Plasma 8-Hydroxy-2'-Deoxyguanosine, a Potential Valuable Biomarker for Atrial Fibrosis Is Influenced by Polymorphism of DNA Methylation Gene.

BACKGROUND: Previous studies revealed a relationship between 8-hydroxy-2'-deoxyguanosine (8-OHdG) and the occurrence/recurrence of atrial fibrillation (AF). This 2-part study aimed to validate whether DNA damage related to 8-OHdG is associated with left atrial (LA) fibrosis in AF patients quantified by voltage mapping (Part I), and to identify the underlying genetic components regulating the 8-OHdG level (Part II).Methods and Results: Plasma 8-OHdG determination, DNA extraction, and genotyping were conducted before catheter ablation. LA voltage mapping was performed under sinus rhythm. According to the percentage of low voltage area (LVA), patients were categorized as stage I (<5%), stage II (5-10%), stage III (10-20%), and stage IV (>20%). Part I included 209 AF patients. The 8-OHdG level showed an upward trend together with advanced LVA stage (stage I 8.1 [6.1, 10.5] ng/mL, stage II 8.5 [5.7, 14.1] ng/mL, stage III 14.3 [12.1, 16.5] ng/mL, stage IV 13.9 [10.5, 16.0] ng/mL, P<0.000). Part II included 175 of the 209 patients from Part I. Gene-set analysis based on genome-wide association study summary data identified that the gene set named 'DNA methylation on cytosine' was the only genetic component significantly associated with 8-OHdG concentration. CONCLUSIONS: Higher 8-OHdG levels may predict more advanced LVA of the LA in AF patients. DNA methylation is the putative genetic component underlying oxidative DNA damage in AF patients.

Predictors of pacemaker implantation within three months after catheter ablation of atrial fibrillation.

BACKGROUND: It is inevitable for patients to have a temporary or permanent pacemaker implanted during or after radiofrequency catheter ablation (RFCA) for treatment of atrial fibrillation (AF) in some cases. The aim of our study was to evaluate the incidence of pacemaker implantation (PMI) during or within 3 months of RFCA for AF and to identify the risk factors that were associated with PMI. METHODS: We performed a retrospective analysis of consecutive AF patients who underwent RFCA between August 2018 and October 2020 at our center. The incidence of PMI within 3 months during or after RFCA were assessed. A multivariate logistic regression model was performed to identify predictors of PMI. RESULTS: One thousand and five patients (mean age, 60.2 ± 10.3 years; 37.6% women) were included in this analysis. PVI was performed in all patients. A total of 23 (2.3%) patients had a pacemaker implanted within 3 months during or after ablation. Multivariable logistic regression analysis revealed that older age (OR: 1.08 [95% CI 1.03-1.13], p = .003), female sex (OR: 3.08 [95% CI 1.28-7.45], p = .012), paroxysmal AF (OR: 4.71 [95% CI 1.09-20.45], p = .038) and repeated ablation (OR: 2.78 [95% CI 1.04-7.40], p = .041) were the independent predictors for PMI. CONCLUSIONS: Older age, female sex, paroxysmal AF and repeated ablation were identified as predictive risk factors for PMI after RFCA in patients with AF. A "watch and wait" strategy could be taken for patients with temporary PMI after ablation, especially for those with prolonged sinus pause after AF termination.

Convolutional Neural Networks for Classifying Cervical Cancer Types Using Histological Images.

Cervical cancer is the most common cancer among women worldwide. The diagnosis and classification of cancer are extremely important, as it influences the optimal treatment and length of survival. The objective was to develop and validate a diagnosis system based on convolutional neural networks (CNN) that identifies cervical malignancies and provides diagnostic interpretability. A total of 8496 labeled histology images were extracted from 229 cervical specimens (cervical squamous cell carcinoma, SCC, n = 37; cervical adenocarcinoma, AC, n = 8; nonmalignant cervical tissues, n = 184). AlexNet, VGG-19, Xception, and ResNet-50 with five-fold cross-validation were constructed to distinguish cervical cancer images from nonmalignant images. The performance of CNNs was quantified in terms of accuracy, precision, recall, and the area under the receiver operating curve (AUC). Six pathologists were recruited to make a comparison with the performance of CNNs. Guided Backpropagation and Gradient-weighted Class Activation Mapping (Grad-CAM) were deployed to highlight the area of high malignant probability. The Xception model had excellent performance in identifying cervical SCC and AC in test sets. For cervical SCC, AUC was 0.98 (internal validation) and 0.974 (external validation). For cervical AC, AUC was 0.966 (internal validation) and 0.958 (external validation). The performance of CNNs falls between experienced and inexperienced pathologists. Grad-CAM and Guided Gard-CAM ensured diagnoses interpretability by highlighting morphological features of malignant changes. CNN is efficient for histological image classification tasks of distinguishing cervical malignancies from benign tissues and could highlight the specific areas of concern. All these findings suggest that CNNs could serve as a diagnostic tool to aid pathologic diagnosis.

The effect of air pollution on Chinese green bond market: The mediation role of public concern.

Green bonds are becoming increasingly important in sustainable investments since their environmental protection attributes allow them to benefit from environmental degradation. However, the mechanism of environmental degradation on green bonds has not yet been studied. This study proposes a mediation model to analyze air pollution's influence on green bonds. Theoretically, air pollution leads to increased public concern through public environmental awareness and perceptions of physical health risks. Enhanced public concern drives investors' green preference and environmental responsibility, thus expanding green bond demand, in which public concern plays an important mediation role. To verify the mediating effect, causal stepwise regression and bootstrap methods are used. The empirical results confirm this theoretical mechanism. Air pollution is significantly positively related to public concern. Public concern is positively linked with green bond investment willingness, resulting in increased volatility. The total positive effect of air pollution on green bonds is partly absorbed by the mediating effect of public concern that is significantly positive and reaches 30.21% of the total effect. In addition, major crisis events (e.g., COVID-19) may hinder the positive mediation process by generating a negative trend and distracting the public. This means that the government could propose appropriate measures to minimize the negative aspects in order to promote green finance. The mediation model is also useful for investors wishing to increase green assets in their portfolios and provides an incentive for businesses to promote green finance.

Nuclear DNA replicates during zygote development in Arabidopsis and Torenia fournieri.

The progression of the cell cycle is continuous in most cells, but gametes (sperm and egg cells) exhibit an arrest of the cell cycle to await fertilization to form a zygote, which then continues through the subsequent phases to complete cell division. The phase in which gametes of flowering plants arrest has been a matter of debate, since different phases have been reported for the gametes of different species. In this study, we reassessed the phase of cell-cycle arrest in the gametes of two species, Arabidopsis (Arabidopsis thaliana) and Torenia fournieri. We first showed that 4', 6-diamidino-2-phenylindole staining was not feasible to detect changes in gametic nuclear DNA in T. fournieri. Next, using 5-ethynyl-2'-deoxyuridine (EdU) staining that detects DNA replication by labeling the EdU absorbed by deoxyribonucleic acid, we found that the replication of nuclear DNA did not occur during gamete development but during zygote development, revealing that the gametes of these species have a haploid nuclear DNA content before fertilization. We thus propose that gametes in the G1 phase participate in the fertilization event in Arabidopsis and T. fournieri.

Strategy for Failed Transvenous Left-Ventricular Lead Placement in Cardiac Resynchronization Therapy: Surrender or Struggle?

INTRODUCTION: For those cardiac resynchronization therapy (CRT) candidates who experience left-ventricular (LV) lead placement failure or underwent concomitant cardiac surgeries, surgical placement of epicardial LV lead guided by electroanatomic mapping may be a promising alternative. METHODS: Electroanatomic mapping was used to guide positioning of the LV lead through a surgical approach. The LV lead was placed at the region with the latest local LV activation and normal voltage, away from the scar. RESULTS: From April 2010 to September 2018, 10 consecutive patients (3 female) underwent surgical epicardial LV lead implantation. Among them, 3 had other surgical indications simultaneously (including 1 CRT non-responder), and 7 had failed transvenous LV lead placement. After CRT, the QRS duration was shortened from 149.3 ± 20.4 ms to 125.1 ± 15.2 ms (p = 0.01). At 6 months, the LV ejection fraction was significantly improved and remained stable in the follow-up (FU) period thereafter (baseline vs. 6 months, 31.0 ± 8.3% vs. 42.2 ± 13.4%, p = 0.006). Other parameters, including the threshold and impedance of the LV lead, were also stable at a mean FU of 755 ± 406 days, and the NYHA functional classification decreased from 2.9 ± 0.7 to 1.8 ± 0.8 (p = 0.002). CONCLUSIONS: Placement of an epicardial LV lead guided by electroanatomic mapping could be used as an adjunctive strategy in patients who were unable or refractory to conventional CRT therapy. This approach could also be applied in patients who had other surgical indications at the same time.

GDF11 knockdown downregulates SMURF1 to inhibit breast cancer progression by activation of p53 and inactivation of ERα signaling.

Breast cancer (BC) is a prevalent neoplasm that occurs in women all over the world. Growth and differentiation factor 11 (GDF11) plays an essential role in cancer progression. This study focused on investigating the biological role and underlying mechanisms of GDF11 in BC. We detected the expression of GDF11 in 27 patients with BC and BC cell lines. Kaplan-Meier plotter was employed to analyze the relationship between GDF11 expression and overall survival (OS) of BC patients. The proliferative, migratory, invasive, and apoptotic abilities of T47D cells were examined. Correlation analysis of GDF11 with Smad ubiquitination regulatory factor 1 (SMURF1) was conducted. The association between GDF11 and the p53 pathway was analyzed by western blot and PFT-α (a p53 inhibitor)-mediated rescue assays. A brief analysis of the role of estrogen receptor alpha (ERα) signaling in BC progression was performed. The results showed that GDF11 was increased in BC tissues and cell lines, and the high expression of GDF11 was associated with the poor OS of BC patients. GDF11 knockdown inhibited the proliferation, migration, and invasion of T47D cells, but promoted cell apoptosis. Meanwhile, the GDF11 knockdown reduced the SMURF1 expression and invoked the p53 pathway activation. SMURF1 overexpression and PFT-α partially blocked the effects of GDF11 knockdown. In addition, GDF11 knockdown and SMURF1 silencing inhibited the activation of the ERα signaling pathway. In summary, GDF11 was involved in the progression of BC by regulating SMURF1-mediated p53 and ERα pathways, opening up a new way for BC treatment.

Ginsenoside Rb1 reduces oxidative/carbonyl stress damage and ameliorates inflammation in the lung of streptozotocin-induced diabetic rats.

CONTEXT: Ginsenoside Rb1 (Rb1) is a biologically active component of ginseng [Panax ginseng C.A. Meyer (Araliaceae)]. OBJECTIVE: This study determined the underlying mechanisms of Rb1 treatment that acted on diabetes-injured lungs in diabetic rats. MATERIALS AND METHODS: Streptozotocin (STZ)-induced diabetic rat model was used. Male Sprague-Dawley (SD) rats were divided into four groups (n = 10): control, Rb1 (20 mg/kg), insulin (15 U/kg to attain the euglycaemic state) and diabetic (untreated). After treatment for six weeks, oxidative stress assay; histological and ultrastructure analyses; TNF-α, TGF-ß, IL-1 and IL-6 protein expression analyses; and the detection of apoptosis were performed. RESULTS: There was decreased activity of SOD (3.53-fold), CAT (2.55-fold) and GSH (1.63-fold) and increased levels of NO (4.47-fold) and MDA (3.86-fold) in the diabetic group from control. Rb1 treatment increased SOD (2.4-fold), CAT (1.9-fold) and GSH (1.29-fold) and decreased the levels of NO (1.76-fold) and MDA (1.51-fold) as compared with diabetic rats. The expression of IL-6 (5.13-fold), IL-1α (2.35-fold), TNF-α (2.35-fold) and TGF-ß (2.39-fold) was increased in diabetic rats from control. IL-6 (2.43-fold), IL-1α (2.27-fold), TNF-α (1.68-fold) and TGF-ß (2.3-fold) were decreased in the Rb1 treatment group. Diabetes increased the apoptosis rate (2.23-fold vs. control), and Rb1 treatment decreased the apoptosis rate (1.73-fold vs. the diabetic rats). Rb1 and insulin ameliorated lung tissue injury. DISCUSSION AND CONCLUSIONS: These findings indicate that Rb1 could be useful for mitigating oxidative damage and inflammatory infiltration in the diabetic lung.

A competitive PCR-based method to detect a single copy of T-DNA insertion in transformants.

Gene function studies benefit from the availability of mutants. In plants, Agrobacterium-mediated genetic transformation is widely used to create mutants. These mutants, also called transformants, contain one or several transfer-DNA (T-DNA) copies in the host genome. Quantifying the copy number of T-DNA in transformants is beneficial to assess the number of mutated genes. Here, we developed a competitive polymerase chain reaction (PCR)-based method to detect a single copy of a T-DNA insertion in transformants. The competitor line BHK- -1 that contains a single copy of competitor BHK- (BHK, Basta, Hygromycin, Kanamycin-resistant genes) was crossed with test transformants and the genomic DNA of F1 plants was subjected to competitive PCR. By analyzing the gray ratio between two PCR products, we were able to determine whether or not the test transformants contained a single copy of T-DNA insertion. We also generated the control lines BHK±1:1 and BHK±2:1 , which contain the target (BHK+ ) and competitor (BHK- ) in a ratio of 1:1 and 2:1, respectively. The ratios of their PCR products are useful references for quantitative analysis. Overall, this method is reliable and simple in experimental manipulations and can be used as a substitute for Southern-blot analysis to identify a single copy of T-DNA insertion in transformants.

Causal effects of plasma lipids on the risk of atrial fibrillation: A multivariable mendelian randomization study.

BACKGROUND AND AIMS: Observational studies have suggested that plasma lipids contribute substantially to cardiovascular disease, but "cholesterol paradox" in atrial fibrillation (AF) remains. We sought to investigate the causal effects of lipid profiles on the risk of AF. METHODS AND RESULTS: Two-sample Mendelian randomization (MR) framework was implemented to examine the causality of association. Summary estimations of genetic variants associated with low density lipoprotein (LDL)-cholesterol, high density lipoprotein (HDL)-cholesterol, total cholesterol, triglycerides, lipoprotein-a [Lp(a)], apolipoprotein A1 (ApoA 1), and apolipoprotein B (ApoB) were 81, 99, 96, 61, 30, 10, and 23 single nucleotide polymorphisms, respectively. Genetic association with AF were retrieved from a genome-wide association study that included 1,030,836 individuals. The complications for AF were predefined as cardioembolic stroke (CES) and heart failure (HF). In the multivariable MR, the odds ratios for AF per standard deviation (SD) increase were 1.030 (95% confidence interval (CI) 0.979-1.083; P = 0.257) for LDL-cholesterol, 0.986 (95% CI 0.931-1.044; P = 0.622) for HDL-cholesterol, 0.965 (95% CI 0.896-1.041; P = 0.359) for triglycerides, 1.001 (95% CI 1.000-1.003; P = 0.023) for Lp(a), 1.017 (95% CI 0.966-1.070; P = 0.518) for ApoA1, and 1.002 (95% CI 0.963-1.043; P = 0.923) for ApoB. There was no evidence that other lipid components were causally associated with AF, CES, or HF, other than for a marginal association between triglycerides and HF. CONCLUSIONS: This MR study provides robust evidence that high Lp(a) increases the risk of AF, suggesting that interventions targeting Lp(a) may contribute to the primary prevention of AF.

No association between alcohol consumption and risk of atrial fibrillation: A two-sample Mendelian randomization study.

BACKGROUND AND AIMS: Although many observational studies have suggested that alcohol intake was associated with incident atrial fibrillation (AF), controversy remains. This study aimed to examine the causal association of alcohol intake with the risk of AF. METHODS AND RESULTS: Two-sample Mendelian randomization (MR) analysis was performed to estimate the causal effects of alcohol consumption, alcohol dependence, or alcohol use disorder identification test (AUDIT) scores on AF. Summary data on single nucleotide polymorphisms (SNPs) associated with AF were obtained from a genome-wide association study (GWAS) with up to 1,030,836 participants. The fixed- and random-effect inverse-variance weighted (IVW) methods were used to calculate the overall causal effects. MR analysis revealed nonsignificant association of genetically predicted alcohol consumption with risk of AF using fixed- and random-effect IVW approaches (odds ratio (OR) [95% confidence interval (CI)] = 1.004 [0.796-1.266], P = 0.975; OR [95% CI] = 1.004 [0.766-1.315], P = 0.979). Genetically predicted alcohol dependence was also not causally associated with AF in the fixed- and random-effect IVW analyses (OR [95% CI] = 1.012 [0.978-1.048], P = 0.490; OR [95% CI] = 1.012 [0.991-1.034], P = 0.260). There was no significantly causal association between AUDIT and AF in the fixed- and random-effect IVW analyses (OR [95% CI] = 0.889 [0.433-1.822], P = 0.748; OR [95% CI] = 0.889 [0.309-2.555], P = 0.827). Sensitivity analyses indicated no evidence of pleiotropy and heterogeneity in statistical models. CONCLUSIONS: This MR study did not find evidence of a causal association between alcohol intake and AF.

Rapid Electrical Stimulation Increased Cardiac Apoptosis Through Disturbance of Calcium Homeostasis and Mitochondrial Dysfunction in Human Induced Pluripotent Stem Cell-Derived Cardiomyocytes.

BACKGROUND/AIMS: Heart failure induced by tachycardia, the most common arrhythmia, is frequently observed in clinical practice. This study was designed to investigate the underlying mechanisms. METHODS: Rapid electrical stimulation (RES) at a frequency of 3 Hz was applied on human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) for 7 days, with 8 h/day and 24 h/day set to represent short-term and long-term tachycardia, respectively. Age-matched hiPSC-CMs without electrical stimulation or with slow electrical stimulation (1 Hz) were set as no electrical stimulation (NES) control or low-frequency electrical stimulation (LES) control. Following stimulation, JC-1 staining flow cytometry analysis was performed to examine mitochondrial conditions. Apoptosis in hiPSC-CMs was evaluated using Hoechst staining and Annexin V/propidium iodide (AV/PI) staining flow cytometry analysis. Calcium transients and L-type calcium currents were recorded to evaluate calcium homeostasis. Western blotting and qPCR were performed to evaluate the protein and mRNA expression levels of apoptosis-related genes and calcium homeostasis-regulated genes. RESULTS: Compared to the controls, hiPSC-CMs following RES presented mitochondrial dysfunction and an increased apoptotic percentage. Amplitudes of calcium transients and L-type calcium currents were significantly decreased in hiPSC-CMs with RES. Molecular analysis demonstrated upregulated expression of Caspase3 and increased Bax/Bcl-2 ratio. Genes related to calcium re-sequence were downregulated, while phosphorylated Ca2+/calmodulin-dependent protein kinase II (CaMKII) was significantly upregulated following RES. There was no significant difference between the NES control and LES control groups in these aspects. Inhibition of CaMKII with 1 µM KN93 partly reversed these adverse effects of RES. CONCLUSION: RES on hiPSC-CMs disturbed calcium homeostasis, which led to mitochondrial stress, promoted cell apoptosis and caused electrophysiological remodeling in a time-dependent manner. CaMKII played a central role in the damages induced by RES, pharmacological inhibition of CaMKII activity partly reversed the adverse effects of RES on both structural and electrophysiological properties of cells.

What is the impact of n-3 PUFAs on inflammation markers in Type 2 diabetic mellitus populations?: a systematic review and meta-analysis of randomized controlled trials.

OBJECTIVES: To explore the possible role of n-3 polyunsaturated fatty acids (PUFAs) in lowering inflammation markers in individuals with type 2 diabetes mellitus. METHODS: PubMed, CNKI and Cochrane databases were searched until December 30, 2015; references from papers or reviews were also retrieved and screened. Screening was performed by two independent researchers, and randomized controlled trials reporting the specific n-3 PUFA type, dose, frequency, and duration of treatment, as well as the baseline and follow-up concentrations of inflammation markers, including interleukin 2 (IL-2), interleukin 6 (IL-6), tumor necrosis factor alpha (TNF-α) and C-reactive protein (CRP), were selected for final analysis. Data analysis was performed using RevMan 5.2 software. RESULTS: Eight studies involving 955 participants were included; all reported CRP. Only one included study reported IL-2 or IL-6 while two studies reported TNF-α. N-3 PUFAs significantly reduced CRP concentration compared with control [SMD 95 % CI, 1.90 (0.64, 3.16), Z = 2.96, P = 0.003, random effect model]. CONCLUSIONS: N-3 PUFAs decrease CRP concentration in type-2 diabetes mellitus. However, larger and rigorously designed RCTs are required to confirm this finding and extend it into other inflammatory biomarkers.

Down-regulation of ATBF1 activates STAT3 signaling via PIAS3 in pacing-induced HL-1 atrial myocytes.

Atrial fibrillation (AF) is progressive and is the most common clinical arrhythmia. It is associated with inflammatory changes characterized by signal transducer and activator of transcription 3 (STAT3) signaling. A zinc finger homeobox 3 (ZFHX3, also named AT-motif binding factor 1, ATBF1) gene variant has been found in patients with AF. However, the mechanism by which the ATBF1 leads to inflammation in AF remains unknown. The aim of this study was to investigate whether tachypacing induces a decrease in ATBF1 expression and then activates STAT3 signaling via protein inhibitor of activated STAT3 (PIAS3). Atrial (HL-1 myocytes) cells were cultured in the presence of rapid electrical stimulations. In tachypaced HL-1 cells, we found that ATBF1 and PIAS3 protein levels were decreased, while the level of phosphorylated STAT3 (p-STAT3) was highly up-regulated compared with that of total STAT3. Knockdown of ATBF1 enhanced this trend, while the overexpression of ATBF1 had the opposite effect. A binary complex of ATBF1 and PIAS3 was formed and then the DNA-binding ability of activated STAT3 was enhanced in tachypaced HL-1 cells. These data indicate that tachypacing decreased ATBF1, leading to enhanced STAT3 DNA-binding activity due to the reduced formation of a binary complex of ATBF1 and PIAS3.

Barriers and facilitators to using ophthalmic clinical health services following school vision screening: a mixed-methods study.

OBJECTIVE: To identify determinants of the utilisation of ophthalmic clinical health services among students who failed school vision screening. METHODS: This study employed a sequential explanatory mixed methods design, underpinned by Andersen's Behavioural Model of Health Service Utilisation. Data were initially gathered through interviews with 27 stakeholders-comprising 5 ophthalmologists, 7 community doctors, 7 public health professionals and 8 teachers. The qualitative insights informed the construction of a questionnaire, which subsequently garnered responses from 6215 participants. Qualitative data underwent thematic analysis with NVivo V.12, while quantitative data were analysed using multivariable multinomial logistic regression in SAS V.9.4. Data integration was performed using the Pillar Integration Process for a deductive, evidence-based synthesis of findings. RESULTS: The research revealed that students attending vision demonstration schools and receiving encouragement from schools or communities to access clinical ophthalmic services demonstrated higher adherence to referral (OR=1.66, 95% CI 1.30 to 2.12; OR=1.54, 95% CI 1.33 to 1.80). Conversely, older students and those from higher-income families exhibited lower adherence rates (OR=0.31, 95% CI 0.23 to 0.44; OR=0.34, 95% CI 0.25 to 0.46). Moreover, students with less urgent medical needs were more likely to adhere to referrals compared with those needing immediate referrals (OR=1.24, 95% CI 1.06 to 1.45).Four pillars emerged: (a) adherence decreased with age, (b) financial constraints did not pose an obstacle, (c) public health services played a critical role, (d) referral urgency did not linearly correlate with adherence. CONCLUSION: The utilisation of ophthalmic clinical health services following vision screening failure in students is significantly influenced by public health services provided by schools or communities, such as prompting those with abnormal screening results to access ophthalmic clinical health services.

Arrhythmogenic Right Ventricular Cardiomyopathy With Extensive Abnormal Substrate: Is Isolation Possible?

BACKGROUND: In arrhythmogenic right ventricular cardiomyopathy (ARVC) patients with extensive right ventricular free wall (RVFW) abnormal substrate, large-area homogenization with combined epicardial and endocardial approach is time consuming and often inadequate for modification. OBJECTIVES: This study aimed to explore the feasibility and efficacy of RVFW abnormal substrate isolation in such patients to control ventricular tachycardia (VT). METHODS: Eight consecutive ARVC patients with VT who had extensive abnormal RVFW substrate were included. VT induction was performed before substrate mapping and modification. Detailed voltage mapping was done during sinus rhythm. A circumferential linear lesion was deployed along the border zone of low-voltage area on the RVFW to achieve electrical isolation. Other small areas with fractionated or late potentials were further homogenized. RESULTS: All 8 patients had RVFW endocardial low-voltage area. The entire RV low-voltage area was 113.8 ± 84.1 cm2 (49.6% ± 29.8%) and the dense scar was 59.6 ± 39.8 cm2 (25.0% ± 14.1%). Electrical isolation of abnormal substrate was achieved in 5 of 8 (62.5%) patients via endocardial approach alone and 3 of 8 (37.5%) patients via a combination of endocardial and epicardial approach. Electrical isolation was verified by slow automaticity (5 of 8, 62.5%) or RV noncapture (3 of 8, 37.5%) during high-output pacing inside the encircled area. VTs were induced in 6 patients before ablation, and all patients were rendered noninducible after ablation. During a median follow-up of 43 months (range: 24-53 months), 7 of 8 (87.5%) patients remained free of sustained VT. CONCLUSIONS: Electrical isolation of RVFW is feasible and can be the option in ARVC patients with extensive abnormal substrate.

Characteristics, Thrombus Resolution, and Long-Term Outcomes in Patients with Nonvalvular Atrial Fibrillation and Atrial Thrombus.

To assess the prevalence and management of atrial thrombus in patients with nonvalvular atrial fibrillation (NVAF) and identify the risk factors of the nonresolution of atrial thrombus. This single-center retrospective observational study consecutively enrolled patients with NVAF and atrial thrombus detected using transesophageal echocardiography (TEE) or cardiac computed tomography angiography (CTA) from January 2012 to December 2020. Patients with prior left atrial appendage (LAA) intervention were excluded. The primary endpoint was the presence of atrial thrombus, while the secondary endpoint was the complete resolution of atrial thrombus. The prevalence of atrial thrombus in patients with NVAF was 1.4%. Ninety patients with atrial thrombus (mean age 62.8 ± 11.9 years and 61.1% men) were finally analyzed. Atrial thrombus was in the LAA in 82 (91.1%) patients. During follow up, 60% of the patients showed complete resolution of atrial thrombus. Congestive heart failure (odds ratio [OR]: 8.94; 95% confidence interval [CI]: 1.67-47.80) and a history of ischemic stroke (OR: 8.28; 95% CI: 1.48-46.42) were independently associated with the risk of the nonresolution of atrial thrombus. The presence of atrial thrombus in patients with NVAF who received anticoagulation therapy is non-negligible. Even in anticoagulated patients, TEE or cardiac CTA might still be needed. Congestive heart failure and a history of ischemic stroke are risk factors of the nonresolution of atrial thrombus.

Right-to-left shunts in unexplained syncope: an age- and sex-matched case-control study.

Background: Syncope is common, but there is no clear cause for half of the patients diagnosed with syncope. Although suspected, there is limited evidence that right-to-left shunt (RLS) is related to syncope. This matched case-control study investigated the association between RLS (exposure) and unexplained syncope (outcome). Methods: Consecutive unexplained syncope cases, together with age- and gender-matched controls who did not have syncope were recruited from 2009 to 2010 in the first affiliated hospital of Nanjing Medical University. A transcranial Doppler ultrasonography bubble test was applied for the ascertainment of RLS. The degree of RLS was categorized into grades 0 to 4 according to the number of microemboli, which were no shunt, <10 microbubbles (MB), 11-25 MB, >25 MB single spots pattern, and MB in a shower/curtain pattern, respectively. Cerebral small vessel diseases (SVD), including white matter hyperintensity, lacunes, and enlarged perivascular spaces, were rated on Magnetic resonance imaging. Conditional logistic regression was used to examine the association between RLS and unexplained syncope. Results: A total of 52 cases and 52 age- and gender-matched controls were recruited. Among the 52 cases, 4 patients had a history of migraine. Among the 104 participants, 68 had no RLS; 13, 4, 7, and 12 presented with <10, 11-25, >25, and shower/curtain MB, respectively. The incidence of any RLS (Grade 1-4) was 48.1% (25/52) in cases and 21.2% (11/52) in controls (P=0.004). Conditional logistic regression showed an association between RLS and unexplained syncope [odds ratio (OR) =1.988; 95% confidence interval (CI): 1.233 to 3.205; P=0.005] adjusting for SVD burden. Further analysis revealed a large OR between severe RLS (Grade 3-4) and unexplained syncope (OR =8.699; P=0.006). Furthermore, SVD burden was shown to be associated with syncope. Conclusions: This matched case-control study showed a significant association between RLS and unexplained syncope, independent of cerebral SVD. Prospective studies are needed to confirm the causal relationship.

Genetic findings in patients with primary fibrotic atrial cardiomyopathy.

Primary fibrotic atrial cardiomyopathy (PF-ACM) is a novel type of cardiomyopathy characterized by primary atrial fibrosis with arrhythmogenicity and increased stroke risk without ventricular myocardium involvement. However, genetic analysis regarding PF-ACM and genotype-phenotype correlations is lacking. A cohort of PF-ACM patients was recruited and followed up. Whole-exome sequencing (WES) was applied, and genes were screened using a cardiovascular disease (CVD)-related gene panel. Echocardiography and cardiac magnetic resonance (CMR) were performed. The pathogenicity of the identified mutations was evaluated using in silico analysis. Thirty-three unrelated patients were referred for WES. Thirty-three rare variants of 19 CVD-related genes were identified in 21 patients, with 10 patients harboring more than one variation. TTN was the most frequent gene observed. Further analysis demonstrated that variations in sarcomeric (SV) or non-sarcomeric (NSV) genes were found in 16 and 10 patients, respectively. Patients carrying variants regardless of SV or NSV had larger left atrial dimensions determined by echo and larger left atrium areas determined by CMR. There was no discrepancy in disease severity between SV carriers and NSV carriers. Our genetic investigation into PF-ACM has identified several genetic culprits, providing further insight into its underlying pathophysiology and emphasizing a potential role for genetic testing for this condition.

Azoramide ameliorated tachypacing-induced injury of atrial myocytes differentiated from human induced pluripotent stem cell by regulating endoplasmic reticulum stress.

Hypoglycemicagents have been shown to reduce the incidence of atrial fibrillation (AF) in patients with diabetes mellitus. Azoramide is a novel anti-diabetic agent which protects cells against endoplasmic reticulum (ER) stress; however, the cardioprotective effect of azoramide against AF is not clear. In this study, we aimed to investigate the protective effect of azoramide in human iPS-derived atrial myocytes (a-iCMs) against injury induced by high-frequency electrical stimulation. Human-induced pluripotent stem cells were differentiated into a-iCMs by treatment of retinoic acid. The tachypacing group was subjected to 7 Hz tachypacing for 48 h. Azoramide was preconditioned 2-hours before tachypacing. a-iCMs expressed atria-specific genes and the characteristics of the action potential were analogous to those of human atrial myocytes. Tachypacing induced disorder of intracellular calcium homeostasis, apoptosis, depressed ATP level, and severer myofilament dissolution. MetaboAnalysis revealed that tachypacing induced remarkable changes in metabolites involved in energy, amino acid, and glucose metabolism, whereas there was no significant effect on lipid metabolism. Azoramide pretreatment partly alleviated tachypacing-induced calcium dyshomeostasis, ATP consumption, and accelerated apoptosis, which was likely achieved by regulating the PERK/CHOP/CaMKII pathway. Azoramide protected atrial myocytes against injury induced by high-frequency electrical stimulation by regulating ER stress, which may inhibit cell apoptosis and calcium dyshomeostasis via the PERK/CHOP/CaMKII pathway.