Identification of Human Ventricular Tachycardia Demarcated by Fixed Lines of Conduction Block in a 3-Dimensional Hyperboloid Circuit.

BACKGROUND: The circuit boundaries for reentrant ventricular tachycardia (VT) have been historically conceptualized within a 2-dimensional (2D) construct, with their fixed or functional nature unresolved. This study aimed to examine the correlation between localized lines of conduction block (LOB) evident during baseline rhythm with lateral isthmus boundaries that 3-dimensionally constrain the VT isthmus as a hyperboloid structure. METHODS: A total of 175 VT activation maps were correlated with isochronal late activation maps during baseline rhythm in 106 patients who underwent catheter ablation for scar-related VT from 3 centers (42% nonischemic cardiomyopathy). An overt LOB was defined by a deceleration zone with split potentials (≥20 ms isoelectric segment) during baseline rhythm. A novel application of pacing within deceleration zone (≥600 ms) was implemented to unmask a concealed LOB not evident during baseline rhythm. LOB identified during baseline rhythm or pacing were correlated with isthmus boundaries during VT. RESULTS: Among 202 deceleration zones analyzed during baseline rhythm, an overt LOB was evident in 47%. When differential pacing was performed in 38 deceleration zones without overt LOB, an underlying concealed LOB was exposed in 84%. In 152 VT activation maps (2D=53, 3-dimensional [3D]=99), 69% of lateral boundaries colocalized with an LOB in 2D activation patterns, and the depth boundary during 3D VT colocalized with an LOB in 79%. In VT circuits with isthmus regions that colocalized with a U-shaped LOB (n=28), the boundary invariably served as both lateral boundaries in 2D and 3D. Overall, 74% of isthmus boundaries were identifiable as fixed LOB during baseline rhythm or differential pacing. CONCLUSIONS: The majority of VT circuit boundaries can be identified as fixed LOB from intrinsic or paced activation during sinus rhythm. Analysis of activation while pacing within the scar substrate is a novel technique that may unmask concealed LOB, previously interpreted to be functional in nature. An LOB from the perspective of a myocardial surface is frequently associated with intramural conduction, supporting the existence of a 3D hyperboloid VT circuit structure. Catheter ablation may be simplified to targeting both sides around an identified LOB during sinus rhythm.

Deubiquitinating enzyme OTUD4 stabilizes RBM47 to induce ATF3 transcription: a novel mechanism underlying the restrained malignant properties of ccRCC cells.

Dysregulation of deubiquitination contributes to various diseases, including cancer, and aberrant expression of deubiquitinating enzymes is involved in carcinoma progression. As a member of the ovarian tumor (OTU) deubiquitinases, OTUD4 is considered a tumor suppressor in many kinds of malignancies. The biological characteristics and mechanisms of OTUD4 in clear cell renal cell carcinoma (ccRCC) remain unclear. The downregulation of OTUD4 in ccRCC was confirmed based on the TCGA database and a validation cohort of 30-paired ccRCC and para-carcinoma samples. Moreover, OTUD4 expression was detected by immunohistochemistry in 50 cases of ccRCC tissues, and patients with lower levels of OTUD4 showed larger tumor size (p = 0.015). TCGA data revealed that patients with high expression of OTUD4 had a longer overall survival rate. In vitro and in vivo studies revealed that downregulation of OTUD4 was essential for tumor cell growth and metastasis in ccRCC, and OTUD4 overexpression inhibited these malignant phenotypes. We further found that OTUD4 sensitized ccRCC cells to Erastin-induced ferroptosis, and ferrostain-1 inhibited OTUD4-induced ferroptotic cell death. Mechanistic studies indicated that OTUD4 functioned as an anti-proliferative and anti-metastasic factor through the regulation of RNA-binding protein 47 (RBM47)-mediated activating transcription factor 3 (ATF3). OTUD4 directly interacted with RBM47 and promoted its stability via deubiquitination events. RBM47 was critical in ccRCC progression by regulating ATF3 mRNA stability, thereby promoting ATF3-mediated ferroptosis. RBM47 interference abolished the suppressive role of OTUD4 overexpression in ccRCC. Our findings provide mechanistic insight into OTUD4 of ccRCC progression and indicate a novel critical pathway OTUD4/RBM47/ATF3 may serve as a potential therapeutic pathway for ccRCC.

Metformin use correlated with lower risk of cardiometabolic diseases and related mortality among US cancer survivors: evidence from a nationally representative cohort study.

BACKGROUND: In the USA, the prolonged effective survival of cancer population has brought significant attention to the rising risk of cardiometabolic morbidity and mortality in this population. This heightened risk underscores the urgent need for research into effective pharmacological interventions for cancer survivors. Notably, metformin, a well-known metabolic regulator with pleiotropic effects, has shown protective effects against cardiometabolic disorders in diabetic individuals. Despite these promising indications, evidence supporting its efficacy in improving cardiometabolic outcomes in cancer survivors remains scarce. METHODS: A prospective cohort was established using a nationally representative sample of cancer survivors enrolled in the US National Health and Nutrition Examination Survey (NHANES), spanning 2003 to 2018. Outcomes were derived from patient interviews, physical examinations, and public-access linked mortality archives up to 2019. The Oxidative Balance Score was utilized to assess participants' levels of oxidative stress. To evaluate the correlations between metformin use and the risk of cardiometabolic diseases and related mortality, survival analysis of cardiometabolic mortality was performed by Cox proportional hazards model, and cross-sectional analysis of cardiometabolic diseases outcomes was performed using logistic regression models. Interaction analyses were conducted to explore the specific pharmacological mechanism of metformin. RESULTS: Among 3995 cancer survivors (weighted population, 21,671,061, weighted mean [SE] age, 62.62 [0.33] years; 2119 [53.04%] females; 2727 [68.26%] Non-Hispanic White individuals), 448 reported metformin usage. During the follow-up period of up to 17 years (median, 6.42 years), there were 1233 recorded deaths, including 481 deaths from cardiometabolic causes. Multivariable models indicated that metformin use was associated with a lower risk of all-cause (hazard ratio [HR], 0.62; 95% confidence interval [CI], 0.47-0.81) and cardiometabolic (HR, 0.65; 95% CI, 0.44-0.97) mortality compared with metformin nonusers. Metformin use was also correlated with a lower risk of total cardiovascular disease (odds ratio [OR], 0.41; 95% CI, 0.28-0.59), stroke (OR, 0.44; 95% CI, 0.26-0.74), hypertension (OR, 0.27; 95% CI, 0.14-0.52), and coronary heart disease (OR, 0.41; 95% CI, 0.21-0.78). The observed inverse associations were consistent across subgroup analyses in four specific cancer populations identified as cardiometabolic high-risk groups. Interaction analyses suggested that metformin use as compared to non-use may counter-balance oxidative stress. CONCLUSIONS: In this cohort study involving a nationally representative population of US cancer survivors, metformin use was significantly correlated with a lower risk of cardiometabolic diseases, all-cause mortality, and cardiometabolic mortality.

Initial clinical experience of atrial fibrillation ablation guided by a cryoballoon-compatible, magnetic-based circular catheter.

INTRODUCTION: The circular catheter compatible with current cryoballoon system for atrial fibrillation (AF) ablation is exclusively sensed by impedance-based electro-anatomical mapping (EAM) system, limiting the accuracy of maps. We aim to investigate the feasibility and safety of a magnetic-based circular mapping catheter for AF ablation with cryoballoon. METHODS: Nineteen consecutive patients who underwent pulmonary vein isolation (PVI) with cryoballoon for paroxysmal or persistent AF were included. EAMs of left atrium (LA) created by the LASSOSTAR™NAV catheter (Lassostar map) before and after PVI were compared to that generated by a high-density mapping catheter (Pentaray map) from different aspects including structural similarity, PV angle, LA posterior wall (LAPW) and low voltage areas (LVAs), and the amplitude of far field electrograms (FFEs) recorded by catheters. RESULTS: All patients had successful PVI without major complications. With similar mapping time and density, the LA volume calculated from the Pentaray map and Lassostar map were comparable. There were no significant differences in PV angle of all PVs and PW area (16.8 ± 3.2 vs. 17.1 ± 2.8, p = .516) between Pentaray map and Lassostar map. High structural similarity score was observed between two maps (0.783 in RAO/LAO view and 0.791 in PA view). Lassostar map detected lesser but not statistically significant extension of LVA (13.9% vs. 18.3%, p = .07). Amplitude of FFE was larger at the right superior PV on Lassostar map (0.21 ± 0.16 vs. 0.14 ± 0.11 mV, p = .041) compared to that on the Pentaray map. CONCLUSION: In our initial experience, PVI with cryoballoon and magnetic-based circular LASSOSTAR™NAV catheter was safe and effective based on the accurate LA geometry it created.

Reconsideration of the definition of blanking period and significance of early recurrences after catheter ablation of atrial fibrillation.

PURPOSE OF REVIEW: Early recurrence of atrial tachyarrhythmia (ERAT) during blanking period (BP) is not uncommon after catheter ablation of AF. Current guidelines and consensus statements recommend conservative treatment of ERAT. This review summarized recent studies, underlying mechanism and clinical managements of ERAT, and proposed a reconsideration of the definition and clinical significance of BP. RECENT FINDINGS: Recent studies have shown that the entity of ERAT in the very early phase of BP (i.e., first 4 weeks of the 3-month period) is different from those ERATs occurring late which is strongly associated with the late recurrence of atrial tachyarrhythmia. The optimal BP duration suggested by clinical observation ranges from 21 to 58 days. Using antiarrhythmic drugs and early electrical cardioversion are the effective management for ERAT, whereas re-ablation is a reasonable strategy although remains controversial. SUMMARY: The definition of BP with a shorter duration, that is, 1 month instead of 3 months post AF ablation, is supported by the observations of latest clinical studies. Recurrent atrial tachyarrhythmia beyond the 1-month time frame is associated with higher risk of late recurrence and may warrant repeat ablation. A revisit to the guideline recommendation on management of ERAT is needed to change clinical practice.

Use of three-dimensional electroanatomic mapping for epicardial access: needle tracking, electrographic characteristics, and clinical application.

AIMS: Pericardiocentesis is usually completed under fluoroscopy. The electroanatomic mapping (EAM) system allows visualizing puncture needle tip (NT) while displaying the electrogram recorded from NT, making it possible to obtain epicardial access (EA) independent of fluoroscopy. This study was designed to establish and validate a technique by which EA is obtained under guidance of three-dimensional (3D) EAM combined with NT electrogram. METHODS AND RESULTS: 3D shell of the heart was generated, and the NT was made trackable in the EAM system. Unipolar NT electrogram was continuously monitored. Penetration into pericardial sac was determined by an increase in NT potential amplitude and an injury current. A long guidewire of which the tip was also visible in the EAM system was advanced to confirm EA. Epicardial access was successfully obtained without complication in 13 pigs and 22 patients. In the animals, NT potential amplitude was 3.2 ± 1.0 mV when it was located in mediastinum, 5.2 ± 1.6 mV when in contact with fibrous pericardium, and 9.8 ± 2.8 mV after penetrating into pericardial sac (all P ≤ 0.001). In human subjects, it measured 1.54 ± 0.40 mV, 3.61 ± 1.08 mV, and 7.15 ± 2.88 mV, respectively (all P < 0.001). Fluoroscopy time decreased in every 4-5 cases (64 ± 15, 23 ± 17, and 0 s for animals 1-4, 5-8, 9-13, respectively, P = 0.01; 44 ± 23, 31 ± 18, 4±7 s for patients 1-7, 8-14, 15-22, respectively, P < 0.001). In five pigs and seven patients, EA was obtained without X-ray exposure. CONCLUSION: By tracking NT in the 3D EAM system and continuously monitoring the NT electrogram, it is feasible and safe to obtain EA with minimum or no fluoroscopic guidance.

Incidence of cryoballoon expansion dislodgement during pulmonary vein isolation-An underappreciated frequent cause of incomplete isolation.

BACKGROUND: Cryoballoon ablation for atrial fibrillation (AF) requires adequate contact between the pulmonary vein (PV) antrum and cryoballoon. The surge of intraballoon pressure during the initial phase of ablation may change the balloon's shape and compliance, resulting in balloon dislodgement and loss of PV occlusion. Without continuous monitoring, this phenomenon is often undetected but can be associated with incomplete PV isolation (PVI). METHODS: Primary cryoablation of AF was performed in 15 patients. PV occlusion status pre- and post-freezing were analyzed with intracardiac echocardiography (ICE) and dielectric imaging-based occlusion tool (DIOT) to calculate the incidence of expansion dislodgement of cryoballoon. RESULTS: A total of 105 cryoablation applications were performed on 57 veins, including three common ostiums of left pulmonary veins. In the evaluation of PV occlusion, both modalities reported consistent results in 86.7% of the assessments. Despite complete PV occlusion before ablation, peri-balloon leak after initiation of freezing was detected by ICE in 5/22 (22.7%) applications and by DIOT in 8/25 (32%) applications. CONCLUSION: Incidence of expansion dislodgement of the cryoballoon was detected in one-fourth to one-third of cryoablation applications depending on the imaging modality used, which was clinically frequent and significant.

Endoscopic submucosal resection (ESD) and endoscopic full-thickness resection (EFTR) via balloon-assisted enteroscopy (BAE) in small bowel subepithelial lesions: experience in treating fifteen cases.

AIM: The study objective was to evaluate the primary feasibility of endoscopic submucosal resection (ESD) and endoscopic full-thickness resection (EFTR) via balloon-assisted enteroscopy (BAE) to treat small bowel subepithelial lesions (SELs). METHOD: A retrospective case series study was performed. The first fifteen consecutive patients who underwent ESD (n = 10) and EFTR (n = 5) via BAE to remove small bowel SELs from November 2016 to December 2023 were included. The main outcome measures were the technique success rate, operative time and complication rate. RESULTS: This research focused on 15 cases of jejunoileal SELs, four cases of lipomyoma, three cases of ectopic pancreas, two cases of NETs, three cases of benign fibrous tumours and three cases of angioma. The overall technique success rate was 86.7%, with 100% (10/10) and 60% (3/5) for BAE-ESD and BAE-EFTR, respectively, in removing small bowel SELs. Two cases of EFTR failed, as the BAE operation was unsuitable for tumour resection and suture repair of a perforated wound. No serious bleeding or any postoperative complications occurred. The median time of endoscopic resection via BAE for SELs was 44 min (range 22-68 min). CONCLUSION: ESD and EFTR via BAE might be alternative choices for treating small SELs in the small bowel, with the advantages of clear and accurate positioning and minimal invasiveness. However, its superiority over surgery still needs to be further investigated.

Effect of electron beam irradiation on glycosylation reaction and structural characterization of whey isolate protein.

BACKGROUND: Whey protein isolate (WPI) is a high-quality animal protein resource. The modification of WPI through physical, chemical and biological methods can substantially improve the functional properties of proteins. This study investigated the effect of electron beam irradiation (EBI) on the modification of WPI-xylose glycosylation. RESULTS: The degree of grafting and browning revealed that EBI promoted WPI glycosylation. The maximum emission wavelength of intrinsic fluorescence was red-shifted and the fluorescence intensity was reduced, suggesting that irradiation induced the unfolding of the WPI structure, thereby promoting glycosylation. Fourier-transformed infrared spectroscopy revealed that the covalent binding of the conjugates occurred on the introduction of the hydrophilic groups, resulting in decreased surface hydrophobicity. When compared with conventional wet-heat glycosylation, irradiation-assisted glycosylation improved the emulsifying activity of WPI from 179.76 ± 0.83 to 277.83 ± 1.44 m2 g-1, and the emulsifying and rheological properties improved. CONCLUSION: These results confirmed that EBI can increase the degree of WPI glycosylation and improve the functional properties of proteins, thereby laying a theoretical foundation for the further application of WPI. © 2024 Society of Chemical Industry.

Gender-Specific Trajectories of Non-Suicidal Self-Injury among Adolescents: Predictive Roles of Distal and Proximal Risk Factors.

Non-suicidal self-injury (NSSI) is considered a strong risk factor for suicide. Although NSSI is prevalent among adolescents and varies by gender, few studies have examined the gender-specific trajectory of NSSI and its predictors. This study examined the trajectory of NSSI among Chinese adolescent boys and girls separately, and the roles of distal (i.e., childhood maltreatment and its specific subtypes) and proximal risk factors (i.e., emotional dysregulation, peer victimization) on their trajectories. A total of 3290 Chinese adolescents (Mage = 13.08; SD = 0.84; 57.6% boys) participated in assessments at three time points. Latent class growth models identified three trajectories for boys: Low stable (92.5%), moderate increasing (5.0%) and high decreasing (2.5%). Four trajectories were identified for girls: Low stable (87.9%), moderate increasing (7.6%), high decreasing (3.0%) and high stable (1.5%). Multinomial logistic regression analyses revealed that both emotional dysregulation and emotional abuse predicted the trajectories of moderate increasing, high decreasing and high stable for girls, as well as predicted moderate increasing and high decreasing trajectories for boys. Peer victimization served as a significant risk factor predicting the moderate increasing and high decreasing trajectories only for girls, while overall childhood maltreatment was a remarkable predictor for the moderate increasing and high decreasing trajectories of boys. The findings highlighted the importance of gender differences in understanding the progression of NSSI and the key predictors, informing effective strategies for prevention and intervention.

[Network Meta-analysis of Chinese patent medicine in treatment of heart failure with preserved ejection fraction].

This study systematically evaluated the efficacy and safety of different Chinese patent medicines combined with conventional western medicine in the treatment of heart failure with preserved ejection fraction(HFpEF) and ranked for the drug selection. Randomized controlled trial(RCT) on Chinese patent medicines in treatment of HFpEF were obtained from the CNKI, Wanfang, VIP, SinoMed, PubMed, Cochrane Library, EMbase, Web of Science, and other databases from the inception to October 9, 2022. The included RCT was quantitatively analyzed using gemtc and rjags packages of R software for the network Meta-analysis. 74 RCTs were included, with a total of 7 192 patients enrolled, involving 11 different Chinese patent medicines(Shenfu Injection, Shenmai Injection, Qili Qiangxin Capsules, Shexiang Baoxin Pills, Xuezhikang Capsules, Salvia Miltiorrhiza Polyphenols Injection, Tanshinone Ⅱ_A Sulfonate Injection, Xinmailong Injection, Yangxinshi Tablets, Qishen Yiqi Dripping Pills, and Yixinshu Capsules). The results of network Meta-analysis are shown as followed.(1)In terms of improving clinical effective rate, for injection preparations, Xinmailong Injection + conventional western medicine was recommended. while for oral preparations, Shexiang Baoxin Pills + conventional western medicine, Qishen Yiqi Dripping Pills + conventional western medicine, and Qili Qiangxin Capsules + conventional western medicine were preferred.(2)In terms of improving the mitral ratio of peak early to late diastolic filling velocity(E/A), for injection preparations, Shenmai Injection + Salvia Miltiorrhiza Polyphenols Injection + conventional western medicine, Shenmai Injection + conventional western medicine, Shenfu Injection + conventional western medicine were preferred. While for oral preparations, Yixinshu Capsules + conventional western medicine was preferred.(3)In terms of reducing the ratio of early diastolic mitral inflow to early diastolic mitral annular velocity(E/e'), Shenfu Injection + conventional western medicine could be used as injection preparation, and Qili Qiangxin Capsules + conventional western medicine, Qishen Yiqi Dripping Pills + conventional western medicine for oral preparations.(4)In terms of improving 6-minute walking trail(6MWT), the injection preparations such as Shenmai Injection + conventional western medicine, Xinmailong Injection + conventional western medicine were suitable, while oral preparations like Qishen Yiqi Dripping Pills + conventional western medicine, Qili Qiangxin Capsules + conventional western medicine were recommended.(5)In terms of reducing N-terminal pro B-type natriuretic peptide(NT-proBNP), Qili Qiangxin Capsules + conventional western medicine were preferred.(6)In terms of reducing B-type natriuretic peptide(BNP), Xinmailong Injection + conventional western medicine could be used for injection preparation and Qili Qiangxin Capsules + conventional western medicine can be used for oral preparation. In terms of adverse drug reactions, there was no significant difference between Chinese patent medicine combined with conventional western conventional and traditional western medicine alone. The results showe that Chinese patent medicine combined with conventional western medicine in treating HFpEF is superior to conventional western medicine alone in reducing clinical symptoms, improving cardiac function, and improving exercise tolerance, which also has good drug safety. However, the existing evidence is still limited by the quality and quantity of included studies, so the above conclusion requires further validation through more prospective RCT.

Prospective randomized comparison between upgraded '2C3L' vs. PVI approach for catheter ablation of persistent atrial fibrillation: PROMPT-AF trial design.

BACKGROUND: In randomized studies, the strategy of pulmonary vein antral isolation (PVI) plus linear ablation has failed to increase success rates for persistent atrial fibrillation (PeAF) ablation when compared with PVI alone. Peri-mitral reentry related atrial tachycardia due to incomplete linear block is an important cause of clinical failures of a first ablation procedure. Ethanol infusion (EI) into the vein of Marshall (EI-VOM) has been demonstrated to facilitate a durable mitral isthmus linear lesion. OBJECTIVE: This trial is designed to compare arrhythmia-free survival between PVI and an ablation strategy termed upgraded '2C3L' for the ablation of PeAF. STUDY DESIGN: The PROMPT-AF study (clinicaltrials.gov 04497376) is a prospective, multicenter, open-label, randomized trial using a 1:1 parallel-control approach. Patients (n = 498) undergoing their first catheter ablation of PeAF will be randomized to either the upgraded '2C3L' arm or PVI arm in a 1:1 fashion. The upgraded '2C3L' technique is a fixed ablation approach consisting of EI-VOM, bilateral circumferential PVI, and 3 linear ablation lesion sets across the mitral isthmus, left atrial roof, and cavotricuspid isthmus. The follow-up duration is 12 months. The primary end point is freedom from atrial arrhythmias of >30 seconds, without antiarrhythmic drugs, in 12 months after the index ablation procedure (excluding a blanking period of 3 months). CONCLUSIONS: The PROMPT-AF study will evaluate the efficacy of the fixed '2C3L' approach in conjunction with EI-VOM, compared with PVI alone, in patients with PeAF undergoing de novo ablation.

Risk Factors for Left Ventricular Thrombus Formation in Patients with Dilated Cardiomyopathy.

BACKGROUND: Left ventricular thrombus (LVT) is a common complication of dilated cardiomyopathy (DCM), causing morbidity and mortality. METHODS: This study retrospectively analyzed patients with DCM from January 2002 to August 2020 in Beijing Anzhen Hospital. Clinical characteristics were compared between the LVT group and the age and sex 1:4 matched with the LVT absent group. The receiver operator characteristic (ROC) curve was plotted to evaluate the diagnostic value of D-dimer predicting LVT occurrence in DCM. RESULTS: A total of 3,134 patients were screened, and LVT was detected in 72 (2.3%) patients on echocardiography. The patients with LVT had higher D-dimer, fibrinogen, and lower systolic blood pressure than those without LVT. The ejection fraction (EF) was lower and left ventricular end-systolic diameter was larger in the LVT group. Severe mitral regurgitation (MR) was more common in the LVT absent groups. The prevalence of atrial fibrillation was lower in the LVT group. The ROC curve analysis yielded an optimal cut-off value of 444 ng/mL DDU (D-dimer units) for D-dimer to predict the presence of LVT. Multivariable binary logistic regression analysis revealed that EF (OR = 0.90, 95% CI = 0.86-0.95), severe MR (OR = 0.19, 95% CI = 0.08-0.48), and D-dimer level (OR = 15.4, 95% CI = 7.58-31.4) were independently associated with LVT formation. CONCLUSION: This study suggested that elevated D-dimer levels (>444 ng/mL DDU) and reduced EF were independently associated with increased risk of LVT formation. Severe MR could decrease the incidence of LVT.

Successful ablation of a right epicardial accessory pathway via the right ventricular diverticulum in a patient with Wolff-Parkinson-White syndrome.

INTRODUCTION: We describe one rare case of successful ablation of a right epicardial accessory pathway (AP) via the right ventricular diverticulum in a patient with Wolff-Parkinson-White syndrome. METHODS: A 42-year-old woman was referred to the hospital for a catheter ablation of Wolf-Parkinson-White syndrome. The earliest activation was shown to be present in the region of the tricuspid annulus. However, ablation had no effect on the AP. RESULTS: We decided to do a selected angiography, in which a big diverticulum near the right tricuspid annulus was shown to be present. Ablation in this region successfully repressed the AP without any recurrences within a follow-up period of 12 months. CONCLUSION: The ventricular diverticulum-mediated AP is a novel variant of pre-excitation. It can serve as an anatomical substrate of supraventricular tachycardia, and can be ablated endocardially using an irrigation tip catheter within the diverticulum.

Risk and benefit of extrapulmonary vein ablation in atrial fibrillation.

PURPOSE OF REVIEW: This review aims to summarize the recent development, benefit, and safety of extrapulmonary vein ablation for atrial fibrillation. RECENT FINDING: Studies have shown that extrapulmonary vein ablation can help maintain normal sinus rhythm for patients with persistent atrial fibrillation. As prior strategies targeting anatomical lines and triggers are well utilized, novel techniques for substrate mapping have been rapidly developing. These strategies are well tolerated and could be chosen based on patients' conditions and physicians' experience. SUMMARY: Extrapulmonary vein ablation could be safely and effectively performed for patients with atrial fibrillation. It provides further consolidation of normal sinus rhythm.

Visualization and mapping of the right phrenic nerve by intracardiac echocardiography during atrial fibrillation ablation.

OBJECTIVE: This study aimed to evaluate the feasibility of real-time visualization and mapping of the right phrenic nerve (RPN) by using intracardiac echocardiography (ICE) during atrial fibrillation (AF) ablation. BACKGROUND: RPN injury is a complication associated with the ablation of AF. Multiple approaches are currently being used to prevent and detect RPN injuries. However, none of these approaches can directly visualize the RPN in real-time during the ablation procedure. METHODS AND RESULTS: The RPN was detected using ICE. The RPN and its adjacent structures were analysed. The relationship between the RPN's distance from the superior vena cava (SVC) and its pacing capture threshold was quantified. The safety of SVC isolation guided by the ICE-visualized RPN was evaluated. Thirty-eight people were enrolled in this study. The RPN was visualized by ICE in 92% of patients. It ran through the space between the SVC and the mediastinal pleura and had a 'straw'-like appearance upon ICE imaging. The course of the RPN was close to the SVC (minimum 1.0 ± 0.4 mm) and the right superior pulmonary vein (minimum 14.1 ± 7.3 mm). There was a positive linear correlation between the RPN's capture threshold and its distance from the SVC (Spearman's correlation coefficient = 0.728, < 0.001). SVC isolation was guided by the RPN; none of the patients developed an RPN injury. CONCLUSIONS: RPN can be visualized by ICE in most patients, thus providing a novel approach for the real-time detection of RPN during AF ablation.

Efficiency and safety of high-power ablation guided by Lesion size index: An ex vivo porcine heart study.

BACKGROUND: Although Lesion size index (LSI) has been reported to highly predict radiofrequency lesion size in vitro, its accuracy in lesion size and steam pop estimation has not been well investigated for every possible scenario. METHODS: Initially, radiofrequency ablations were performed on porcine myocardial slabs at various power, CF, and time settings with blinded LSI. Subsequently, radiofrequency power at 20, 30, 40, 50, and 60 W was applied at CF values of 5, 10, 20, and 30 g to reach target LSIs of 4, 5, 6, and 7. Lesion size and steam pops were recorded for each ablation. RESULTS: Lesion size was positively correlated with LSI regardless of power settings (p < 0.001). The linear correlation coefficients of lesion size and LSI decreased at higher power settings. At high power combined with high CF settings (50 W/20 g), lesion depth and LSI showed an irrelevant correlation (p = 0.7855). High-power ablation shortened ablation time and increased the effect of resistive heating. LSI could predict the risk of steam pops at high-power settings with the optimal threshold of 5.65 (sensitivity, 94.1%; specificity, 46.1%). The ablation depth of the heavy heart was shallower than that of the light heart under similar ablation settings. CONCLUSIONS: LSI could predict radiofrequency lesion size and steam pops at high power settings in vitro, while synchronous high power and high CF should be avoided. Lighter hearts require relatively lower ablation settings to create appropriate ablation depth.

Sertoli cell survival and barrier function are regulated by miR-181c/d-Pafah1b1 axis during mammalian spermatogenesis.

Sertoli cells contribute to the formation of the blood-testis barrier (BTB), which is necessary for normal spermatogenesis. Recently, microRNAs (miRNAs) have emerged as posttranscriptional regulatory elements in BTB function during spermatogenesis. Our previous study has shown that miR-181c or miR-181d (miR-181c/d) is highly expressed in testes from boars at 60 days old compared with at 180 days old. Herein, we found that overexpression of miR-181c/d via miR-181c/d mimics in murine Sertoli cells (SCs) or through injecting miR-181c/d-overexpressing lentivirus in murine testes perturbs BTB function by altering BTB-associated protein distribution at the Sertoli cell-cell interface and F-actin organization, but this in vivo perturbation disappears approximately 6 weeks after the final treatment. We also found that miR-181c/d represses Sertoli cell proliferation and promotes its apoptosis. Moreover, miR-181c/d regulates Sertoli cell survival and barrier function by targeting platelet-activating factor acetylhydrolase 1b regulatory subunit 1 (Pafah1b1) gene. Furthermore, miR-181c/d suppresses PAFAH1B1 expression, reduces the complex of PAFAH1B1 with IQ motif-containing GTPase activating protein 1, and inhibits CDC42/PAK1/LIMK1/Cofilin pathway which is required for F-actin stabilization. In total, our results reveal the regulatory axis of miR-181c/d-Pafah1b1 in cell survival and barrier function of Sertoli cells and provide additional insights into miRNA functions in mammalian spermatogenesis.

SPAG6 c.900 T>C affects boar semen quality and blood-testis barrier function by creating a new splice acceptor site.

Sperm associated antigen 6 (SPAG6) acts as a scaffolding protein in the center of the flagellar axoneme and has an impact on the maturation of the motility of mammalian sperm flagella and the maintenance of sperm structure. In our previous research, SPAG6 c.900 T>C in exon 7 and exon 7 skipped transcript was identified by analyzing RNA-seq data of testicular tissues from 60 day (sexually immature) and 180 day (sexually mature) Large White boars. Herein, we found porcine SPAG6 c.900 T>C to be associated with semen quality traits in Duroc, Large White and Landrace pigs. SPAG6 c.900 C can generate a new splice acceptor site, inhibit the occurrence of SPAG6 exon 7 skipping to a certain extent, thereby promote the growth of Sertoli cells and maintain the normal blood-testis barrier function. This study provides new insights into the molecular regulation of spermatogenesis and a new genetic marker for the improvement of semen quality in pigs.

Gallbladder disease is associated with the risk of cardiovascular disease among Uyghurs in Xinjiang: a prospective cohort study.

BACKGROUND: Gallbladder disease (GBD) can increase the risk of cardiovascular disease (CVD). However, GBD has rarely been reported in the less developed, rural areas of Xinjiang. This study aimed to determine the prevalence of GBD and incidence of CVD in a prospective cohort study in rural Xinjiang. Moreover, the study aimed to explore the association between GBD and CVD within this cohort. METHODS: The study cohort included 11,444 Uyghur adults in Xinjiang, 3rd division, from the 51st Mission. Study groups were classified according to whether GBD was present or absent at baseline. The occurrence of CVD was the end event. Demographic, anthropometric, and biochemical data were recorded, and the incidence of CVD in the GBD and non-GBD groups analysed. Cox proportional hazards regression models were used to assess the association between GBD and CVD and factors associated with their incidence. Several subgroup analyses were performed to assess CVD incidence in different subgroups. The interaction between GBD and cardiometabolic risk factors, and subsequent risk of developing CVD, was evaluated. RESULTS: Prevalence of GBD in the study cohort was 10.29%. After a median follow-up of 4.92 years, the cumulative incidence of CVD in the study cohort was 10.49%, 8.43% in males and 12.65% in females. CVD incidence was higher in the GBD group (34.04% vs. 7.78%, HR = 4.96, 95% CI: 4.40-5.59). After multivariate adjustment, the risk of CVD remained higher in the GBD group (HR = 2.89, 95% CI: 2.54-3.29). Subgroup analyses showed male sex, smoking, alcohol consumption, lack of exercise, and abnormal renal function were all associated with increased risk of CVD. Moreover, the risk of CVD was markedly higher in GBD combined with cardiometabolic risk factors (hypertension, T2DM, dyslipidaemia, overweight, and abdominal obesity), than in cardiometabolic risk factors alone and this was higher in the GBD group than in the non-GBD group regardless of whether cardiometabolic risk factors were combined. CONCLUSION: GBD is an important independent risk factor for CVD development. Awareness of these associations will raise concerns among clinicians about the risk of cardiovascular disease in patients with GBD.