Higher Cumulative Blood Pressure in Midlife Predicts an Increased Risk of Atrial Fibrillation: Evidence From the Atherosclerosis Risk in Communities Study.

BACKGROUND: Elevated blood pressure (BP) is reportedly associated with an increased risk of atrial fibrillation (AF). However, the association between cumulative BP exposure in midlife and incident AF in mid-to-late life remains unclear. METHODS AND RESULTS: Participants enrolled in the ARIC (Atherosclerosis Risk in Communities) study with 4 consecutive BP measurements and no prevalent AF at baseline were included. Cumulative BP was calculated as the area under the curve from visit 1 to visit 4. Incident AF was identified by study visit ECGs, hospital discharge codes, or death certificates. A total of 9892 participants were included (44.6% men and mean age 62.9±5.7 years at visit 4) with 1550 (15.7%) individuals who developed new-onset AF during an average follow-up of 15.4 years. The incidence rates of AF per 1000 person-years across the 4 quartiles of cumulative systolic BP were 7.9, 9.2, 12.5, and 16.9, respectively. After multivariable adjustment, the hazard ratios for incident AF among participants in the highest quartile of cumulative systolic BP, pulse pressure, and mean arterial pressure were 1.48 (95% CI, 1.27-1.72), 1.81 (95% CI, 1.53-2.13), and 1.22 (95% CI, 1.05-1.41), respectively, compared with those in the lowest quartile. The addition of cumulative systolic BP or pulse pressure slightly improved the ability to predict new-onset AF. CONCLUSIONS: Higher exposure to cumulative systolic BP, pulse pressure, and mean arterial pressure was significantly associated with increased risk of incident AF.

Role of Ideal Cardiovascular Health Metrics in Reducing Risk of Incident Arrhythmias.

AIMS: Cardiovascular health (CVH) has been proved to reduce cardiovascular disease burden and mortality, but data are lacking regarding cardiac arrhythmias. The aim of this study was to assess the association between CVH metrics and atrial fibrillation/flutter (AF), ventricular arrhythmias and bradyarrhythmias. METHODS AND RESULTS: This study analyzed data from the ARIC (Atherosclerosis Risk in Communities) cohort, with participants recruited from four different communities across the United States. CVH metrics were scored at baseline (1987 to 1989) following the AHA's recommendations and categorized as poor, intermediate, or ideal. Arrhythmia episodes were diagnosed by ICD-9 code. Adjusted associations were estimated using Cox models and event rates and population attributable fractions were calculated by CVH metrics category. The study population consisted of 13078 participants, with 2548 AF, 1363 ventricular arrhythmias, and 706 bradyarrhythmias occurred. The adjusted hazard ratios (HRs) for ideal (vs. poor) CVH metrics were 0.59 (95% confidence interval [CI]: 0.50 to 0.69) for AF, 0.38 (95% CI: 0.28 to 0.51) for ventricular arrhythmias, and 0.70 (95% CI: 0.51 to 0.97) for bradyarrhythmia. The risk of incident arrhythmias decreased steadily as the CVH metrics improved from 0 to 14 scores. The adjusted population attributable fractions were calculated to be 29.9% for AF, 54.4% for ventricular arrhythmias, and 21.9% for bradyarrhythmia, respectively. The association between CVH metrics and incident arrhythmias was also seen in people who remained free of coronary heart disease over the follow-up. CONCLUSION: Achieving ideal CVH metrics recommendations by AHA in midlife was associated with a lower risk of incident arrhythmias later in life.

(1) Intermediate and ideal levels of cardiovascular health metrics are associated with a markedly reduced risk of developing incident arrhythmias, including atrial fibrillation/flutter, ventricular arrhythmias and bradyarrhythmia, independent of coronary heart disease. (2) A majority of incident arrhythmias could be prevented if the risk profile of the entire population were optimized. (3) These findings emphasize the significance of public health policies that improve cardiovascular health to reduce the social and economic burden of arrhythmias.

Secular trends of health care resource utilization and costs between Brugada syndrome and congenital long QT syndrome: A territory-wide study.

BACKGROUND: Health care resource utilization (HCRU) and costs are important metrics of health care burden, but they have rarely been explored in the setting of cardiac ion channelopathies. HYPOTHESIS: This study tested the hypothesis that attendance-related HCRUs and costs differed between patients with Brugada syndrome (BrS) and congenital long QT syndrome (LQTS). METHODS: This was a retrospective cohort study of consecutive BrS and LQTS patients at public hospitals or clinics in Hong Kong, China. HCRUs and costs (in USD) for Accident and Emergency (A&E), inpatient, general outpatient and specialist outpatient attendances were analyzed between 2001 and 2019 at the cohort level. Comparisons were made using incidence rate ratios (IRRs [95% confidence intervals]). RESULTS: Over the 19-year period, 516 BrS (median age of initial presentation: 51 [interquartile range: 38-61] years, 92% male) and 134 LQTS (median age of initial presentation: 21 [9-44] years, 32% male) patients were included. Compared to LQTS patients, BrS patients had lower total costs (2 008 126 [2 007 622-2 008 629] vs. 2 343 864 [2 342 828-2 344 900]; IRR: 0.857 [0.855-0.858]), higher costs for A&E attendances (83 113 [83 048-83 177] vs. 70 604 [70 487-70 721]; IRR: 1.177 [1.165-1.189]) and general outpatient services (2,176 [2,166-2,187] vs. 921 [908-935]; IRR: 2.363 [2.187-2.552]), but lower costs for inpatient stay (1 391 624 [1 391 359-1 391 889] vs. 1 713 742 [1 713 166-1 714 319]; IRR: 0.812 [0.810-0.814]) and lower costs for specialist outpatient services (531 213 [531 049-531 376] vs. 558 597 [558268-558926]; IRR: 0.951 [0.947-0.9550]). CONCLUSIONS: Overall, BrS patients consume 14% less health care resources compared to LQTS patients in terms of attendance costs. BrS patients require more A&E and general outpatient services, but less inpatient and specialist outpatient services than LQTS patients.

Applicability of Zipf's Law in Traditional Chinese Medicine Prescriptions.

Objective Traditional Chinese medicine (TCM) prescriptions have been used to cure diseases in China for thousands of years, in which many TCM herbs have no definite common quantity. Some key TCM herbs are commonly used and thus deserve in-depth investigations based on a more acceptable classification method. This study analyzes whether TCM prescriptions follow Zipf's law and attempts to obtain the thresholds of key TCM herbs based on the application of Zipf's law. Methods A total of 84,418 TCM prescriptions were collected and standardized. We tested whether Zipf's law and Zipf's distribution fit the Chinese herb distributions. A linear fitting experiment was performed to verify the relationship between the frequency distribution and frequency of TCM herbs. Results The distribution of TCM herbs in TCM prescriptions conformed to Zipf's law. Accordingly, the thresholds were obtained for the key TCM herbs. Conclusion The distribution of TCM herbs in TCM prescriptions follows Zipf's law.

Atrial fibrillation mechanisms before and after pulmonary vein isolation characterized by noncontact charge density mapping.

BACKGROUND: The interaction of the pulmonary vein (PV) and putative nonpulmonary triggers of atrial fibrillation (AF) remains unclear and has yet to translate into patient-tailored ablation strategies. OBJECTIVE: The purpose of this study was to use noncontact mapping to detail the global conduction patterns in paroxysmal and persistent AF and how they are modified during PV ablation. METHODS: Forty patients during AF ablation underwent mapping using a noncontact catheter (AcQMap, Acutus Medical, Inc., Carlsbad, CA) before and after PV isolation (PVI). Propagation history maps were analyzed postprocedure for each patient to categorize conduction patterns into focal, organized reentrant, and disorganized patterns (F-Patterns, O-Patterns, and D-Patterns, respectively). RESULTS: Activation patterns identified by using a noncontact mapping system can be subclassified from 3 main patterns into subtypes (macroreentrant and localized reentrant [MR and LR] subtypes and disorganized 1 and disorganized 2 [D1 and D2] subtypes). Persistent AF demonstrated more D-Patterns and less O-Patterns and F-Patterns than did paroxysmal AF. In addition, patients with PAF inducible after PVI demonstrated a higher region number and higher prevalence of MR subtypes than did those noninducible. PVs remained the critical region and included almost one-third of all patterns across any AF types. PVI was effective to eliminate PV-related functional phenotypes and affected recurrence with other patterns. CONCLUSION: Activation patterns identified using AcQMap can be classified into 3 main patterns (F-Patterns, O-Patterns, and D-Patterns) as well as subtypes (MR and LR subtypes and D1 and D2 subtypes). PerAF was different from PAF in demonstrating a higher region number and higher prevalence of D-Patterns but a lower region number and lower prevalence of O-Patterns and F-Patterns.

Clinical Characteristics and Long-Term Prognosis of Elderly Valvular Heart Disease Patients with Diabetes Mellitus: Five-Year Experience from a Single-Center Study of Southern China.

BACKGROUND: Diabetes mellitus (DM) is a prognostic marker in elderly patients with cardiovascular diseases, but its predictive value in elderly valvular heart disease (VHD) patients is unclear. This study aimed to investigate the effect of DM on the long-term outcome of elderly VHD patients. METHODS: This single-center, observational study enrolled patients aged 65 and older consecutively with confirmed VHD using echocardiography. Patients, divided into the DM group and non-DM group, were followed up for major adverse cardiac and cerebrovascular events (MACCEs), including all-cause death, ischemic stroke, and heart failure rehospitalization. RESULTS: Our study consisted of 532 patients over a median follow-up of 52.9 months. Compared with the non-DM group (n = 377), the DM group (n = 155) had higher incidences of ischemic stroke (25.2% vs. 13.5%, P=0.001), heart failure rehospitalization (37.4% vs. 20.7%, P < 0.001), and MACCEs (60.0% vs. 35.8%, P < 0.001). After adjustment of confounders by the multivariable cox regression, DM appeared as an independent predictor for MACCEs (adjusted hazard ratio, aHR: 1.88; 95% confidence interval 1.42-2.48; P < 0.001). In the subgroup analysis of VHD etiology and functional style, conversely, DM was a protective factor for MACCEs in the patients with rheumatic VHD compared with those without rheumatic VHD (aHR: 0.43 vs. 2.27, P=0.004). CONCLUSIONS: DM was an independent predictor for ischemic stroke and heart failure rehospitalization in elderly VHD patients undergoing conservative treatment.

Correction: Effect of Physician-Pharmacist Participation in the Management of Ambulatory Cancer Pain Through a Digital Health Platform: Randomized Controlled Trial.

[This corrects the article DOI: 10.2196/24555.].

[Effect of Nrf2/HO-1 signaling pathway in intestinal protection by Sishen Pills against ulcerative colitis in mice].

The present study aimed to explore the effect of nuclear factor erythroid 2 related factor 2(Nrf2)/heme oxygenase-1(HO-1) signaling pathway in intestinal protection by Sishen Pills against ulcerative colitis(UC). After the UC model was induced by 3% dextran sodium sulfate(DSS), experimental animals were randomly divided into control group, model group, salazosulfapyridine(SASP) group, and low-and high-dose Sishen Pills groups. Drug intervention(ig) was performed for seven consecutive days during modeling. On the 7 th day, the mice were euthanized. The body weight and colon length were recorded, and the histopathological changes of the colon were observed by HE staining. Serum interleukin-6(IL-6), tumor necrosis factor-α(TNF-α), total antioxidant capacity(T-AOC), malondialdehyde(MDA), and reactive oxygen species(ROS) were detected by ELISA. The protein and mRNA expression of Nrf2, HO-1, and NADPH quinine oxidoreductase-1(NQO-1) was determined by Western blot and reverse transcription-polymerase chain reaction(RT-PCR). Compared with the normal group, the model group exhibited reduced body weight, colon length, and T-AOC, increased IL-6, TNF-α, MDA, and ROS, and diminished protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. Compared with the model group, the SASP group and high-dose Sishen Pills group showed elevated body weight, colon length, and T-AOC, lowered IL-6, TNF-α, MDA, and ROS levels, and increased protein and mRNA expression of Nrf2, HO-1, and NQO-1 in the colon tissues. As assessed by HE staining, Sishen Pills could improve the pathological changes of the colon. The findings suggested that Sishen Pills could protect the colon against UC induced by 3% DSS. The specific mechanism of action may be related to the anti-inflammatory and anti-oxidative stress effects by the activation of the Nrf2/HO-1 signaling pathway.

Prevalence and modifiable risk factors of degenerative valvular heart disease among elderly population in southern China.

OBJECTIVE: To investigate the prevalence and modifiable risk factors of degenerative valvular heart disease (DVHD) among elderly population in southern China. METHODS: A stratified multistage sampling method was used to recruit subjects. The contents of the survey included the questionnaire, laboratory examination, echocardiography, and other auxiliary examinations. The possible risk factors of DVHD were analyzed by logistic regression analysis. RESULTS: A total of 3538 subjects ≥ 65 years of age were enrolled. One thousand three hundred and seven subjects (36.9%) were diagnosed with DVHD. Degenerative was the most common etiology of VHD. Prevalence of DVHD increased with advancing age. The prevalence of DVHD differed by living region (χ 2 = 45.594, P < 0.001), educational level ( χ 2 = 50.557, P < 0.001), and occupation ( χ 2 = 36.961, P < 0.001). Risk factors associated with DVHD included age (two-fold increased risk for each 10-year increase in age), elevated level C-reactive protein (OR = 1.346, 95% CI: 1.100-1.646), elevated level low density lipoprotein (OR = 1.243, 95% CI: 1.064-1.451), coronary artery disease (OR = 1.651, 95% CI: 1.085-2.513), smoking (OR = 1.341, 95% CI: 1.132-1.589), and hypertension (OR = 1.414, 95% CI: 1.221-1.638). Other significant risk factors included reduced or elevated level red blood cell (OR = 1.347, 95% CI: 1.031-1.761; OR = 1.599, 95% CI: 1.097-2.331; respectively), elevated level platelets (OR = 1.891, 95% CI: 1.118-3.198), elevated level uric acid (OR = 1.282, 95% CI: 1.112-1.479), and stroke (OR: 1.738, 95% CI = 1.085-2.513). CONCLUSIONS: The survey characterized the baseline conditions of DVHD cohort of elderly population in Guangzhou city. The established and emerging risk factors for DVHD may represent challenges and opportunities for therapy.

Effect of Physician-Pharmacist Participation in the Management of Ambulatory Cancer Pain Through a Digital Health Platform: Randomized Controlled Trial.

BACKGROUND: Self-management of ambulatory cancer pain is full of challenges. Motivated by the need for better pain management, we developed a WeChat-supported platform, Medication Housekeeper (MediHK), to enhance communication, optimize outcomes, and promote self-management in the home setting. OBJECTIVE: We conducted a randomized controlled trial to assess whether the joint physician-pharmacist team through MediHK would provide better self-management of ambulatory patients with cancer pain. METHODS: Patients were randomly assigned to either an intervention group or control group. During the 4-week study period, the pharmacist would send 24-hour pain diaries daily, adverse drug reaction (ADR) forms every 3 days, and the Brief Pain Inventory form every 15 days to patients in the intervention group via MediHK. If a patient needed a change in drug/dosage or treatment of an ADR after the comprehensive review, the pharmacist would propose pharmacological interventions to the attending physician, who was then responsible for prescribing or adjusting pain medications. If no adjustments were needed, the pharmacist provided appropriate targeted education based on knowledge deficits. Patients in the control group received conventional care and did not receive reminders to fill out the forms. However, if the control group patients filled out a form via MediHK, the pain management team would review and respond in the same way as for the intervention group. The primary outcomes included pain intensity and pain interference in daily life. Secondary outcomes included patient-reported outcome measures, medication adherence, ADRs, and rehospitalization rates. RESULTS: A total of 100 patients were included, with 51 (51%) in the intervention group and 49 (49%) in the control group. The worst pain scores, least pain scores, and average pain scores in the intervention group and the control group were statistically different, with median values of 4 (IQR 3-7) vs 7 (IQR 6-8; P=.001), 1 (IQR 0-2) vs 2 (IQR 1-3; P=.02), and 2 (IQR 2-4) vs 4 (IQR 3-5; P=.001), respectively, at the end of the study. The pain interference on patients' general activity, mood, relationships with others, and interests was reduced, but the difference was not statistically significant compared with the control group (Ps=.10-.76). The medication adherence rate increased from 43% to 63% in the intervention group, compared with an increase of 33% to 51% in the control group (P<.001). The overall number of ADRs increased at 4 weeks, and more ADRs were monitored in the intervention group (P=.003). Rehospitalization rates were similar between the 2 groups. CONCLUSIONS: The joint physician-pharmacist team operating through MediHK improved pain management. This study supports the feasibility of integrating the internet into the self-management of cancer pain. TRIAL REGISTRATION: Chinese Clinical Trial Registry ChiCTR1900023075; https://www.chictr.org.cn/showproj.aspx?proj=36901.

A phosphatidic acid-binding lncRNA SNHG9 facilitates LATS1 liquid-liquid phase separation to promote oncogenic YAP signaling.

Long noncoding RNAs (lncRNAs) are emerging as a new class of important regulators of signal transduction in tissue homeostasis and cancer development. Liquid-liquid phase separation (LLPS) occurs in a wide range of biological processes, while its role in signal transduction remains largely undeciphered. In this study, we uncovered a lipid-associated lncRNA, small nucleolar RNA host gene 9 (SNHG9) as a tumor-promoting lncRNA driving liquid droplet formation of Large Tumor Suppressor Kinase 1 (LATS1) and inhibiting the Hippo pathway. Mechanistically, SNHG9 and its associated phosphatidic acids (PA) interact with the C-terminal domain of LATS1, promoting LATS1 phase separation and inhibiting LATS1-mediated YAP phosphorylation. Loss of SNHG9 suppresses xenograft breast tumor growth. Clinically, expression of SNHG9 positively correlates with YAP activity and breast cancer progression. Taken together, our results uncover a novel regulatory role of a tumor-promoting lncRNA (i.e., SNHG9) in signal transduction and cancer development by facilitating the LLPS of a signaling kinase (i.e., LATS1).

The impact of post-operative atrial fibrillation on outcomes in coronary artery bypass graft and combined procedures.

BACKGROUND: Post-operative atrial fibrillation (POAF) is a common yet understudied clinical issue after coronary artery bypass graft (CABG) leading to higher mortality rates and stroke. This systematic review and meta-analysis evaluated the rates of adverse outcomes between patients with and without POAF in patients treated with CABG or combined procedures. METHODS: The search period was from the beginning of PubMed and Embase to May 18th, 2020 with no language restrictions. The inclusion criteria were: (1) studies comparing new onset atrial fibrillation before or after revascularization vs. no new onset AF before or after revascularization. The outcomes assessed included all-cause mortality, cardiac death, cerebral vascular accident (CVA), myocardial infarction (MI), repeated revascularization, major adverse cardiac event (MACE), and major adverse cardiac and cerebrovascular events (MACCEs). RESULTS: Of the 7,279 entries screened, 11 studies comprising of 57,384 patients were included. Compared to non-POAF, POAF was significantly associated with higher risk of all-cause mortality (Risk Ratio (RR) = 1.58; 95% Confidence Interval (CI): 1.42-1.76, P < 0.00001) with accompanying high level of heterogeneity ( I 2 = 62%). CONCLUSIONS: Patients with POAF after CABG or combined procedures are at an increased risk of all-cause mortality or CVAs. Therefore, POAF after such procedures should be closely monitored and treated judiciously to minimize risk of further complications. While there are studies on POAF versus no POAF on outcomes, the heterogeneity suggests that further studies are needed.

Interfacial stabilization for inverted perovskite solar cells with long-term stability.

Perovskite solar cells (PSCs) commonly exhibit significant performance degradation due to ion migration through the top charge transport layer and ultimately metal electrode corrosion. Here, we demonstrate an interfacial management strategy using a boron chloride subphthalocyanine (Cl6SubPc)/fullerene electron-transport layer, which not only passivates the interfacial defects in the perovskite, but also suppresses halide diffusion as evidenced by multiple techniques, including visual element mapping by electron energy loss spectroscopy. As a result, we obtain inverted PSCs with an efficiency of 22.0% (21.3% certified), shelf life of 7000 h, T80 of 816 h under damp heat stress (compared to less than 20 h without Cl6SubPc), and initial performance retention of 98% after 2000 h at 80 °C in inert environment, 90% after 2034 h of illumination and maximum power point tracking in ambient for encapsulated devices and 95% after 1272 h outdoor testing ISOS-O-1. Our strategy and results pave a new way to move PSCs forward to their potential commercialization solidly.

Experimental Findings and Clinical-Pathologic Correlation of Radiofrequency Catheter Ablation at the Left Ventricle Para-Hisian Region.

BACKGROUND: Catheter ablation target at the site with large His activation in the left ventricle poses a high risk of atrioventricular (AV) block. We aimed to identify far-field (FF) and near-field (NF) His activation at left upper septum (LUS). METHODS: Three-D mapping of the aortic root and left ventricle was performed in 12 dogs. Two sites located at either the base or apex of the triangle interposed between the hinges of the the noncornary coronary cusp (NCC) - right coronary cusp (RCC) were chosen for a single radiofrequency (RF) application. Bipolar and unipolar pacing with different outputs at both sites was attempted to discern NF and FF His activation. RESULTS: The sites chosen for NF and FF ablation were located at the base and apex of the triangle, which were 8.03 ± 1.18 mm (group 1) and 3.42 ± 0.61 mm (group 2) away from the RCC-NCC junction. Lower A/V ratios were found in group 1. Pacing could not differentiate NF from FF His activation. In group 1, ablation resulted in III degree AV block in all 6 dogs, whereas neither PR prolongation nor AV block occurred in group 2. Pathologic examination of group 1 showed complete/partial necrosis of the His bundle (HB) and left bundle branch in all 6 dogs. In group 2, no necrosis of the HB was seen in the 6/6 dogs. CONCLUSION: Anatomical localization in the triangle of RCC-NCC junction can help differentiate NF from FF His activation.

Development of a novel 7 immune-related genes prognostic model for oral cancer: A study based on TCGA database.

Oral squamous cell carcinoma (OSCC) is an aggressive tumor whose prognosis has little improvement in the last three decades. Various immune-related genes have been suggested as significant roles in the development and progression of malignant cancers. In this study, we acquired and integrated differentially expressed genes of OSCC patients, including immune-related genes and transcription factors (TFs), from The Cancer Genome Atlas (TCGA) database. TF-mediated network was established to exploring the regulatory mechanisms of prognostic immune-related genes. A 7 immune-related genes prognostic model for OSCC was obtained, including CGB8, CTLA4, TNFRSF19, CCL26, NRG1, TPM2 and PLAU, which was further proved to be an independent prognostic indicator after adjusting for other clinical factors. The immune-related genes prognostic index was significantly negatively correlated to the infiltration abundances of B cells (P < 0.05) and CD8+ T cells (P < 0.05). The novel proposed immune-based prognostic model not only provided a promising biomarker and a way to monitor the long-term treatment of OSCC, but also gave a new insight into a potential immunotherapy strategy.

Matrine Inhibits CNS Autoimmunity Through an IFN-ß-Dependent Mechanism.

Matrine (MAT), a quinolizidine alkaloid component derived from the root of Sophora flavescens, suppresses experimental autoimmune encephalomyelitis (EAE), the animal model of multiple sclerosis (MS), by inducing the production of immunomodulatory molecules, e.g., IL-10. In an effort to find the upstream pathway(s) of the mechanism underlying these effects, we have tested certain upregulated immunomodulatory molecules. Among them, we found increased levels of IL-27 and IFN-ß, one of the first-line MS therapies. Indeed, while low levels of IFN-ß production in sera and type I interferon receptor (IFNAR1) expression in spinal cord of saline-treated control EAE mice were detected, they were significantly increased after MAT treatment. Increased numbers of CD11b+IFN-ß+ microglia/infiltrating macrophages were observed in the CNS of MAT-treated mice. The key role of IFN-ß induction in the suppressive effect of MAT on EAE was further verified by administration of anti-IFN-ß neutralizing antibody, which largely reversed the therapeutic effect of MAT. Further, we found that, while MAT treatment induced production of IL-27 and IL-10 by CNS microglia/macrophages, this effect was significantly reduced by IFN-ß neutralizing antibody. Finally, the role of IFN-ß in MAT-induced IL-27 and IL-10 production was further confirmed in human monocytes in vitro. Together, our study demonstrates that MAT exerts its therapeutic effect in EAE through an IFN-ß/IL-27/IL-10 pathway, and is likely a novel, safe, low-cost, and effective therapy as an alternative to exogenous IFN-ß for MS.

Left atrial enlargement and non-paroxysmal atrial fibrillation as risk factors for left atrial thrombus/spontaneous Echo contrast in patients with atrial fibrillation and low CHA2DS2-VASc score.

OBJECTIVE: To determine the risk factors for thromboembolism in lower risk patients with non-valvular atrial fibrillation (AF) and low CHA2DS2-VASc scores, which remain undefined. METHODS: We retrospectively analyzed the baseline clinical characteristics, routine laboratory parameters, and echocardiographic measurements of 705 patients (71.1% male; mean age: 52.10 ± 9.64 years) with low CHA2DS2-VASc score (0 or 1; 1 point for female sex) out of 1346 consecutive patients with non-valvular AF who underwent transesophageal echocardiography (TEE) at Guangdong Cardiovascular Institute between January 2013 and December 2015. RESULTS: Patients with left atrial thrombus (LAT) or spontaneous echo contrast (SEC) on TEE (24/705, 4%) showed a higher incidence rate of vascular disease (54.2% vs. 32.9%, P = 0.045) and non-paroxysmal AF (79.2% vs. 29.4%, P < 0.001), larger left atrial diameter (43.08 ± 4.59 vs. 36.02 ± 5.53 mm, P < 0.001), and lower left ventricular ejection fraction (58.23 ± 8.82% vs. 64.15 ± 7.14%, P < 0.001) than those without. Multivariate logistic regression analysis identified left atrial diameter [odds ratio (OR) = 1.171, 95% confidence interval (CI): 1.084-1.265, P < 0.001] and non-paroxysmal AF (OR = 3.766, 95% CI: 1.282-11.061, P = 0.016) as independent risk factors for LAT/SEC. In ROC curve analysis, a left atrial dimeter cutoff of 37.5 mm yielded 95.0% sensitivity and 62.7% specificity (AUC: 0.847, P < 0.0001, 95% CI: 0.793-0.914). CONCLUSION: In patients with non-valvular AF with low CHA2DS2-VASc score, the presence of LAT or SEC was associated with left atrial enlargement, which had moderate predictive value, and non-paroxysmal AF.

Inability to capture with increasing current strength: Is this near-field or far-field?

We present a case of wide-complex tachycardia in which the clinical electrophysiological diagnosis was considered to be bundle branch re-entry ventricular tachycardia. A series of ventricular entrainment attempts were performed from the left and right ventricular septum to confirm the diagnosis. Entrainment pacing with a general current output (10 mA) was performed from the right ventricular septum with manifest fusion and a post-pacing interval similar to tachycardia cycle length. Thereafter, another entrainment attempt with a greater current output (20 mA) was performed from the same site. Paradoxically, concealed fusion was demonstrated by selective RB capture only, though there was no clear "RB" potential seen. In this case, we attempt to explain and illustrate the mechanism of paradoxical near-field inability to capture with increasing current strength.

High hydrostatic pressure induces atrial electrical remodeling through angiotensin upregulation mediating FAK/Src pathway activation.

Hypertension is an independent risk factor for atrial fibrillation (AF), although its specific mechanisms remain unclear. Previous research has been focused on cyclic stretch, ignoring the role of high hydrostatic pressure. The present study aimed to explore the effect of high hydrostatic pressure stimulation on electrical remodeling in atrial myocytes and its potential signaling pathways. Experiments were performed on left atrial appendages from patients with chronic AF or sinus rhythm, spontaneously hypertensive rats (SHRs) treated with or without valsartan (10 mg/kg/day) and HL-1 cells were exposed to high hydrostatic pressure using a self-developed device. Whole-cell patch-clamp recordings and western blots demonstrated that the amplitudes of ICa,L, Ito, and IKur were reduced in AF patients with corresponding changes in protein expression. Angiotensin protein levels increased and Ang1-7 decreased, while focal adhesion kinase (FAK) and Src kinase were enhanced in atrial tissue from AF patients and SHRs. After rapid atrial pacing, AF inducibility in SHR was significantly higher, accompanied by a decrease in ICa,L, upregulation of Ito and IKur, and a shortened action potential duration. Angiotensin upregulation and FAK/Src activation in SHR were inhibited by angiotensin type 1 receptor inhibitor valsartan, thus, preventing electrical remodeling and reducing AF susceptibility. These results were verified in HL-1 cells treated with high hydrostatic pressure, and demonstrated that electrical remodeling regulated by the FAK-Src pathway could be modulated by valsartan. The present study indicated that high hydrostatic pressure stimulation increases AF susceptibility by activating the renin-angiotensin system and FAK-Src pathway in atrial myocytes.

High hydrostatic pressure induces atrial electrical remodeling through upregulation of inflammatory cytokines.

AIMS: Hypertension is an independent risk factor for atrial fibrillation (AF). However, the direct effect of hydrostatic pressure on atrial electrical remodeling is unclear. The present study investigated whether hydrostatic pressure is responsible for atrial electrical remodeling and addressed a potential role of inflammation in this pathology. MAIN METHODS: Whole-cell patch-clamp recordings and biochemical assays were used to study the regulation and expression of ion channels in left atrial appendages in patients with AF, spontaneously hypertensive rats (SHRs), and atrium-derived cells (HL-1 cells) exposed to standard (0 mmHg) and elevated (20, 40 mmHg) hydrostatic pressure. KEY FINDINGS: Both TNF-α and MIF were highly expressed in patients with AF and SHRs. AF inducibility in SHRs was higher after atrial burst pacing, accompanied by a decrease in the L-type calcium current (ICa,L), an increase in the transient outward K+ current (Ito) and ultra-rapid delayed rectifier K+ current (IKur), and a shortened action potential duration (APD), which could be inhibited by atorvastatin. Furthermore, exposure to elevated pressure was associated with electrical remodeling of the HL-1 cells. The peak current density of ICa,L was reduced, while Ito and IKur were increased. Moreover, the expression levels of Kv4.3, Kv1.5, TNF-α, and MIF were upregulated, while the expression of Cav1.2 was downregulated in HL-1 cells after treatment with high hydrostatic pressure (40 mmHg). Atorvastatin alleviated the electrical remodeling and increased inflammatory markers in HL-1 cells induced by high hydrostatic pressure. SIGNIFICANCE: Elevated hydrostatic pressure led to atrial electrical remodeling and increased AF susceptibility by upregulating inflammation.