Non-insulin-based insulin resistance indexes in predicting atrial fibrillation recurrence following ablation: a retrospective study.

BACKGROUND: Insulin resistance (IR) is involved in the pathophysiological processes of arrhythmias. Increasing evidence suggests triglyceride and glucose (TyG) index, metabolic score for insulin resistance (METS-IR), triglyceride glucose-body mass index (TyG-BMI), and triglyceride to high-density lipoprotein cholesterol (TG/HDL-C) ratio are simple and reliable surrogates for IR. Although they have been associated with atrial fibrillation (AF), evidence supporting this is limited. Here, this is the first study to investigate the association between TyG-BMI index and AF recurrence following radiofrequency catheter ablation (RFCA). The performance of the four non-insulin-based IR indexes in predicting AF recurrence after ablation was explored. METHODS: A total of 2242 AF patients who underwent a de novo RFCA between June 2018 to January 2022 at two hospitals in China were included in this retrospective study. The predictive values of IR indexes for AF recurrence after ablation were assessed. RESULTS: During 1-year follow-up, 31.7% of patients experienced AF recurrence. The multivariable analysis revealed that TyG index, METS-IR, and TyG-BMI index were independent risk factors for AF recurrence. Restricted cubic spline analysis revealed a connection between METS-IR, TyG-BMI index, and AF recurrence (P < 0.001). Furthermore, incorporating the METS-IR or TyG-BMI index to the basic risk model with fully adjusted factors considerably enhanced the forecast of AF recurrence, as demonstrated by the C-statistic, continuous net reclassification improvement, and integrated discrimination improvement. CONCLUSIONS: TyG index, METS-IR, and TyG-BMI index were independently associated with AF recurrence following ablation. Among the four non-insulin-based IR indexes, TyG-BMI had the highest predictive value, followed by METS-IR.

A cohort study of self-perception of ageing and all-cause mortality among older adults in China: a multiple mediators analysis.

BACKGROUND: Positive self-perception of aging (SPA) is a well-known predictor of longevity, while how and to what extent SPA is linked with all-cause mortality among older adults is still unclear. This study aims to elucidate the relationship between positive SPA and all-cause mortality and its potential mediators among Chinese older adults. METHODS: This is a 20-year dynamic cohort study conducted among 22,957 older adults aged ≥ 65 years old from a nationally representative sample. Positive SPA was measured using a validated 7-item scale. Potential mediators including health behaviors and social participation were collected using a self-reported questionnaire. Cox proportional hazards regression models were conducted to examine the association between positive SPA and all-cause mortality. A mediation analysis was conducted to determine whether health behaviors and social participation mediated the association between SPA and all-cause mortality. RESULTS: Throughout follow-up (median [interquartile range], 46 [21-84] months), all-cause mortality was 87.4%. Compared with older adults with the lowest quartile positive SPA, hazard ratio(HR) of all-cause mortality among older adults with the second, third, and fourth quartile of positive SPA was 0.96(95%CI:0.93-1.00), 0.93(95%CI:0.90-0.99), and 0.92(95%CI:0.87-0.96) respectively after controlling for all potential mediators and covariates. The mediation analysis showed that regular daily vegetable intake, physical activity, and high social participation explained 41.1-48.5% of the variance in the association between positive SPA and all-cause mortality. CONCLUSIONS: In this cohort study, we found that high positive SPA was associated with decreased all-cause mortality directly, and indirectly through healthy lifestyle behaviors and social participation. These findings suggest that interventions targeted at promoting or maintaining positive SPA may contribute to healthy ageing among older adults in China.

Independent Association between Epicardial Adipose Tissue Volume and Recurrence of Idiopathic Ventricular Tachycardia after Ablation.

Background: Epicardial adipose tissue (EAT) thickness is an independent predictor for the recurrence of premature ventricular beats after ablation. However, it is unclear whether EAT volume is associated with the recurrence of idiopathic ventricular tachycardia (IVT) following ablation. This study sought to investigate the association between EAT volume and IVT recurrence following radiofrequency ablation for IVT patients. Methods: This retrospective study included 69 IVT patients undergoing computed tomography examination before ablation who underwent their first catheter ablation between 2017 and 2021. The predictive value of EAT volume for IVT recurrence following ablation was assessed. Results: During the follow-up period (median: 540 days; range: 253-929 days), 26.1% (18/69) of the patients experienced IVT recurrence. The cut-off point of EAT volume for predicting IVT recurrence was 160.30 mL, and the area under the curve (AUC) was 0.751 (95% confidence interval (CI): 0.615-0.887) by the receiver operating characteristic curve. Kaplan-Meier analysis showed that patients with larger EAT volumes had higher cumulative rates of IVT recurrence. Multivariable analysis also revealed that EAT volume (per 10 mL increase; hazard ratio (HR): 1.16, 95% CI: 1.03-1.32, p = 0.018) was independently associated with IVT recurrence. Furthermore, patients with an epicardial site of IVT had a significantly larger EAT volume than IVT patients with non-epicardial origins. Conclusions: A larger EAT volume may be associated with IVT recurrence after catheter ablation. EAT volume may be helpful for risk stratification in patients undergoing IVT ablation.

High-fructose corn syrup aggravates colitis via microbiota dysbiosis-mediated Th17/Treg imbalance.

Dietary fructose is widely used in beverages, processed foods, and Western diets as food additives, and is closely related to the increased prevalence of multiple diseases, including inflammatory bowel disease (IBD). However, the detailed mechanism by which high fructose disrupts intestinal homeostasis remains elusive. The present study showed that high-fructose corn syrup (HFCS) administration exacerbated intestinal inflammation and deteriorated barrier integrity. Several in vivo experimental models were utilized to verify the importance of gut microbiota and immune cells in HFCS-mediated dextran sulfate sodium (DSS)-induced colitis. In addition, untargeted metabolomics analysis revealed the imbalance between primary bile acids (PBAs) and secondary bile acids (SBAs) in feces. Hence, high fructose was speculated to modulate gut microbiota community and reduced the relative abundance of Clostridium and Clostridium scindens at genus and species level respectively, followed by a decrease in SBAs, especially isoalloLCA, thereby affecting Th17/Treg cells equilibrium and promoting intestinal inflammation. These findings provide novel insights into the crosstalk between gut flora, bile acids, and mucosal immunity, and highlight potential strategies for precise treatment of IBD.

Relationship Between Epicardial Adipose Tissue Volume and Recurrence After Ablation in Premature Ventricular Complexes.

BACKGROUND: Epicardial adipose tissue (EAT) is recognized as a clinical diagnostic marker for cardiometabolic disease. Thicker EAT may be associated with recurrence of ventricular tachycardia after ablation. The association between EAT volume and recurrence of premature ventricular complexes (PVC) following ablation has not been clarified. We investigated the association between EAT volume and PVC recurrence following radiofrequency catheter ablation.Methods and Results: This retrospective study included 401 patients with PVC undergoing catheter ablation with preprocedural non-contrast computed tomography between 2017 and 2022. The impact of EAT volume in predicting PVC recurrence after ablation was analyzed. The mean (±SD) age of patients was 50.2±13.3 years. Multivariable Cox analysis revealed that a large EAT volume was an independent predictor of PVC recurrence after ablation during a median follow-up of 16.3 months. Kaplan-Meier analysis showed a difference in postablation PVC recurrence between the 2 groups dichotomized around the EAT volume cut-off. The risk of recurrence increased with increasing EAT volume according to restricted cubic spline regression. Furthermore, PVC originating from epicardial locations had larger EAT volumes than those originating from the right ventricular outflow tract. CONCLUSIONS: A large EAT volume was independently associated with PVC recurrence following ablation. Patients with PVC originating from epicardial sites had large EAT volumes. EAT volume may help stratify patients according to their risk of PVC recurrence after ablation.

Effect of Insulin Resistance on Recurrence after Radiofrequency Catheter Ablation in Patients with Atrial Fibrillation.

BACKGROUND: Whether there are many risk factors for recurrence of atrial fibrillation (AF) after ablation is unclear. The aim of this study was to investigate the relationship between insulin resistance (IR) and AF recurrence in patients without diabetes who underwent catheter ablation. METHODS: This retrospective study included patients who underwent AF ablation between 2018 and 2019 at the First Affiliated Hospital of Zhengzhou University. Homeostasis model assessment of insulin resistance (HOMA-IR) was calculated, and a value of ≥2.69 was defined as IR. The patients were divided into two groups (group 1 HOMA-IR < 2.69, n = 163; group 2 HOMA-IR ≥ 2.69, n = 69). AF recurrence was defined as the occurrence of atrial arrhythmias of more than 30 s after the first 3 months. Univariate and multivariable Cox regression models were used to analyse the risk of AF recurrence. RESULTS: Overall, 232 patients were enrolled (mean age, 59.9 ± 10.2 years old; female, 37.5%; paroxysmal AF, 71.6%). We found that dyslipidaemia, antiarrhythmic drug use, fasting blood glucose and fasting insulin were significantly higher in the IR group (P < 0.05). During the follow-up 1 year after ablation, 62 (26.7%) patients experienced AF recurrence. After adjusting for traditional risk factors, multivariable analysis showed that the HOMA-IR value (HR 1.259, 95% CI 1.086-1.460, P = 0.002) and left atrial diameter (LAD; HR 1.043, 95% CI 1.005-1.083, P = 0.026) were independently associated with AF recurrence. CONCLUSIONS: The present results provide evidence that IR patients are more likely to experience AF recurrence. Improving IR status may be a potential target for reducing the postoperative recurrence rate.

Impact of carotid atherosclerosis on arrhythmia recurrence following atrial fibrillation catheter ablation.

BACKGROUND: It remains unclear whether carotid atherosclerosis (CAS) increases the atrial fibrillation (AF) recurrence rate after ablation. The aim was to assess the association between CAS, defined as carotid intima-media thickness (CIMT) ≥1 mm and or presence of carotid plaques, and AF recurrence rate after ablation. METHODS: We retrospectively collected patients who underwent carotid ultrasonography and AF ablation at the First Affiliated Hospital of Zhengzhou University. The AF recurrence was defined as documented atrial arrhythmias over 30 s on ECG or 24-h Holter monitoring after the first three months blanking period. Cox regression models were used to analyze the risk of AF recurrence. RESULTS: Overall, 385 patients were analyzed (mean age, 60.58±10.98 years old; female, 41.30%; persistent AF, 47.27%). After a follow-up of 1 year, 138 (35.84%) patients experienced recurrence, Kaplan-Meier analysis showed that patients with the presence of carotid plaques, CIMT ≥1 mm, and CAS had a higher risk of recurrence compared with the absence (all log-rank p < .05). In multivariate Cox regression analysis, CAS (HR 2.159, ±95% CI 1.320-3.532, p = .002), carotid plaque (HR 1.815, ±95%CI 1.160-2.841, p = .009), and CIMT ≥1 mm (HR 1.696, ±95%CI 1.192-2.413, p = .003) were independently associated with a higher risk of recurrence. In subgroup analysis, the association of CAS, carotid plaque, and AF recurrence rate was weaker in men than women. CONCLUSION: Carotid atherosclerosis, CIMT ≥1 mm, and carotid plaque were significantly associated with a higher AF recurrence rate after radiofrequency catheter ablation. They were all risk factors for the recurrence of AF.

Salidroside alleviates ulcerative colitis via inhibiting macrophage pyroptosis and repairing the dysbacteriosis-associated Th17/Treg imbalance.

Ulcerative colitis (UC) is a chronic inflammatory bowel disease characterized by flora disequilibrium and mucosal immunity disorder. Here, we report that salidroside effectively restricts experimental colitis from two aspects of intestinal macrophage pyroptosis and dysbacteriosis-derived colonic Th17/Treg imbalance. In innate immunity, the upregulated TREM1 and pyroptosis-related proteins in inflamed colons were inhibited by salidroside administration and further experiments in vitro showed that salidroside suppressed LPS/ATP-induced bone marrow-derived macrophages (BMDMs) pyroptosis evident by the decline of LDH and IL-1ß release as well as the protein level of NLRP3, caspase-1, and GSDMD p30. Moreover, the TREM1 inhibitor weakened the effect of salidroside on BMDMs pyroptosis, whereas salidroside still could downregulate TREM1 when NLRP3 was inhibited. In adaptive immunity, salidroside improved the gut microflora diversity and Th17/Treg ratio in DSS-induced mice, especially promoting the abundance of Firmicutes. Clearance of the gut flora blocked the benefit of salidroside on colonic inflammation and Th17/Treg adaptive immunity, but transplanting salidroside-treated foecal bacterium into flora-depleted wild mice reproduced the resistance of salidroside to gut inflammation. Taken together, our data demonstrated that salidroside protected experimental colitis via skewing macrophage pyroptosis and Th17/Treg balance, indicating its potential effect on UC and other immune disorders.

Effect of Dapagliflozin on the Outcome of Radiofrequency Catheter Ablation in Patients with Type 2 Diabetes Mellitus and Atrial Fibrillation.

INTRODUCTION: Dapagliflozin, one of the sodium-glucose cotransporter-2 inhibitors, has been widely used for the treatment of type 2 diabetes mellitus (T2DM) and heart failure. In this study, we sought to determine the impact of dapagliflozin on the outcome of radiofrequency catheter ablation (RFCA) for patients with T2DM and atrial fibrillation (AF). METHODS: This retrospective study included patients who underwent AF ablation between January 2019 to February 2021 at the First Affiliated Hospital of Zhengzhou University. All patients had a history of T2DM and were divided into the dapagliflozin group (n = 79) and the control group (n = 247) according to whether the patients were treated with dapagliflozin after ablation. The definition of AF recurrence was documented atrial arrhythmias over 30 s after a 1-month blanking period. Cox regression models were used to analyze the risk of AF recurrence. RESULTS: Overall, 326 patients were analyzed (mean age, 63.7±10.0 years old; male, 58.9%; paroxysmal AF, 52.8%; recurrence rate, 40.8%). We found that hemoglobin A1c before ablation was higher in the dapagliflozin group than in the control group (7.7±1.4 vs. 7.3±1.2, P = 0.007). After a mean follow-up of 15.5±8.9 months, the dapagliflozin group had a lower recurrence rate than the control group (27.8% vs. 44.9%, P = 0.007). Treatment with dapagliflozin (HR 0.614, ±95%CI 0.387-0.974, P = 0.038) was associated with a lower risk of recurrence of atrial arrhythmias (ATa) after ablation in multivariable Cox regression models that adjusted for duration of AF, BMI, AF type, left atrial diameter (LAD), and eGFR. The Cox regression model that incorporated hemoglobin A1c and other antidiabetic agents also demonstrated a similar reduction in the risk of recurrent atrial arrhythmias with dapagliflozin treatment (HR 0.611, ±95% CI 0.379-0.985, P = 0.043). CONCLUSIONS: In patients with T2DM, treatment with dapagliflozin appears to be independently associated with a significant reduction in the risk of recurrent atrial arrhythmias after RFCA.

Amino acid-balanced diets improved DSS-induced colitis by alleviating inflammation and regulating gut microbiota.

PURPOSE: Inflammatory bowel disease (IBD) is a multifactorial chronic disease of the gastrointestinal tract. Dietary intervention in the treatment of IBD has gradually attracted more attention. In this study, amino acid-balanced diets (AABD) based on grains were developed and their influences on the regulation of IBD were investigated. METHODS: Dextran sodium sulfate (DSS)-induced acute colitis mice model was employed to evaluate the effects of AABD. Pathological symptoms, intestinal inflammation, gut barrier proteins and gut microbiota were determined after AABD intake. RESULTS: It was shown that AABD alleviated the symptoms of colitis by reducing the histological scores of mice colon, suppressing the expression of pro-inflammatory cytokines (IL-1ß, IL-6 and TNF-α) and upregulating the expression of tight junction proteins. Analysis of gut microbiota revealed that AABD altered the structure of gut microbiota by decreasing the abundance and richness of harmful bacteria induced by DSS (Escherichia-Shigella, Parasutterella, etc.) and increasing that of beneficial bacteria (Akkermansia, etc.). Correlation analysis indicated that the alterations of pro-inflammatory factors were related with the change of microbiota, suggesting that the inhibitory effects of AABD on inflammation might be due to its regulation gut microbiota. CONCLUSION: The AABD could efficiently mitigate colitis, and this study indicated that AABD could be applied as a promising dietary regulation strategy of IBD.

Result and technique consideration of radiofrequency catheter ablation of tachycardia in patients with dextrocardia.

BACKGROUND: Patients with tachycardia, in the context of pre-existing dextrocardia, could benefit from catheter ablation. However, anatomical complexities hinder effective conduct of this procedure. We aimed to retrospectively summarize the clinical characteristics and the safety and efficiency, and recommended the technique considerations. METHODS: Twenty-one cases from 19 patients with tachycardia and dextrocardia, who underwent catheter ablation between 2009 and 2021, were enrolled. All patients underwent echocardiography and computed tomography (CT) to confirm the anatomical malformations. Transseptal puncture was guided by fluoroscopy or intracardiac echocardiography when left atrial access was necessary and the ablation process was guided by three-dimensional (3D) mapping. RESULTS: Six cases exhibited situs solitus while nine cases exhibited situs inversus. Fourteen cases had atrial fibrillation, seven had atrial flutter, and two had atrioventricular reentrant tachycardia (AVRT); two cases had combined atrial fibrillation and atrial flutter. Acute success was achieved in 18 cases (85.7%, 18/21). The 3D mapping system was not employed in the three cases which failed. During long-term follow-up (20.71 ± 21.86 months), eight cases (72.7%, 8/11) of atrial fibrillation with dextrocardia successfully attained sinus rhythm. None of AVRT cases had recurrence. Half of the atrial flutter cases with dextrocardia, especially those with a history of surgical correction for cardiac malformations, underwent recurrence. One case had cardiac tamponade. CONCLUSIONS: Catheter ablation for tachycardia patients with dextrocardia is safe, efficient, and feasible. It is imperative to integrate echocardiography, cardiac computer tomography, and 3D mapping, and apply 3D reconstruction to facilitate the success of catheter ablation.

Sleep characteristic profiles and the correlation with spectrum of metabolic syndrome among older adult: a cross-sectional study.

BACKGROUND: Metabolic Syndrome (MetS) is a common health problem among older adults. Previous studies have revealed the relationship between sleep duration as well as global sleep status and MetS. OBJECTIVES: This study aims to examine the association between the specific sleep characteristic and MetS as well as MetS components among community-dwelling old adults. METHODS: This cross-sectional study included 1499 community residents aged ≥ 60 years. Sleep characteristics were assessed using the Pittsburgh Sleep Quality Index (PSQI) and bed/rise time of the residents. Logistic regression analysis and multiple linear regression analysis were used to examine the associations between sleep characteristics and MetS as well as MetS components. A generalized additive model was built to assess the smooth relationship between triglyceride (TG) levels and sleep duration. RESULTS: Of the 1499 participants, 449 (30.0%) had MetS, and 443 (29.6%) had poor sleep quality. The rise time was found to be associated with MetS (> 6:00 vs. 5:00 ~ 6:00: adjusted OR (95%) = 1.77 (1.17-2.69), P = 0.007). For the MetS components, a U-shaped relationship was first revealed for sleep duration and TG levels (EDF = 1.85, P < 0.001). Furthermore, significant associations also included the associations of subjective sleep quality and daytime dysfunction with hypertension, the associations of sleep efficiency and rise time with hyperglycemia, the associations of rise time with TG levels, and the association of bedtime with waist circumference. CONCLUSIONS: The different sleep characteristics were associated with different MetS components.

An isolated hypogonadotropic hypogonadism male with a novel de novoFGFR1 mutation fathered a normal son evidenced by prenatal genetic diagnosis.

Isolated hypogonadotropic hypogonadism (IHH) is a rare but treatable form of male infertility caused by congenital defect in gonadotropin-releasing hormone (GnRH) secretion or action. We report a Chinese IHH male with a novel FGFR1 mutation who successfully fathered a normal son. Targeted next-generation sequencing, bioinformatics analysis and Sanger sequencing were performed by using the DNA extracted from the pedigree. The patient was treated with gonadotropin and was able to impregnant his wife during the treatment. Amniocentesis was performed at the 18 weeks of gestation. A novel de novo pathogenic missense variant (c.980A>G, p.Asn327Ser) in exon 8 in FGFR1 gene (NM_001174067.1) was identified in the patient but not in his normal parents. This variant was also absent in the DNA obtained from the amniocentesis sample. His son has normal growth and development at the age of 2 years. This is the first case of prenatal genetic diagnosis based on the genetic testing of the IHH father by combining targeted next-generation and Sanger sequencing in IHH family. We extended the mutation spectrum of FGFR1 in IHH patients. Prenatal genetic diagnosis based on the results of genetic testing of the IHH patients may be helpful in the genetic counselling for the IHH families.

Facile Generation of Thermally Activated Delayed Fluorescence and Fabrication of Highly Efficient Non-Doped OLEDs Based on Triazine Derivatives.

A series of donor-acceptor-donor triazine-based molecules with thermally activated delayed fluorescence (TADF) properties were synthesized to obtain highly efficient blue-emitting OLEDs with non-doped emitting layers (EMLs). The targeted molecules use a triazine core as the electron acceptor, and a benzene ring as the conjugated linker with different electron donors to alternate the energy level of the HOMO to further tune the emission color. The introduction of long alkyl chains on the triazine core inhibits the unwanted intermolecular D-D/A-A-type π-π interactions, resulting in the intermolecular D-A charge transfer. The weak aggregation-caused quenching (ACQ) effect caused by the suppressed intermolecular D-D/A-A-type π-π interaction further enhances the emission. The crowded molecular structure allows the electron donor and acceptor to be nearly orthogonal, thereby reducing the energy gap between triplet and singlet excited states (ΔEST ). As a result, blue-emitting devices with TH-2DMAC and TH-2DPAC non-doped EMLs showed satisfactory efficiencies of 12.8 % and 15.8 %, respectively, which is one of the highest external quantum efficiency (EQEs) reported for blue TADF emitters (λpeak <475 nm), demonstrating that our tailored molecular designs are promising strategies to endow OLEDs with excellent electroluminescent performances.

Prenatal diagnosis of methylmalonic aciduria from amniotic fluid using genetic and biochemical approaches.

OBJECTIVES: This study reported the clinical prenatal diagnosis experience of families affected by methylmalonic acidemia (MMA) evaluated at a single prenatal diagnosis center over 8 years, and the reliability of a biochemical approach for prenatal diagnosis was analyzed. METHODS: Prenatal diagnosis data for 187 MMA families referred to our center from 2009 to 2016 were reviewed retrospectively. The results of the genetic analysis and biochemical approach were compared. RESULTS: A total of 41 MMA-affected pregnancies (21%) were identified. The biochemical analysis could identify the true status of 99.5% of fetuses. The diagnostic sensitivities of the propionylcarnitine (C3) level, the C3 to acetylcarnitine (C2) ratio (C3/C2), the methylmalonic acid, and methylcitrate levels in the amniotic fluid were 95.1%, 100%, 100%, and 82.9%, respectively, and the specificities were 98.7%, 99.3%, 97.4%, and 96.7%, respectively. CONCLUSIONS: The biochemical analysis could be optionally used in the prenatal diagnosis of MMA, especially in cases where the genetic results are inconclusive. Among the four tested biochemical markers, C3/C2 appeared to be the most reliable.

Ablation Versus Medical Therapy for Atrial Fibrillation in the Elderly: A Propensity Score-Matched Comparison.

BACKGROUND Whether ablation therapy reduces the risk of death and embolic events in elderly patients with atrial fibrillation (AF) remains unclear. MATERIAL AND METHODS AF patients ≥65 years old receiving either catheter ablation or non-ablation therapy at 2 tertiary and 2 non-tertiary hospitals in Beijing from November 2009 to December 2012 were enrolled. Patients were followed up every 6 months for information on treatment and clinical event occurrence. A propensity score matching algorithm produced comparable 2 groups of patients treated with ablation or non-ablation. Rates of a composite of all-cause death, non-fatal stroke, and peripheral embolism were the primary outcomes. Each composite component and major bleeding were the secondary outcomes. RESULTS There were 596 ablated patients and 1144 patients with non-ablation therapy enrolled. Propensity score algorithm matched 347 comparable pairs of patients. Patient characteristics variables were well balanced. During 523.5 and 497.5 patient-years follow-up, respectively, ablation therapy was associated with a significant lower risk of experiencing the primary composite outcome (hazard ratio [HR]=0.40; 95% confidence interval [CI]: 0.19-0.85), all-cause death (HR=0.13 95% CI: 0.04-0.43), and major bleeding (HR=0.23; 95% CI: 0.12-0.67), without apparent heterogeneity by age, sex, and AF type, and for risk score subgroups. CONCLUSIONS In this propensity-matched elderly sample, ablation therapy was associated with lower risk of composite outcome consisting of all-cause death, non-fatal stroke, and peripheral embolism, and therefore might be an alternative to conservative therapy.

Observation of local cardiac electrophysiological changes during off-pump coronary artery bypass grafting using epicardial mapping.

OBJECTIVES: At present, there is no effective method of evaluating the electrophysiological changes in cardiac myocytes during off-pump coronary artery bypass grafting (OPCAB). Therefore, we preliminarily explored the relationship between electrophysiological characteristics and the changes in cardiac function of 24 patients undergoing OPCAB. METHODS: We used the CARTO3 system for epicardial electrophysiological mapping before surgery, during left anterior descending branch anastomosis, diagonal branch anastomosis and after surgery for 24 patients undergoing OPCAB. Data, including local activation time (LAT), bipolar voltage value (BV) and conduction velocity, were processed and analyzed by the system. Intraoperative invasive blood pressure, heart rate and arterial blood gas analysis data were recorded. Continuous electrocardiography (ECG) monitoring was performed three days after surgery. Routine resting myocardial perfusion imaging (MPI) and adenosine stress-gated MPI were performed before surgery. Patients were re-examined before discharge. RESULTS: By analyzing the change in the LAT value, we found that the order of excitation of local myocardial cells changed after surgery. In addition, the LAT change in myocardial cells closer to the anastomosis was more significant. The earliest pacing point on the left anterior descending (LAD) coronary artery territory map was the third point (from the proximal to distal LAD) before OPCAB, but the earliest pacing point moved down to the fourth point (closer to the anastomosis) after the diagonal (DIA) anastomosis was complete. On the DIA territory map, the earliest pacing point was the fourth point before OPCAB; this moved up to the third point (closer to the anastomosis) after DIA bypass grafting. The voltages of all points were increased after myocardial revascularization. Compared with the preoperative period, the third, fourth and fifth points on the LAD territory map increased significantly after LAD anastomosis was complete (p=0.007, p=0.001, p=0.009, respectively). On the DIA territory map, the voltages of the first, second and third points were remarkably increased after completing the DIA anastomosis compared to before OPCAB and after LAD anastomosis completion (p=0.001, p=0.008, p<0.001 and p=0.006, p=0.032, p=0.002, respectively). The average conduction velocity (ACV) of all mapped points increased after OPCAB compared with before OPCAB (p<0.05). Postoperative resting MPI and adenosine stress-gated MPI showed that left ventricular global systolic function improved, the left ventricular ejection fraction (LVEF) increased significantly (p<0.05) and the left ventricular end systolic volume (LVESV) decreased significantly (p<0.05) compared to the preoperative MPI. CONCLUSIONS: Adequate surgical coronary revascularization could lead to more stable electrical activity of local cardiomyocytes, thus, illustrating the specific mechanism of coronary revascularization for improving the cardiac function from an electrophysiological perspective.

Transseptal puncture and catheter ablation of atrial fibrillation in patients with atrial septal occluder: initial experience of a single centre.

Aims: Catheter ablation is underutilized in atrial septal defect (ASD) patients who have undergone implantation of an atrial septal occluder (ASO). This study evaluates the feasibility and safety of catheter ablation of atrial fibrillation (AF) in this subset of patients. Methods and results: Sixteen patients (age 56 ± 12 years, 10 men) with drug-refractory AF (10 paroxysmal and 6 persistent) and previously implanted ASO were enrolled. Balloon dilatation of the closure device was performed if the native septum passage could not be achieved. For paroxysmal AF, the ablation strategy was circumferential pulmonary vein isolation (CPVI), and for persistent AF, additional linear ablation was performed. Transseptal access was achieved through the native septum in 11 patients (Group A) and through the ASO using balloon dilatation in 5 patients (Group B). Circumferential pulmonary vein isolation was achieved in all 16 patients, and linear block was achieved in all persistent patients except for 1 patient who did not achieve mitral isthmus block. The transseptal, total fluoroscopy, and procedural durations were 5 ± 3 vs. 38 ± 8 min, 31 ± 11 vs. 54 ± 15 min, and 165 ± 35 vs. 224 ± 36 min, respectively, in Group A vs. Group B, respectively (all P < 0.05). No shunt at atrial level was detected by transthoracic echocardiography at 3-month follow-up. During a follow-up of 16 ± 6 months, sinus rhythm was maintained in 12 of 16 patients. No severe complications were observed. Conclusion: In ASD patients with ASO, catheter ablation of AF is feasible, safe, and effective. The balloon dilatation technique can facilitate transseptal access through the ASO.

miR-200b inhibits TNF-α-induced IL-8 secretion and tight junction disruption of intestinal epithelial cells in vitro.

Inflammatory bowel diseases (IBDs) are chronic, inflammatory disorders of the gastrointestinal tract with unclear etiologies. Intestinal epithelial cells (IECs), containing crypt and villus enterocytes, occupy a critical position in the pathogenesis of IBDs and are a major producer of immunoregulatory cytokines and a key component of the intact epithelial barrier. Previously, we have reported that miR-200b is involved in the progression of IBDs and might maintain the integrity of the intestinal epithelial barrier via reducing the loss of enterocytes. In this study, we further investigated the impact of miR-200b on intestinal epithelial inflammation and tight junctions in two distinct differentiated states of Caco-2 cells after TNF-α treatment. We demonstrated that TNF-α-enhanced IL-8 expression was decreased by microRNA (miR)-200b in undifferentiated IECs. Simultaneously, miR-200b could alleviate TNF-α-induced tight junction (TJ) disruption in well-differentiated IECs by reducing the reduction in the transepithelial electrical resistance (TEER), inhibiting the increase in paracellular permeability, and preventing the morphological redistribution of the TJ proteins claudin 1 and ZO-1. The expression levels of the JNK/c-Jun/AP-1 and myosin light chain kinase (MLCK)/phosphorylated myosin light chain (p-MLC) pathways were attenuated in undifferentiated and differentiated enterocytes, respectively. Furthermore, a dual-luciferase reporter gene detection system provided direct evidence that c-Jun and MLCK were the specific targets of miR-200b. Collectively, our results highlighted that miR-200b played a positive role in IECs via suppressing intestinal epithelial IL-8 secretion and attenuating TJ damage in vitro, which suggested that miR-200b might be a promising strategy for IBD therapy. NEW & NOTEWORTHY: This was the first time that the inhibitory role of miR-200b on intestinal epithelial inflammation and paracellular permeability has been reported. Moreover, we further divided the intestinal epithelial cells (IECs) into two differentiated conditions and investigated the distinct impacts of miR-200b. Finally, we put forward and proved that myosin light chain kinase (MLCK) was a novel target of miR-200b.