Transcriptomic analysis of epicardial adipose tissue reveals the potential crosstalk genes and immune relationship between type 2 diabetes mellitus and atrial fibrillation.

BACKGROUND: The complex relationship between atrial fibrillation (AF) and type 2 diabetes mellitus (T2DM) suggests a potential role for epicardial adipose tissue (EAT) that requires further investigation. This study employs bioinformatics and experimental approaches to clarify EAT's role in linking T2DM and AF, aiming to unravel the biological mechanisms involved. METHOD: Bioinformatics analysis initially identified common differentially expressed genes (DEGs) in EAT from T2DM and AF datasets. Pathway enrichment and network analyses were then performed to determine the biological significance and network connections of these DEGs. Hub genes were identified through six CytoHubba algorithms and subsequently validated biologically, with further in-depth analyses confirming their roles and interactions. Experimentally, db/db mice were utilized to establish a T2DM model. AF induction was executed via programmed transesophageal electrical stimulation and burst pacing, focusing on comparing the incidence and duration of AF. Frozen sections and Hematoxylin and Eosin (H&E) staining illuminated the structures of the heart and EAT. Moreover, quantitative PCR (qPCR) measured the expression of hub genes. RESULTS: The study identified 106 DEGs in EAT from T2DM and AF datasets, underscoring significant pathways in energy metabolism and immune regulation. Three hub genes, CEBPZ, PAK1IP1, and BCCIP, emerged as pivotal in this context. In db/db mice, a marked predisposition towards AF induction and extended duration was observed, with HE staining verifying the presence of EAT. Additionally, qPCR validated significant changes in hub genes expression in db/db mice EAT. In-depth analysis identified 299 miRNAs and 33 TFs as potential regulators, notably GRHL1 and MYC. GeneMANIA analysis highlighted the hub genes' critical roles in stress responses and leukocyte differentiation, while immune profile correlations highlighted their impact on mast cells and neutrophils, emphasizing the genes' significant influence on immune regulation within the context of T2DM and AF. CONCLUSION: This investigation reveals the molecular links between T2DM and AF with a focus on EAT. Targeting these pathways, especially EAT-related ones, may enable personalized treatments and improved outcomes.

Efficiency of optimal fluoroscopic projection angle defined by computed tomography angiography for left atrial appendage closure.

BACKGROUND: Left atrial appendage (LAA) closure (LAAC) procedures are conventionally performed using empirical fluoroscopic viewing angles. However, because the LAA is a highly variable anatomical structure, these angles cannot depict the LAA in the optimal position. The present study aimed to assess the efficiency of using a novel optimal fluoroscopic projection angle (OPA) for LAAC and to validate its feasibility. METHODS: The OPAs of the derivation cohort were acquired using cardiac computed tomography angiography (CCTA) to assess its superiority for depicting LAA depth versus traditional working angles (TAs) of RAO 30°, CAU 20°. The practicability of OPA-guided LAAC was demonstrated by comparison between clinical data from the validation cohort and those from a propensity-score matched (PSM) control group, as well as randomized controlled studies investigating LAAC. RESULTS: Of 705 patients in the derivation cohort, the median OPA was RAO 46°, CAU 31°. Compared with TA, the OPA depicted a longer mean (±SD) LAA depth (5.1 ± 4.4) mm and a larger orifice diameter (1.1 ± 1.1 mm), (P < 0.0001 for both). All 38 OPA-guided LAACs were successful, with a shorter mean procedure duration (42.9 ± 12.3 min versus [vs.] 107.2 ± 41.5 min; P < 0.0001) and reduced device consumption (1.08 vs. 1.5 per case), compared with the PSM control group. At the 3-month follow-up, the incidence of peri-device leak was 52.6% (20/38) detected by CCTA, with a mean leakage of 1.6 ± 0.8 mm. CONCLUSION: By unfolding the LAA depth and orifice diameter for a better view, OPA demonstrated the potential to optimize LAAC procedural efficiency, although further larger-scale studies are required to confirm this.

Effect of uninterrupted dabigatran or rivaroxaban on achieving ideal activated clotting time to heparin response during catheter ablation in patients with atrial fibrillation.

BACKGROUND: Uninterrupted use of oral anticoagulants before atrial fibrillation (AF) ablation can reduce the incidence of perioperative thromboembolic events. However, the effect of new oral anticoagulants on activated clotting time (ACT) in response to heparin during AF ablation in Chinese populations remains unknown. The aim of the present retrospective study was to investigate the value of ACTs in response to intraoperative heparin administration in patients using dabigatran or rivaroxaban. METHODS: From January 2018 to December 2021, a total of 173 patients undergoing AF ablation were included in the study, in which 101 patients were treated with dabigatran, 72 patients were treated with rivaroxaban. The intraoperative ACT values were examined in both groups. The incidence of periprocedural complications was evaluated. RESULTS: Initial heparin dosage (88 ± 19 U/kg vs. 78 ± 27 U/kg, P < 0.05), total heparin dosage (137 ± 41 U/kg vs. 106 ± 52 U/kg, P < 0.05) during the ablation procedure were higher in the dabigatran group than those in the rivaroxaban group. Mean ACT (280 ± 36 s vs. 265 ± 30 s, P < 0.05), and the percentage of ACTs within the therapeutic range (250-350 s) (74% ± 26% vs. 60% ± 29%, P < 0.05) were significantly lower in the dabigatran group than those in the rivaroxaban group, particularly in male patients. Furthermore, the average time of achieving the target ACT (250-350 s) was also found longer in the dabigatran group (P < 0.05) as compared with the rivaroxaban group. No significant difference was found in the incidence of periprocedural complications between the two groups. CONCLUSIONS: The anticoagulant effect of uninterrupted rivaroxaban therapy appears to be more stable and efficient than dabigatran administration during catheter ablation in patients with AF.

Salinomycin suppresses T24 cells by regulating KDM1A and the unfolded protein response pathway.

In recent years, salinomycin has been shown to exert an anticancer effect in a variety of tumors; however, its function and mechanism in bladder cancer (BC) remain unclear. This study examined the effect of salinomycin on bladder cancer and analyzed its regulatory mechanism. T24 cells were treated with different concentrations of salinomycin to detect subsequent changes in cell proliferation, apoptosis, oxidative stress, H3K4 methylation, and related gene expression by the CCK8 assay, Edu staining, Tunel staining, ELISA, RT-qPCR, and western blotting, respectively. A KDM1A overexpression plasmid, catalytically inactive KDM1A overexpression plasmid, or short hairpin RNA (shRNA) plasmid was transfected into T24 cells to evaluate their effects. A xenograft tumor model was used to further confirm the anti-tumor effect of salinomycin. Our results showed that salinomycin significantly inhibited cell proliferation, promoted apoptosis, increased MDA levels, decreased SOD levels, induced H3K4 histone methylation, and suppressed KDM1A expression. Furthermore, the sh-KDM1A plasmid had effects similar to those of salinomycin and also activated the unfolded protein response pathway. The KDM1A overexpression plasmid had effects opposite to those of the sh-KDM1A plasmid, and the catalytically inactive KDM1A overexpression plasmid had no effect. Meanwhile, KDM1A overexpression reversed the effects of salinomycin on T24 cells. Finally, in vivo experiments confirmed the above results. In the salinomycin treatment group, tumor growth and KDM1A expression were suppressed and cell apoptosis and UPR were induced, while treatment with the KDM1A overexpression plasmid produced the opposite effects. Collectively, our study revealed that salinomycin suppressed T24 cell proliferation and promoted oxidative stress and apoptosis by regulating KDM1A and the UPR pathway. Supplementary Information: The online version contains supplementary material available at 10.1007/s10616-022-00546-y.

Relations between left atrial appendage contrast retention and thromboembolic risk in patients with atrial fibrillation.

Left atrial appendage (LAA), a blind pouch, accounts for more than 90% of the source of cardiac thrombus formation. Contrast retention (CR) in the LAA has been frequently observed during left atrial appendage occlusion (LAAO) procedures, especially in patients with stroke history. This study was designed to assess the relations between LAA contrast retention and thrombogenesis risk of the LAA in patients with non-valvular atrial fibrillation. A total of 132 consecutive patients who underwent LAAO were enrolled. The data collected from computed tomography (CT), transthoracic echocardiography (TTE), transesophageal echocardiography (TEE) and blood samples were analyzed. Univariate and multivariate logistic regression models were constructed to assess the association between CR, left atrial appendage thrombus (LAAT) and other factors. Contrast retention was observed in 33 patients, accounting for 25% of the population. Compared to the non-CR group, patients in the CR group had a larger left atrium anteroposterior diameter (49.64 ± 11.57 vs. 42.42 ± 7.04, P = 0.002), higher CHADS2 (3.88 ± 0.99 vs. 2.97 ± 1.35, P = 0.001) and CHA2DS2-VASc scores (5.79 ± 1.14 vs. 4.89 ± 1.56, P = 0.003), a higher rate of prior stroke (90.9% vs. 66.7%, P = 0.007), more LAA lobes (3.13 ± 1.18 vs. 2.64 ± 1.12, P = 0.038), and a higher prevalence of LAAT (63.6% vs. 13.1%, P < 0.001). After having adjusted the logistic model, only contrast retention, LAA cauliflower morphology and left ventricular ejection fraction (LVEF) were independently associated with LAAT. Patients with LAA contrast retention have a higher risk of left atrial appendage thrombosis. Contrast retention may be a cardiac factor strongly associated with cardiogenic stroke.

RNA and liquid-liquid phase separation.

Liquid-Liquid Phase Separation (LLPS) is a biological phenomenon that refers to the components of similar properties form droplets condensate in cells. These droplets play an important role in maintaining the stability of order in cells. In the studies of phase separation, weak multivalent interactions between proteins have always been the focus of attentions. With the deepening research of phase separation, more and more evidences show that RNA, especially long noncoding RNA (lncRNA), also plays an important regulatory role in the phase separation. We summarized recent researches between phase separation and RNA, and focused on the function of non-coding RNA (ncRNA) in the process of phase separation. In fact, phase separation and RNA have a two-way regulation relationship. Noncoding RNA usually recruits proteins as molecular scaffolds to drive phase separation. On the other hand, phase separation is also involved in RNA transcription, transport, metabolism and other processes.

Mobile health technology-supported atrial fibrillation screening and integrated care: A report from the mAFA-II trial Long-term Extension Cohort.

BACKGROUND: In the mobile Atrial Fibrillation App (mAFA)-II trial, the use of mobile health (mHealth) technology, incorporating AF screening and integrated management strategy, was associated with improved short-term clinical outcomes. The aim of this study was to report adherence/persistence and long term (≥1 year) clinical outcomes of the mAFA-II trial, with mHealth-supported optimised stroke prevention, symptom control and comorbidity management. METHODS: We studied an adult population screened for AF, where identified patients could enter a structured program of holistic and integrated care based on the ABC (Atrial fibrillation Better Care) pathway using mHealth with a mAFA intervention. In this cluster randomised trial, comparing mHeath intervention to usual care, the primary composite outcome was 'stroke/thromboembolism, all-cause death and rehospitalization'. RESULTS: The 1261 subjects (mean age 67.0 years, 38.0% female) who were followed up over one year (mean follow-up 687 (standard deviation, SD 191) days) in the intervention arm, had a lower risk of the composite outcome of 'ischaemic stroke/systemic thromboembolism, death, and rehospitalization' (hazard ratio, HR 0.18, 95% confidence interval, CI: 0.13-0.25, P < 0.001), compared to usual care (1212 subjects, mean age 70.1 years, 42.1% female). Of 842 patients using their smart devices for 'Better symptom management', 70.8% had good management adherence (monitoring time/follow-up since initial monitoring ≥ 70%), with the persistence of use of 91.7%. CONCLUSION: Amongst AF patients with long term use (≥1 year) of mHealth technology for optimising stroke prevention, symptom control and comorbidity management, adherence/persistence was good and associated with a reduction in adverse clinical outcomes.

Amplitude reduction of autonomic nerve function is correlated with ablation lesion quality in patients with paroxysmal atrial fibrillation.

OBJECTIVE: Circumferential pulmonary vein isolation (CPVI) is a common procedure that is performed on patients with atrial fibrillation (AF). However, AF may recur in some patients after treatment. This study assesses the association between autonomic modulation and late recurrence after CPVI and between autonomic modulation and ablation lesion quality. METHODS: We prospectively enrolled 72 patients with paroxysmal AF who underwent CPVI from January 2017 to January 2018. Pre- and post-ablation 24 h electrocardiograms were performed to document heart rate variability (HRV), which represents cardiac autonomic function. The intraablation force-time integral (FTI) was used to indicate the extent of ablation injury. Patients were followed up for 12 months after the procedure and cases of AF recurrence were recorded. RESULTS: Changes in HRV decreased after the procedure, which was correlated with FTI (ΔSDNN: r = -0.26, P = 0.03; ΔrMMSD: r = -0.28, P = 0.02; ΔlnHF: r = -0.22, P = 0.04; ΔLnLF: r = -0.29, P = 0.01). Patients without AF recurrence had more pronounced ΔLF (-21.84 ± 33.21% vs. -8.68 ± 34.59%, P = 0.01) and ΔHF (-17.26 ± 16.61% vs. -1.28 ± 9.81%, P = 0.01) than patients with recurrence. Multivariate regression analysis showed that both ΔLF (HR: 1.07, P = 0.04) and ΔHF (HR: 1.11, P = 0.01) were associated with AF recurrence. After adjusting for FTI, ΔLF was no longer associated with AF recurrence (HR: 1.05, P = 0.10). ΔHF remained associated with AF recurrence (HR: 1.08, P = 0.03), but the correlation coefficient was decreased (HR: 1.08, P = 0.03). CONCLUSION: Decreased autonomic nerve function is a valid predictor of AF recurrence and is indicated by the extent of ablation injury, which is independently associated with AF recurrence after CPVI.

LINC00473 mediates cyclin D1 expression through a balance between activation and repression signals in breast cancer cells.

Long noncoding RNAs (lncRNAs) are critical regulators in tumorigenesis. However, their roles in breast cancer remain unclear. Here, we found that lncRNA LINC00473 is significantly upregulated in breast cancer cells. Loss- or gain-of-function experiments show that LINC00473 promotes cell proliferation. Mechanistically, LINC00473 is required for the activation of cyclin D1 (CCND1) expression through recruitment of phosphorylated CREB and histone acetylation to the CCND1 promoter. Interestingly, we found that LINC00473 is also required for maintaining the expression levels of the noncoding RNACCND1 s and recruiting corepressor FUS to the CCND1 promoter. Altogether, the activation effect of LINC00473 on CCND1 is a net effect of two antagonistic regulatory pathways. Our finding provides a novel lncRNA-mediated precise transcriptional control of CCND1.

Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry: protocol for a prospective, observational nationwide cohort study.

INTRODUCTION: Atrial fibrillation (AF) is a worldwide healthcare burden that is associated with the ageing population. Elderly patients with AF with multiple comorbidities usually present with a high risk of thromboembolism and bleeding. Limited prospective data are available from Asian cohorts on the epidemiology and complications of AF. The present prospective cohort study aims to explore contemporary antithrombotic strategies among the elderly Chinese population in the new era of non-vitamin K antagonist oral anticoagulants and to compare the clinical characteristics and outcomes between Chinese and European AF populations. METHODS AND ANALYSIS: The Optimal Thromboprophylaxis in Elderly Chinese Patients with Atrial Fibrillation (ChiOTEAF) registry will recruit 5000 patients with AF over 65 years of age in China. AF-related risks, including stroke/systemic thromboembolism and bleeding outcomes, will be assessed. Medical history, risk factors, demographic information and management will be collected at baseline, and clinical events during 1 year follow-up will be recorded. Follow-up will be conducted for at least 1 year and then annually thereafter. As our registry has a common protocol to the European Society of Cardiology EURObservational Research Programme AF general registry programme, preplanned analyses comparing the clinical profiles and outcomes will be performed. The ChiOTEAF registry offers an opportunity to provide a better understanding of the clinical profiles and adverse outcomes of patients with AF in China and allow for comparisons with a contemporary European population. ETHICS AND DISSEMINATION: Ethics approval was granted by the Central Medical Ethic Committee of Chinese PLA General Hospital (approval no S2014-065-01). The (inter)national research presentations, peer-reviewed publications and media coverage of the research will be sued for dissemination of the results.

Surface electrocardiography characteristics and radiofrequency catheter ablation of idiopathic ventricular arrhythmias originating from the left infero-septal papillary muscles: differences from those originating from the left posterior fascicle.

Aims: Distinguishing between ventricular arrhythmias originating from the left ventricular infero-septal papillary muscles (PM) and those from the left posterior fascicle (LPF) by surface electrocardiography (ECG) is very difficult. This study aimed to report the ECG characteristics and radiofrequency catheter ablation of PM and LPF ventricular arrhythmias. Methods and results: A total of 127 patients underwent catheter ablation of idiopathic ventricular arrhythmias originating from the LPF (n = 106; 85 males; 10-70 years) or PM (n = 21; 14 males; 4-68 years) were studied. A three-dimensional electroanatomic system (3D-EAS) was used to aid ablation. PM ventricular arrhythmias had a longer QRS duration (154.4 ± 18.0 vs. 119.7 ± 12.6 ms, P < 0.001) than LPF ventricular arrhythmias. All 7 ventricular arrhythmias with QRS duration >160 ms originated from the PM, whereas all 87 ventricular arrhythmias with QRS duration <130 ms arose from the LPF. In 33 ventricular arrhythmias with QRS 130-160 ms, all 13 with Vi/Vt ≤ 0.85 originated from the PM, and 19 of 20 with Vi/Vt > 0.85 arose from the LPF. Of the 8 PM ventricular arrhythmias patients whose initial ablation was undertaken using a non-irrigated 4 mm-tip catheter, 1 failed and 6 recurred. However, of the remaining 13 ones using an irrigated catheter and the 3D-EAS, all succeeded and 2 recurred. No complications were noted in any patient. Conclusion: PM ventricular arrhythmias could be identified from LPF ventricular arrhythmias by calculation of QRS duration combined with Vi/Vt using ECG.

Early Repolarization Pattern Predicts the Increased Risk of Ventricular Arrhythmias in Patients With Acute Anterior ST-Segment Elevation Myocardial Infarction　- A Propensity Analysis.

BACKGROUND: The association between the early repolarization pattern (ERP) and ventricular arrhythmias in patients with ST-segment elevation myocardial infarction (STEMI) remains uncertain. We hypothesized that ERP predicts the risk of sustained ventricular tachycardia (VT)/ventricular fibrillation (VF) during the acute phase of anterior STEMI.Methods and Results:We enrolled 1,460 consecutive patients with acute anterior STEMI. We identified an ERP-positive group and a 1:6 propensity-matched ERP-negative group of 183 and 471, respectively. Comparisons of sustained VT/VF, heart failure, major adverse cardiovascular events and all-cause death were based on Kaplan-Meier survival analysis and multivariable Cox proportional hazards regression with adjustment for unmatched confounding factors. In our full matching propensity score cohorts, there were 8 out of 28 variables not matching between the 2 groups. The Kaplan-Meier curves showed ERP increased the risk of sustained VT/VF in 30 days (log-rank test P=0.00065). Adjusted for baseline unmatched confounding risk, the Cox hazards regression analysis showed sustained VT/VF was associated with the present of ERP (hazard ratio=2.915, 95% CI: 1.520-5.588, P=0.001). CONCLUSIONS: In a propensity score-adjusted cohort the presence of ERP had a multivariable-adjusted association with increased risk of sustained VT/VF in patients with anterior STEMI in the early 30 days.

Febuxostat attenuates paroxysmal atrial fibrillation-induced regional endothelial dysfunction.

BACKGROUND: Paroxysmal atrial fibrillation (PAF) can increase thrombogenesis risk, especially in the left atrium (LA). The exact mechanism is still unclear. OBJECTIVE: We assessed the effects of PAF on endothelial function, and investigated if febuxostat (FX) can attenuate endothelial dysfunction by inhibition of xanthine oxidase (XO). MATERIALS AND METHODS: Eighteen male New Zealand white rabbits were divided randomly into sham-operated (S), PAF (P) or FX+pacing (FP) groups. Group P and group FP received rapid atrial pacing (RAP). Group FP was administered febuxostat (FX) for 7days before RAP. Post-procedure, blood samples were collected from the LA, right atrium (RA) and peripheral circulation. Tissues from the LA and RA were obtained. Endothelial dysfunction (thrombomodulin [TM], von Willebrand factor [VWF], asymmetric dimethylarginine [ADMA]), and indirect thrombin generation (thrombin-antithrombin complex [TAT], prothrombin fragment 1+2 [F1.2]) and oxidative stress in atrial tissue (xanthine oxidase [XO], superoxide dismutase [SOD], malondialdehyde [MDA]) were measured using an Enzyme-linked immunosorbent assay. Atrial endothelial expression of TM and VWF was measured by histology/western blotting. RESULTS AND CONCLUSIONS: Endothelial dysfunction (TM, VWF, ADMA), TAT generation and oxidative stress (XO, SOD, MDA) in group P were more significant compared with that in group S (p<0.05, respectively). In group P, all of these changes occurred to a greater extent in the LA compared with those in the RA or peripheral circulation. In group FP, FX attenuated endothelial dysfunction and reduced TAT levels by inhibition of XO-mediated oxidative stress. PAF can lead to endothelial dysfunction and TAT generation by XO-mediated oxidative stress. The LA is more susceptible to these effects. FX can attenuate these changes by inhibition XO and XO-mediated oxidative stress.

Radiofrequency ablation of metastatic chondrosarcoma-associated refractory ventricular tachycardia originating from the right ventricular outflow tract: A case report and literature review.

Ventricular tachycardia (VT) and premature contraction originating from the right ventricular outflow tract (RVOT) usually appear in healthy individuals. Radiofrequency ablation (RFA) is highly effective at resolving this type of arrhythmia. Refractory VT of RVOT is uncommon and occasionally results from cardiac metastasis of extraskeletal mesenchymal chondrosarcomas (ESMC). ESMC is a rare malignant tumor arising from soft tissues. The current study presents the case of a 25-year-old male with severe VT arising from RVOT due to metastasis of an ESMC that originally occurred in the retroperitoneum. The diagnosis was confirmed following echocardiography and cardiac magnetic resonance. VT was eventually eliminated by RFA, and during the 8-month follow-up period the patient did not complain of any palpitations. Holter monitoring confirmed the absence of recurrence.

Assessing bleeding risk in 4824 Asian patients with atrial fibrillation: The Beijing PLA Hospital Atrial Fibrillation Project.

The risks of major bleeding and intracranial hemorrhage (ICH) are higher in Asian patients with atrial fibrillation (AF) compared to non-Asians. We aimed to investigate risk factors for bleeding, and validate the predictive value of available bleeding risk scores (mOBRI, HEMORR2HAGES, Shireman, HAS-BLED, ATRIA and ORBIT) in a large cohort of Chinese inpatients with AF. Using hospital electronic medical databases, we identified 4824 AF patients (mean age 67 years; 34.9% female) from January 1, 1995 to May 30, 2015, with median (interquartile) in-hospital days of 10 (7-16) days. On multivariate analysis, prior bleeds, vascular disease, anemia, prior stroke, and liver dysfunction were independent risk factors of major bleeding (all p < 0.05). C-statistics (95%CI) of the HAS-BLED score were 0.72 (0.65-0.79) for major bleeding events and 0.83 (0.75-0.91) for ICH (all p < 0.001). Compared to other risk scores, the HAS-BLED score was significantly better in predicting major bleeding events (Delong test, all P < 0.05, apart from mOBRI, HEMORR2HAGES) and ICH (all p < 0.05), and additionally, resulted in a net reclassification improvement (NRI) of 17.1-65.5% in predicting major bleeding events and 29.5-67.3% in predicting ICH (all p < 0.05). We conclude that the HAS-BLED score had the best predictive and discriminatory ability for major bleeding and ICH in an Asian/Chinese AF population.

[Predict value of time to peak of systolic velocity derived from velocity vector imaging on cardiac resynchronization therapy response in refractory heart failure patients].

OBJECTIVE: To investigate the impact of cardiac resynchronization therapy (CRT) on left ventricular systolic function evaluated by velocity vector imaging (VVI) in refractory heart failure patients and the predictive value of VVI on CRT responses. METHODS: This study included 38 patients with medically refractory heart failure (HF) patients underwent CRT in our department from May 2007 to April 2011. Left ventricular long axis dyssynchrony indexes including time to peak of systolic velocity (Ts max-min), standard deviation of the time to peak of systolic velocity (Ts-SD) before and at 3-6 months post CRT. CRT response was defined as 15% decrease in left ventricular end-systolic volume. ROC curve and the area under the curve (AUC) were calculated. RESULTS: Twenty-four patients were defined as responder. No significant difference was observed between responders and non-responders in medical therapy. When using Ts max-min to predict response, the AUC of ROC curves was 0.76 ± 0.07. The sensitivity and specifity was 70.8% and 77.8% respectively with Ts max-min ≥ 124.0 ms. When using Ts-SD to predict response, the AUC of ROC curves was 0.82 ± 0.07. The sensitivity and specifity was 79.2% and 71.2% respectively with Ts-SD ≥ 40.5. CONCLUSION: Ts-SD is a useful index to predict CRT response in refractory HF patients.

Is dabigatran efficacy enough to prevent stroke in atrial fibrillation patient with high CHADS2 score during peri-procedural catheter radiofrequency ablation? A case report with literature review.

Atrial fibrillation (AF) is a major cause of thromboembolic (TE) events including stroke and transient ischemic attacks, catheter radiofrequency ablation (CA) has been demonstrated to effectively eliminate AF in majority of patients. During the peri-procedural CA of AF, dabigatran, a reversible direct thrombin inhibitor, has been proved as safe and efficacy as warfarin in the prevention of thromboembolic complication. However, for patients with CHADS2 score ≥3, sometimes dabigatran may not be an ideal substitute of warfarin. The current study presents delayed stroke occurred in a middle-aged AF patient with high CHADS2 score who had undergone successful CA of AF being on dabigatran, trans esophageal echocardiogram (TEE) detected a clot in the left atrium appendage (LAA) and magnetic resonance image (MRI) indicated stroke of left basal ganglia, therefore anticoagulant was switched to warfarin with well controlled international normalization ratio (INR) ranging from 2.0-3.0 and the patient eventually recovered without any TE events during the subsequent follow-up.

Renal denervation suppresses atrial fibrillation in a model of renal impairment.

BACKGROUND: A close association exists between renal impairment (RI) and atrial fibrillation (AF) occurrence. Increased activity of the sympathetic nervous system (SNS) may contribute to the development of AF associated with RI. Renal denervation (RDN) decreases central sympathetic activity. OBJECTIVE: The main objective of the study was to explore the effects of RDN on AF occurrence and its possible mechanisms in beagles with RI. METHODS: Unilateral RI was induced in beagles by embolization of small branches of the renal artery in the right kidney using gelatin sponge granules in Model (n = 6) and RDN group (n = 6). The Sham group (n = 6) underwent the same procedure, except for embolization. Then animals in RDN group underwent radiofrequency ablation of the renal sympathetic nerve. Cardiac electrophysiological parameters, blood pressure, left ventricular end-diastolic pressure, and AF inducibility were investigated. The activity of the SNS, renin-angiotensin-aldosterone system (RAAS), inflammation and atrial interstitial fibrosis were measured. RESULTS: Embolization of small branches of the renal artery in the right kidney led to ischemic RI. Heart rate, P wave duration and BP were increased by RI, which were prevented or attenuated by RDN. Atrial effective refractory period was shortened and AF inducibility was increased by RI, which were prevented by RDN. Antegrade Wenckebach point was shortened, atrial and ventricular rates during AF were increased by RI, which were attenuated or prevented by RDN. Levels of norepinephrine, renin and aldosterone in plasma, norepinephrine, angiotensin II, aldosterone, interleukin-6 and high sensitivity C-reactive protein in atrial tissue were elevated, and atrial interstitial fibrosis was enhanced by RI, which were attenuated by RDN. CONCLUSIONS: RDN significantly reduced AF inducibility, prevented the atrial electrophysiological changes in a model of RI by combined reduction of sympathetic drive and RAAS activity, and inhibition of inflammation activity and fibrotic pathway in atrial tissue.

Electrophysiological characteristics of paroxysmal atrial fibrillation originating from superior vena cava: a clinical analysis of 30 cases.

To analyze characteristics of electrocardiogram (ECG), electrophysiological intracardiac mapping and radiofrequency ablation (RF) of paroxysmal atrial fibrillation (PAF) originating from superior vena cava (SVC), aiming to investigate electrophysiological characteristics of PAF with SVC origin. Clinical data of 30 subjects (18 men and 12 women, aged, 58.6 ± 15.5 years) with PAF of SVC origin were retrospectively analyzed; All patients underwent RF during 2006.9-2012.7. ECG of AF and atrial premature contractions (APCs), procedure and fluoroscopic time, numbers of ablation sites within SVC, complications and success rate were studied. Compared with P wave of sinus rhythm (SR), APCs of SVC origin exhibited higher amplitude in lead II (0.23 ± 0.11 vs. 0.15 ± 0.06 mv), III (0.19 ± 0.09 vs. 0.13 ± 0.08 mv), AVF (0.21 ± 0.13 vs. 0.14 ± 0.10 mv), V2 (0.24 ± 0.07 vs. 0.15 ± 0.09 mv) and V3 (0.21 ± 0.09 vs. 0.12 ± 0.05 mv) (P < 0.05), as well as more biphasic polarity in lead V1 (80.0% vs. 26.6%, P < 0.05) and isoelectric in AVL (60.0% vs. 6.7%, P < 0.05). In terms of left pulmonary vein (LPV) and right pulmonary vein (RPV) electrical isolation, procedure time (14.3 ± 11.5 vs. 33.7 ± 14.2, 28.1 ± 6.8 min, P < 0.05), fluoroscopic time (9.6 ± 3.8 vs. 21.1 ± 9.3, 19.4 ± 9.7 min, P < 0.05), ablation sites (11.2 ± 3.1 vs. 37.1 ± 13.7, 31.4 ± 10.4 points, P < 0.05) of SVC isolation (SVCI) remarkably decreased compared with that of mean LPV and RPV. After the procedure, 9 patients still presented paroxymal rapid firing within the SVC in the setting of SR restoration, 2 patients developed paroxysmal atrial flutter within 1 month after completion of ablation and were controlled by antiarrhythmic drugs. The APCs and AF of SVC origin manifested distinctive ECG features, which could be helpful to distinguish SVC from other foci before ablation, the completion of SVCI required shorter procedure and fluoroscopic time, as well as less ablation points, and meanwhile, the success rate was high with less complication.

Establishment of a model of renal impairment with mild renal insufficiency associated with atrial fibrillation in canines.

BACKGROUND: Chronic kidney disease and occurrence of atrial fibrillation (AF) are closely related. No studies have examined whether renal impairment (RI) without severe renal dysfunction is associated with the occurrence of AF. METHODS: Unilateral RI with mild renal insufficiency was induced in beagles by embolization of small branches of the renal artery in the left kidney for 2 weeks using gelatin sponge granules in the model group (n = 5). The sham group (n = 5) underwent the same procedure, except for embolization. Parameters associated with RI and renal function were tested, cardiac electrophysiological parameters, blood pressure, left ventricular pressure, and AF vulnerability were investigated. The activity of the sympathetic nervous system, renin-angiotensin-aldosterone system, inflammation, and oxidative stress were measured. Histological studies associated with atrial interstitial fibrosis were performed. RESULTS: Embolization of small branches of the renal artery in the left kidney led to ischemic RI with mild renal insufficiency. The following changes occurred after embolization. Heart rate and P wave duration were increased. Blood pressure and left ventricular systolic pressure were elevated. The atrial effective refractory period and antegrade Wenckebach point were shortened. Episodes and duration of AF, as well as atrial and ventricular rate during AF were increased in the model group. Plasma levels of norepinephrine, renin, and aldosterone were increased, angiotensin II and aldosterone levels in atrial tissue were elevated, and atrial interstitial fibrosis was enhanced after 2 weeks of embolization in the model group. CONCLUSIONS: We successfully established a model of RI with mild renal insufficiency in a large animal. We found that RI with mild renal insufficiency was associated with AF in this model.