications.

Small Left Ventricle in Patients With Atrial Fibrillation Is Associated With Increased Cardiovascular Risk.

BACKGROUND: It is still unclear whether small left ventricle (LV) is an adverse structural prognostic feature in patients with atrial fibrillation (AF). OBJECTIVES: The purpose of this study was to evaluate the association between small LV and risk of cardiovascular events in AF population. METHODS: From the China-AF registry, 7,764 patients with AF were enrolled and divided into groups with normal, small, and large LV size based on left ventricular end-diastolic dimension (LVEDD) measurement per the American Society of Echocardiography references. Cox models were used to assess the association between LV size or LVEDD with composite cardiovascular events (cardiovascular death, ischemic stroke or systemic embolism, or major bleeding). RESULTS: There were 308 (4.0%) participants assessed with small LV who were older, with lower body mass and blood pressure, and fewer comorbidities, and 429 (5.5%) were identified with large LV. Compared with the normal LV group, small LV and large LV were significantly associated with higher incidence of composite cardiovascular events (adjusted HR [aHR]: 1.54 [95% CI: 1.07-2.20] for small LV; aHR: 1.36 [95% CI: 1.02-1.81] for large LV) and cardiovascular death (aHR: 1.94 [95% CI: 1.14-3.28] for small LV; aHR: 1.83 [95% CI: 1.24-2.69] for large LV). Small LV was also associated with increased risk of major bleeding [aHR: 2.21 [95% CI: 1.01-4.86]). A U-shaped relationship between LVEDD and composite cardiovascular events was identified (Pnonlinear < 0.001). CONCLUSIONS: In a prospective AF cohort, small LV was independently associated with an increased risk of cardiovascular events, which needed consideration in risk stratification and management for patients with AF. (ChiCTR-OCH-13003729).

Advances in neuronal reprogramming for neurodegenerative diseases: Strategies, controversies, and opportunities.

Neuronal death is often observed in central nervous system injuries and neurodegenerative diseases. The mammalian central nervous system manifests limited neuronal regeneration capabilities, and traditional cell therapies are limited in their potential applications due to finite cell sources and immune rejection. Neuronal reprogramming has emerged as a novel technology, in which non-neuronal cells (e.g. glial cells) are transdifferentiated into mature neurons. This process results in relatively minimal immune rejection. The present review discuss the latest progress in this cutting-edge field, including starter cell selection, innovative technical strategies and methods of neuronal reprogramming for neurodegenerative diseases, as well as the potential problems and controversies. The further development of neuronal reprogramming technology may pave the way for novel therapeutic strategies in the treatment of neurodegenerative diseases.

Evaluation of an algorithm-guided photoplethysmography for atrial fibrillation burden using a smartwatch.

BACKGROUND: Wearable devices based on the PPG algorithm can detect atrial fibrillation (AF) effectively. However, further investigation of its application on long-term, continuous monitoring of AF burden is warranted. METHOD: The performance of a smartwatch with continuous photoplethysmography (PPG) and PPG-based algorithms for AF burden estimation was evaluated in a prospective study enrolling AF patients admitted to Beijing Anzhen Hospital for catheter ablation from September to November 2022. A continuous Electrocardiograph patch (ECG) was used as the reference device to validate algorithm performance for AF detection in 30-s intervals. RESULTS: A total of 578669 non-overlapping 30-s intervals for PPG and ECG each from 245 eligible patients were generated. An interval-level sensitivity of PPG was 96.3% (95% CI 96.2%-96.4%), and specificity was 99.5% (95% CI 99.5%-99.6%) for the estimation of AF burden. AF burden estimation by PPG was highly correlated with AF burden calculated by ECG via Pearson correlation coefficient (R2 = 0.996) with a mean difference of -0.59 (95% limits of agreement, -7.9% to 6.7%). The subgroup study showed the robust performance of the algorithm in different subgroups, including heart rate and different hours of the day. CONCLUSION: Our results showed the smartwatch with an algorithm-based PPG monitor has good accuracy and stability in continuously monitoring AF burden compared with ECG patch monitors, indicating its potential for diagnosing and managing AF.

Orthostatic blood pressure changes do not influence cognitive outcomes following intensive blood pressure control.

BACKGROUND: Effects of intensive blood pressure (BP) control on cognitive outcomes in patients with excess orthostatic BP changes are unclear. We aimed to evaluate whether orthostatic BP changes modified the effects of BP intervention on cognitive impairment. METHODS: We analyzed 8547 participants from the Systolic Blood Pressure Intervention Trial Memory and cognition IN Decreased Hypertension. Associations between orthostatic BP changes and incident cognitive outcomes were evaluated by restricted cubic spline curves based on Cox models. The interactions between orthostatic BP changes and intensive BP intervention were assessed. RESULTS: The U-shaped associations were observed between baseline orthostatic systolic BP changes and cognitive outcomes. However, there were insignificant interactions between either change in orthostatic systolic BP (P for interaction = 0.81) or diastolic BP (P for interaction = 0.32) and intensive BP intervention for the composite outcome of probable dementia or mild cognitive impairment (MCI). The hazard ratio of intensive versus standard target for the composite cognitive outcome was 0.82 (95% CI 0.50-1.35) in those with an orthostatic systolic BP reduction of >20 mmHg and 0.41 (95% CI 0.21-0.80) in those with an orthostatic systolic BP increase of >20 mmHg. Results were similar for probable dementia and MCI. The annual changes in global cerebral blood flow (P for interaction = 0.86) consistently favored intensive BP treatment across orthostatic systolic BP changes. CONCLUSION: Intensive BP control did not have a deteriorating effect on cognitive outcomes among hypertensive patients experiencing significant postural BP changes.