Objective:To investigate the association between abnormal left atrial appendage function and thrombotic events in patients with non-valvular atrial fibrillation, and the independent risk factors affecting left atrial appendage function.Methods:Patients with non-valvular atrial fibrillation, who visited the Atrial Fibrillation Center of the First Affiliated Hospital of Xinjiang Medical University from June 1, 2019 to June 1, 2021, were selected. According to left atrial appendage flow velocity (LAAFV), they were divided into normal left atrial appendage function group (297 patients with LAAFV ≥ 40 cm/s) and abnormal left atrial appendage function group (85 patients with LAAFV<40 cm/s). Baseline data and transesophageal echocardiography images were collected from all the patients. The occurrence of thrombotic events was recorded. Univariate and multivariate unconditional logistic regression analyses were conducted to investigate the correlation between abnormal left atrial appendage function and the occurrence of thrombotic events.Results:There were significant differences in gender, type of atrial fibrillation, CHA 2DS 2-VASc score, anticoagulant therapy, total cholesterol, low-density lipoprotein cholesterol, international normalized ratio (INR), left atrial diameter, proportion of patients with right atrial enlargement, left ventricular ejection fraction, inner diameter, sum of inner diameter, depth, and sum of depth of all angles of the left atrial appendage, and incidence of thrombotic events between the two groups (all P<0.05). After adjusting for confounders, multivariate unconditional logistic regression analyses showed that abnormal left atrial appendage function was closely associated with thrombotic events (β=1.168 P=0.002), and left atrial diameter ( OR=1.084, 95% CI 1.019-1.153, P=0.011) and persistent atrial fibrillation ( OR=2.323, 95% CI 1.226-4.403, P=0.010) were independent risk factors affecting left atrial appendage function. Conclusions:Abnormal left atrial appendage function is closely associated with thrombosis. The left atrial diameter and persistent atrial fibrillation were independent risk factors affecting left atrial appendage function.

Objectives:This study aims to explore the effects of pioglitazone on the attenuation of ventricular arrhythmias(VAs)induced by β1-adrenergic receptor autoantibodies(β1AAb)and its potential mechanisms. Methods:48 SD rats were uniformly randomly divided into four groups using number table:control group received vehicle injection,β1AAb group received back multi-point injection of β1AR-ECLⅡ antigen peptide with adjuvant,2 mg/(kg·time),pioglitazone group received pioglitazone gavage for 2 weeks after 8 weeks of immunization,4 mg/(kg·d),and GW9662 group received pioglitazone+GW9662 intraperitoneal injection for 2 weeks after 8 weeks of immunization,1 mg/(kg·d).Powerlab recorded electrocardiograms and blood collection every 2 weeks.Baseline and week 10 echocardiography were recorded,followed by electrophysiology,histopathology,immunohistochemical staining,and electron microscopy examination after 10 weeks. Results:Compared to control group,β1AAb group showed a higher incidence of ventricular arrhythmias,shorter ventricular effective refractory period(VERP),longer action-recovery interval(ARI),lower left ventricular ejection fraction(LVEF)and left ventricular fractional shortening(LVFS),lower positive staining area ratio of glucose transporter 1(GLUT1)and carnitine palmitoyltransferase 1a(CPT1a),all P＜0.05.Mitochondrial morphology abnormalities and network damage were also significantly observed(P＜0.05).In contrast to β1AAb group,pioglitazone group showed a reduced incidence of ventricular arrhythmias,prolonged VERP,shortened ARI,recovered LVEF and LVFS,increased the positive staining area ratio of GLUT1 and CPT1a,all P＜0.05.Improvement was observed in mitochondrial morphology abnormalities and network damage(P＜0.05).Compared to pioglitazone group,GW9662 group exhibited a higher incidence of ventricular arrhythmias,shorter VERP,and longer ARI,lower LVEF and LVFS,lower positive staining area ratio of GLUT1 and CPT1a,all P＜0.05.Mitochondrial morphology abnormalities and network damage did not recover(P＜0.05). Conclusions:Pioglitazone can reduce VAs induced by β1AAb,improve ventricular electrical conduction and activation recovery time heterogeneity,and mitigate ventricular remodeling caused by β1AAb at the tissue pathology level,accompanied by upregulation of ventricular cardiomyocyte glucose and lipid transport channel proteins and repair of damaged mitochondrial networks.