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In the last three decades, ablation of atrial fibrillation (AF) has become an evidence-based safe and efficacious treatment for managing the most common cardiac arrhythmia. In 2007, the first joint expert consensus document was issued, guiding healthcare professionals involved in catheter or surgical AF ablation. Mounting research evidence and technological advances have resulted in a rapidly changing landscape in the field of catheter and surgical AF ablation, thus stressing the need for regularly updated versions of this partnership which were issued in 2012 and 2017. Seven years after the last consensus, an updated document was considered necessary to define a contemporary framework for selection and management of patients considered for or undergoing catheter or surgical AF ablation. This consensus is a joint effort from collaborating cardiac electrophysiology societies, namely the European Heart Rhythm Association, the Heart Rhythm Society (HRS), the Asia Pacific HRS, and the Latin American HRS. [ABSTRACT FROM AUTHOR]

Background: The P-wave terminal force in lead V1 (PTFV1) is a marker of cardiomyopathy and risk of atrial fibrillation (AF). Low-voltage area (LVA) in the left atrium (LA), which indicates underlying atrial fibrosis, could predict AF recurrence. This study aimed to investigate the correlation between PTFV1 and LVA in older patients with paroxysmal AF. Methods: From May 1, 2020, to October 31, 2021, a total of 162 patients aged 65–80 years with paroxysmal AF who underwent index ablation procedures were enrolled. PTFV1 was measured in sinus rhythm (SR) using 12-lead electrocardiograms prior to the ablation. Abnormal PTFV1 was defined as a ≥ 4 mVms depression. Additional LVA ablation beyond circumferential pulmonary vein isolation (CPVI) was performed if LVAs were found. Results: Among the 162 patients, 88 had a normal PTFV1 and 74 had an abnormal PTFV1 prior to ablation. There was a significant difference in LVA in patients with and without an abnormal PTFV1 (LVA, 11.0 vs. 5.1 cm2, P < 0.001; LVA burden, 8.9% vs. 4.5%, P < 0.001). PTFV1 and PTAV1 were highest in the upper tertile with extensive LVAs (P < 0.001). Multivariate analysis revealed that abnormal PTFV1 was an independent predictor of LVAs (β = 4.961; 95% CI, 2.135–7.788; P < 0.001). After a median follow-up of 23 months, the AF-free survival rate was similar between the normal PTFV1 group and the abnormal PTFV1 group (13/88 vs. 12/74, hazard ratio [HR], 0.933 [95% CI, 0.425–2.047]; P = 0.861). Conclusions: Abnormal PTFV1 at baseline was independently associated with the extent of LVA in older patients with paroxysmal AF. [ABSTRACT FROM AUTHOR]

In this investigation, four classical chemical oxidizing agents—hydrogen peroxide (H2O2), Fenton reagent, sodium persulfate (Na2S2O8), and potassium permanganate (KMnO4)—were employed to remediate soils contaminated with BTEXs (benzene, toluene, ethylbenzene, and xylene). Simultaneously, ecotoxicity assays were integrated to comprehensively evaluate the consequences of the remediation efforts. The various oxidizing agents demonstrated efficient removal of BTEXs from the soil at appropriate concentrations. Post-remediation ecotoxicity evaluations indicated that H2O2 and KMnO4 treatments had the least phytotoxic effects on soil. On the contrary, high doses of Fenton and Na2S2O8 treatments significantly increased the phytotoxicity of the soil. Each of the four oxidative interventions led to a reduced survival rate among earthworms, with a particularly pronounced effect observed at high concentrations of Na2S2O8. The oxidation of water-soluble substances in the soil by Fenton and Na2S2O8 exerted a significant inhibitory impact on the luminous intensity of luminescent bacteria. Conversely, the remediation with KMnO4 substantially alleviated the aquatic biotoxicity of soil leachate. This deleterious effect was mitigated by the application of low concentrations of H2O2 and Fenton. However, the utilization of KMnO4 resulted in a significant reduction in the diversity of soil microbial communities. [ABSTRACT FROM AUTHOR]

In recent years, action recognition has been an essential branch of video understanding and a hot research direction. Among them, the graph convolutional network (GCN) is widely used in skeleton-based action recognition and has achieved remarkable performance. However, in practical situations, recognizing human action often depends on the movement of a part of the joints. In the existing GCN-based methods, the size of a single frame of the skeleton graph is fixed, and all joints of the human body will participate in the whole operation process, so the critical joints in the moving process cannot be flexibly selected. Therefore, this paper takes the adaptive graph convolutional network (AGCN) as the baseline and uses the graph-pooling method to select the critical joints in the human moving process. We design two new networks: Pooling-AGCN and U-AGCN and use them to form the multi-stream P&U AGCNs for action recognition. Extensive experiments show the complementarity between the two networks and that the method proposed in this paper outperforms the recent work on the three large-scale public datasets (NTU-RGB+D 60, NTU-RGB+D 120, Kinetics-Skeleton). [ABSTRACT FROM AUTHOR]

Fertilization can change the composition of antibiotic resistance genes(ARGs) and their host bacteria in agricultural fields, while complex microbial activities help ARGs into crops and transmit them to humans through agricultural products.Therefore, this study constructed a farmland food chain with soil-lettuce-snail as a typical structure, added genetically engineered Pseudomonas fluorescens containing multidrug-resistant plasmid RP4 to track its spread in the farmland food chain, and used different fertilization methods to explore its influence on the spread and diffusion of ARGs and intl1 in the farmland food chain. It was found that exogenous Pseudomonas can enter plants from soil and pass into snails' intestines, and there is horizontal gene transfer phenomenon of RP4 plasmid in bacteria. At different interfaces of the constructed food chain, the addition of exogenous drug-resistant bacteria had different effects on the total abundance of ARGs and intl1. Fertilization, especially manure, not only promoted the spread of Pseudomonas aeruginosa and the transfer of RP4 plasmid levels, but also significantly increased the total abundance of ARGs and intl1 at all interfaces of the constructed food chain. The main ARGs host bacteria in the constructed food chain include Proteobacteria, Bacteroides, and Firmicutes, while Flavobacterium of Bacteroides is the unique potential host bacteria of RP4 plasmid. In conclusion, this study provides a reference for the risk assessment of ARGs transmitted to the human body through the food chain, and has important practical significance to reduce the antibiotic resistance contamination of agricultural products and ensure the safety of vegetable basket. [ABSTRACT FROM AUTHOR]

Earthworms play an important role in the soil environment. To explore the difference in earthworms influence on various media in different soil-plant systems, the abundance of tetracycline, sulfonamide and quinolone resistance genes and the structure of the bacterial community were analysed from five different media including non-rhizosphere soil, rhizosphere soil, phyllosphere, root endophytes and earthworm intestine by real-time quantitative PCR and high-throughput 16S rRNA sequencing. Studies have shown that earthworms can reduce the absolute abundance of antibiotic resistance genes (ARGs) in non-rhizosphere soil. Root endophytes in the soil-cabbage system and rhizosphere soil in the soil-setaria system had the same findings. Earthworms can change the bacterial community structure, especially that of Proteobacteria and Cyanobacteria in the phyllosphere and root endophytes. Redundancy analysis (RDA) results that bacterial community change was the main factor affecting ARGs. In addition, earthworms increased the proportion of Cyanobacteria in root endophytes, and Cyanobacteria was significantly positively correlated with sul3. This study provides a scientific basis for controlling the migration and diffusion of ARGs and reducing environmental risks in soil-plant systems in the future. [ABSTRACT FROM AUTHOR]

Background: Animal studies demonstrated that deeper lesions could be achieved during radio-frequency catheter ablation (RFCA) by using half saline (HS) compared to normal saline (NS) as irrigation. Objectives: This study sought to compare the efficiency and safety of HS and NS for irrigation during RFCA of idiopathic outflow tract ventricular arrhythmia (OT-VA). Methods: In this multicenter, randomized controlled study, 167 patients undergoing RFCA of OT-VA were randomized 1:1 to receive HS- or NS-irrigated ablation. Acute success was defined as the absence of induced targeted premature ventricular contraction (PVC) at the end of the procedure. The 6-month success was defined as a ≥ 80% reduction of pre-procedural PVC burden. Results: There were no differences of baseline characteristics between the HS and NS group. Patients in HS group had shorter total ablation time (259.5 ± 155.5 S vs. 355.6 ± 230.7 S, P = 0.04) than that in NS group. The acute and 6-month success rates were similar between the HS and NS group (92.8 vs. 91.7%, P = 0.79; 90.9 vs. 92.1%, P = 0.79, respectively). No significant difference was observed in the incidence of steam pops between the HS and NS group (2.4 vs. 1.2%, P = 0.62). Conclusions: The ablation using HS irrigation achieved similar success rate and safety compared to that using NS irrigation but was associated with a shorter total ablation time. Trial registration: Chinese Clinical Trial Registry (ChiCTR2200059205) [ABSTRACT FROM AUTHOR]

Background: This study aims to evaluate the prevalence, clinical characteristics, electrophysiological mechanisms, and long-term outcomes of right atrial tachycardia (AT) in patients who underwent ablation for atrial fibrillation (AF). Methods: From March 2010 to December 2020, 220 consecutive patients undergoing index AF ablation were referred for post-ablation AT recurrence. Thirty-five patients (35/220, 15.9%) with right AT recurrence (25 men; mean age 59.3 ± 10.2 years) were enrolled. These patients were divided into groups with right ATs exclusively (group 1) and right combined with left ATs (group 2). Results: Fifty-three ATs were mapped in all patients, with thirty-nine ATs originating from the right atrium. The detailed distribution of all right ATs was 22 in the cavo-tricuspid isthmus (CTI), 6 in the ostium of superior vein cava (SVC), 4 in the right free wall, 4 in the right anterior atrial septum, 2 in coronary sinus ostium, and 1 in crista terminalis. Group 2 had a significantly higher incidence of typical atrial flutter (AFL) than group 1 (11/12, 90.9% vs. 12/24, 50.0%, P = 0.03). During the mean follow-up of 43.6 ± 25.2 months after the index AT ablation, the recurrence rate of AT/AF was 22.9% (8/35), and it was lower in group 1 than in group 2 (8.3% vs. 54.5%, P = 0.01). Conclusion: Right AT is relatively less common post-AF ablation. The CTI-dependent AFL and the ostium of SVC-derived focal AT constituted the major components of right ATs, suggesting the importance of ablation- and anatomy-related arrhythmogenic effects in the right atrium. [ABSTRACT FROM AUTHOR]

The accurate assessment of cardiac motion is crucial for diagnosing and monitoring cardiovascular diseases. In this context, digital volume correlation (DVC) has emerged as a promising technique for tracking cardiac motion from cardiac computed tomography angiographic (CTA) images. This paper presents a comprehensive performance evaluation of the DVC method, specifically focusing on tracking the motion of the left atrium using cardiac CTA data. The study employed a comparative experimental approach while simultaneously optimizing the existing DVC algorithm. Multiple sets of controlled experiments were designed to conduct quantitative analyses on the parameters “radius” and “step”. The results revealed that the optimized DVC algorithm enhanced tracking accuracy within a reasonable computational time. These findings contributed to the understanding of the efficacy and limitations of the DVC algorithm in analyzing heart deformation. [ABSTRACT FROM AUTHOR]

Massive antibiotic resistance genes (ARG) were detected in the soil modified by manure, which may affect human life safety through the food chain. However, the transmission of ARGs through the soil–plant-animal food chain is still unclear. Therefore, this study used high-throughput quantitative PCR technology to explore the effects of pig manure application on ARGs and bacterial communities in soil, lettuce phyllosphere, and snail excrement. The results showed that a total of 384 ARGs and 48 MEGs were detected in all samples after 75 days of incubation. The diversity of ARGs and MGEs in soil components increased significantly by 87.04% and 40% with the addition of pig manure. The absolute abundance of ARGs in the phyllosphere of lettuce was significantly higher than that of the control group, with a growth rate of 212.5%. Six common ARGs were detected between the three components of the fertilization group, indicating that there was internal transmission of fecal ARGs between the trophic levels of the food chain. Firmicutes and Proteobacteria were identified as the dominant host bacteria in the food chain system, which were more likely to be used as carriers of ARGs to promote the spread of resistance in the food chain. The results were used to assess the potential ecological risks of livestock and poultry manure. It provides theoretical basis and scientific support for the formulation of ARG prevention and control policies. [ABSTRACT FROM AUTHOR]

Renal denervation (RDN) is proposed as a durable and patient compliance independent treatment for hypertension. However, 20–30% non-responder after RDN treatment weakened the therapeutic effect, which may be due to blind ablation. The renal nerve mapping/selective ablation system developed by SyMap Medical Ltd (Suzhou), China, has the function of mapping renal sympathetic/parasympathetic nerve sites and selectively removing renal sympathetic nerves and is expected to meet the urgent unmet clinical need of targeted RDN. The "Sympathetic Mapping/Ablation of Renal Nerves Trial" (SMART) is a prospective, multicenter, randomized, single-blinded, sham procedure-controlled trial, to evaluate the safety and efficacy of targeted renal sympathetic denervation in patients with essential and uncontrolled hypertension. The study is the first clinical registry trial using a targeted RDN for the treatment of uncontrolled hypertension; the dual-endpoint design can answer the question of how many antihypertensive drugs can be reduced in patients after RDN. The trial is registered on clinicaltrials.gov NCT02761811. [ABSTRACT FROM AUTHOR]

Purpose: Idiopathic epicardial ventricular arrhythmias (VAs) are clustered in the areas of the summit and crux. This study was to report a group of idiopathic epicardial VAs remote from the summit and crux areas. Methods: In total, 9 patients (6 males, mean age 32 ± 13 years) were enrolled. The locations were identified by epicardial mapping and ablation. The electrocardiographic and electrophysiological characteristics were compared to those of 9 patients who had VAs ablated at the opposite endocardial site. Results: VAs were identified at the epicardium, with 4 patients had VAs located at the inferior wall, one at the anterior wall, one at the apex and 3 patients had VAs at the lateral wall. A "QS" type at the location-related leads was the only identified surface electrocardiogram indication suggesting epicardial origin (compared to that of the controls, 100% vs 0%, p<0.001). Endocardial and epicardial mapping revealed pre-maturities of −11 ± 4 ms and −25 ± 8 ms, respectively (VS. −28 ± 8 ms revealed by endocardial mapping in control patients, p<0.001 and p=0.389, respectively). All of the study cases demonstrated an "rS" pattern in the endocardial unipolar electrogram. Acute and long-term successful ablation (a median of 11 months of follow-up) was achieved in all patients without complications. Conclusions: A distinct group of idiopathic VAs remote from the summit and crux areas warranting ablation by a subxiphoid approach were identified. Morphological ECG features of a "QS" type among the location-related grouped leads combined with the mapping findings helped in the identification of the epicardial site of origin. [ABSTRACT FROM AUTHOR]

Background: Late recurrence after ablation remains a significant issue in patients with premature ventricular complexes (PVCs) who undergo catheter ablation. In this study, we aimed to test the hypothesis that empirical additional ablation (EAA) would improve the long-term control of PVCs from outflow tracts (OT-PVCs) compared with the approach of limited single point ablation at the assumptive location. Methods: EASE-PVC study (ChiCTR2200055340) is a prospective multi-center, randomized, and controlled trial designed to assess the effectiveness and safety of empirical additional ablation in patients with OT-PVCs. After successful elimination of OT-PVCs, the patients will be randomized into two groups. In patients randomized to the EAA group, additional lesion applications at sites surrounding the successful ablation site will be delivered empirically. For patients randomized to the control group, no additional empiric ablation will be performed around the successful ablation site. The primary endpoint will be freedom from PVC recurrence at 3 months following ablation, without antiarrhythmic drug therapy. Conclusions: The EASE-PVC study is designed to compare the effectiveness and safety of two different strategies for ablation in patients with OT-PVCs, namely empirical additional ablation strategy versus conventional single point ablation strategy. This prospective, multi-center, and randomized controlled trial, with comparative data evaluating procedural and long-term follow-up results, aims to elucidate the superiority of empirical additional ablation for the long-term control of OT-PVCs compared with the traditional single point ablation strategy. Clinical trial registration: Chinese Clinical Trials Registry Identifier: ChiCTR2200055340. [ABSTRACT FROM AUTHOR]

The antibiotic resistance gene (ARG) content of composted pig manure remains high, but little is known about the impacts of its use in agriculture soil. In this study, the effects of three types of biochar (corn straw biochar, bamboo charcoal, and pig manure biochar) and pig manure compost fertilizer on ARGs and bacterial community in agriculture soil were compared. It was discovered through pot experiments that the pig manure added with biochar compost will still introduce ARGs into the soil vegetable system. And applying fertilizer with low ARG abundance does not guarantee that the soil system will have low ARGs abundance following fertilization. Corn biochar compost will increase the abundance of pathogenic bacteria (Pseudomonas and Massilia) in soil. In addition, tetC, tetG, tetX, sul1, sul3, and qnrS genes were positively correlated with pathogenic bacteria, posing a health danger to the environment. Bamboo carbon compost will increase the abundance of soil probiotics (Arenimonas), so bamboo carbon compost has more advantages. Our findings have significant implications for the low-risk utilization of pig manure and risk evaluation of pig manure composting fertilizer. [ABSTRACT FROM AUTHOR]

Nanomedicine with high specificity has been a promising tool for cancer diagnosis and therapy. However, the successful application of nanoparticle-based superficial cancer therapy is severely hindered by restricted deep tumor tissue accumulation and penetration. Herein, a self-assembly nanomicelle dissolving microneedle (DMN) patch according to the "nano in micro" strategy was conducted to co-deliver a first-line chemotherapeutic agent paclitaxel (PTX), and a photosensitizer IR780 (PTX/IR780-NMs @DMNs) for chemo-photothermal synergetic melanoma therapy. Upon direct insertion into the tumor site, DMNs created a regular and multipoint three-dimensional drug depot to maximize the tumor accumulation. Accompanied by the DMN dissolution, the composition of the needle matrixes self-assembled into nanomicelles, which could efficiently penetrate deep tumor tissue. Upon laser irradiation, the nanomicelles could not only ablate tumor cells directly by photothermal conversion but also trigger PTX release to induce tumor cell apoptosis. In vivo results showed that compared with intravenous injection, IR780 delivered by PTX/IR780-NMs @DMNs was almost completely accumulated at the tumor site. The antitumor results revealed that the PTX/IR780-NMs @DMNs could effectively eliminate tumors with an 88% curable rate without any damage to normal tissues. This work provides a versatile and generalizable framework for designing self-assembly DMN-mediated combination therapy to fight against superficial cancer. [ABSTRACT FROM AUTHOR]

We aimed to evaluate the effect of Bachmann bundle (BB) impairment on electrical and mechanical function of the left atrium (LA), as well as the long-term clinical impact of such impairment. We measured activation time in the five LA walls in 56 patients with atrial fibrillation. LA reservoir, conduit, and contractile function were also evaluated. Patients were divided into two groups based on ablation strategy: the circumferential pulmonary vein isolation (CPVI) group and CPVI with LA anterior wall linear ablation (LAAW) group. Patients in the CPVI + LAAW group were divided into two sub-groups based on ECG differences following ablation: the BB impairment group and intact BB group. LA activation time and function were then compared between the ablation strategy groups and the CPVI + LAAW subgroups. Patients in the CPVI + LAAW group exhibited longer activation times in the anterior and lateral walls of the LA, poorer LA synchrony, and reduced LA contractile and reservoir function when compared with those in the CPVI group. In the BB impairment subgroup, we observed a discrepancy between electrical/mechanical remodeling. Among five walls, activation time was longest in this region. BB impairment was also associated with reduced LA function. Significant changes in LA function and conductibility were observed in patients with anterior wall ablation, especially those with iatrogenic BB impairment. [ABSTRACT FROM AUTHOR]

Introduction: The critical decision between conservative therapy and surgical intervention to manage cardiac tamponade (CT) during atrial fibrillation (AF) ablation remains empirical. The aim of the study was to summarize the experience in management of CT during AF ablation to derive a proper management pathway.Methods: All patients with CT who underwent catheter ablation for AF in our center from 2013 to 2019 were included.Results: In total of 4887 patients, 32 (0.65%) patients occurred CT and received pericardiocentesis and immediate reversal of anticoagulation. All the CT patients were classified into three groups: rapid and uncontrollable bleeding who needed urgent surgical intervention (4/32), continuous bleeding (14/32), once pericardiocentesis, and no further bleeding (14/32). In the continuous bleeding group, the drainage volume in the first hour after pericardiocentesis was statistically related to surgical repair (p = 0.04) with a cutoff point of 970 ml (AUC 0.84, sensitivity 71.4%, specificity 100%, p = 0.04). During surgical repair, most of perforation sites were detected at superior anterior wall of left atrium close to right or left superior pulmonary vein antrum. No patient died of CT in our cohort.Conclusions: Only a small proportion of patients with CT required surgical intervention during AF ablation. When pericardiocentesis was performed, if a drainage volume was more than 1000 ml in the first hour or bleeding was accelerated after an hour of observation, emergency surgical repair should be recommended. [ABSTRACT FROM AUTHOR]

Background: Pulmonary vein isolation (PVI) has become the cornerstone of atrial fibrillation (AF) ablation, but long-term success rates remains suboptimal, due in large part to late PV reconnection and insufficient ostial substrate modification.Objective: To evaluate whether ablation index (AI)-guided PVI with electrical isolation and quantified ostial substrate modification improves clinical outcomes when compared with contact force (CF)-guided ablation in patients with paroxysmal atrial fibrillation (PAF).Methods: The PAF-AI trial (ChiCTR1900022041) is a prospective, multi-center, randomized controlled clinical trial enrolling patients with PAF with an indication for catheter ablation. Patients are randomized into a 2:1 fashion to two treatment arms: AI-guided PVI (n = 151) and CF-guided PVI (n = 75). In the AI-guided PVI group, real-time automated display of radiofrequency applications (Visitag™) is used with AI ≥ 500 recommended at the anterior/superior/inferior walls and 350-400 at the posterior wall. In CF-guided PVI group, the value and direction of CF are displayed, with the lesion dots manually annotated. The primary endpoint is the freedom from AF recurrence at 12 months following ablation, without antiarrhythmic drug. The primary pre-specified secondary endpoints include intraprocedural efficiency and peri-procedural complications.Conclusions: PAF-AI trial compares the effectiveness and safety of two different strategies of PVI in patients with PAF, AI-guided PVI versus more established CF-guided PVI. This prospective, multi-center, randomized controlled trial, with comparative data evaluating procedural and long-term follow-up results, aims to evaluate the impact of AI-guided strategy on AF ablation compared with the current standard of care RF ablation approach. [ABSTRACT FROM AUTHOR]

Purpose: Sinus node inability or conduction disorders of its surrounding atrial myocardium cause sinus node dysfunction (SND). This study aimed to characterize right atrium (RA) substrates and long-term atrial lead performance after pacemaker implantation in non-senile SND patients.Methods: Eighteen SND patients (53.3 ± 9.6 years) controlled by 18 age-matched supraventricular tachycardia patients were consecutively enrolled. The P-wave amplitude (PWA) and P-wave duration (PWD) were measured on surface electrocardiography. Electroanatomic mapping was conducted to assess the bipolar voltage, complex signals, volume, and activation time of RA. Pacemaker implantation was performed in SND patients after mapping.Results: Compared with controls, SND patients showed significant PWA reduction (0.13 ± 0.02 vs. 0.16 ± 0.04 mV, p = 0.017) and PWD prolongation (120.8 ± 15.2 vs. 105.2 ± 8.6 ms, p = 0.001). The RA endocardial voltage was lower (1.56 ± 0.78 vs. 2.57 ± 0.55 mV, p < 0.001) and activation time was longer (112.1 ± 14.9 vs. 90.8 ± 12.4 ms, p < 0.001) in the study group. Atrial lead was anchored at the lower atrial septum in one patient and failed in another due to extensive atrial scarring. During a median follow-up of 86 (57-88) months, one patient lost atrial capturing, and overall atrial sensing was significantly decreased (2.44 ± 1.16 vs. 1.87 ± 1.01 mV, p = 0.003).Conclusions: Atrial involvement was proved and the process was progressive in non-senile SND patients, as demonstrated by diffused RA lower voltage, slower conduction, and the decrease of the atrial lead sensing. [ABSTRACT FROM AUTHOR]

Mutations in hERG (human ether-à-go-go-related gene) potassium channel are closely associated with long QT syndromes. By direct Sanger sequencing, we identified a novel KCNH2 mutation W410R in the patient with long QT syndrome 2 (LQT2). However, the electrophysiological functions of this mutation remain unknown. In comparison to hERGWT channels, hERGW410R channels have markedly decreased total and surface expressions. W410R mutation dramatically reduces hERG channel currents (IKr) and shifts its steady-state activation curve to depolarization. Moreover, hERGW410R channels make dominant-negative effects on hERGWT channels. Significantly, we find hERG channel blocker E-4031 could partially rescue the function of hERGW410R channels by increasing the membrane expression. By using in silico model, we reveal that hERGW410R channels obviously elongate the repolarization of human ventricular myocyte action potentials. Collectively, W410R mutation decreases the currents of hERG channel, because of diminished membrane expression of mutant channels, that subsequently leads to elongated repolarization of cardiomyocyte, which might induce the pathogenesis of LQT2. Furthermore, E-4031 could partially rescue the decreased activity of hERGW410R channels. Thus, our work identifies a novel loss-of-function mutation in KCNH2 gene, which might provide a rational basis for the management of LQT2. [ABSTRACT FROM AUTHOR]

Background: Re-ablation has an important role in the control of recurrent atrial fibrillation (AF) post the first ablation. The present study was to report the outcome of AF re-ablation for patients who recurred after initial ablation, and to characterize the clinical and electrophysiological features predicting recurrence after redo ablation.Methods: From January 2012 to May 2017, patients undergoing re-ablation for AF in our hospital were consecutively enrolled. Clinical and electrophysiological data for the initial and second procedure were collected retrospectively and prospectively, respectively. All patients were followed up for one year and recurrences during the time were reported.Results: Totally 259 patients entered into the analysis (age, 58.4 ± 10.5 years; 169 men). At the end of one-year follow-up, 85 patients recurred with atrial arrhythmias (32.8%). In the multivariate analysis, higher CHA2DS2-VASC score (p = 0.023, 95% CI 1.03-1.53) and shorter time to recurrence after the initial ablation (p = 0.001, 95% CI 0.93-0.98) were clinical factors predictive of one-year recurrence after the repeat ablation. The reconnection of the right pulmonary vein (PV) (p = 0.034, 95% CI 0.31-0.96) and the absence of not eliminated non-PV trigger at the second procedure (p = 0.032, 95% CI 1.25-142.80) independently predicted the better re-ablation outcome.Conclusions: About one-third of patients recurred after one year following re-ablation. CHA2DS2-VASC score and time to recurrence after the initial ablation were independent clinical factors predicting recurrence. Also, electrophysiological findings during the repeat ablation (the right PV reconnection and absence of not eliminated non-PV trigger) were associated with better outcome during one year of follow-up. [ABSTRACT FROM AUTHOR]

Ventricular arrhythmias are an important cause of morbidity and mortality and come in a variety of forms, from single premature ventricular complexes to sustained ventricular tachycardia and fibrillation. Rapid developments have taken place over the past decade in our understanding of these arrhythmias and in our ability to diagnose and treat them. The field of catheter ablation has progressed with the development of new methods and tools, and with the publication of large clinical trials. Therefore, global cardiac electrophysiology professional societies undertook to outline recommendations and best practices for these procedures in a document that will update and replace the 2009 EHRA/HRS Expert Consensus on Catheter Ablation of Ventricular Arrhythmias. An expert writing group, after reviewing and discussing the literature, including a systematic review and meta-analysis published in conjunction with this document, and drawing on their own experience, drafted and voted on recommendations and summarized current knowledge and practice in the field. Each recommendation is presented in knowledge byte format and is accompanied by supportive text and references. Further sections provide a practical synopsis of the various techniques and of the specific ventricular arrhythmia sites and substrates encountered in the electrophysiology lab. The purpose of this document is to help electrophysiologists around the world to appropriately select patients for catheter ablation, to perform procedures in a safe and efficacious manner, and to provide follow-up and adjunctive care in order to obtain the best possible outcomes for patients with ventricular arrhythmias. [ABSTRACT FROM AUTHOR]

Background: The role of catheter ablation as an adjunct and alternative to ICD implantation is not known in patients at risk for recurrent ventricular tachycardia (VT) and sudden cardiac death (SCD) across Asia. Patients with nonischemic etiologies of cardiomyopathy, which are highly prevalent in Asia, have not been previously enrolled in randomized trials of VT ablation.Objective: To evaluate whether preemptive catheter ablation in patients with monomorphic VT and an indication for ICD implantation results in improved clinical outcomes compared to ICD implantation with standard medical therapy alone. To examine the natural history of ablation outcomes in the absence of background ICD therapy in patients that refuse randomization.Methods: The PAUSE-SCD study (NCT02848781) is a prospective, multi-center, randomized controlled trial enrolling patients with structural heart disease (EF < 50%) with an indication for ICD implantation. Patients are randomized in a 1:1 fashion to two treatment arms: ICD with ablation and ICD with standard medical therapy alone. A prospective registry cohort was designed to follow the outcomes of patients who refuse ICD and randomization but elect to receive catheter ablation as primary therapy. The primary endpoint is defined as a composite of recurrent VT, cardiovascular rehospitalization, and death. Pre-specified secondary endpoints include each of the individual components of the primary endpoint in addition to comparison between randomized and registry patients.Conclusion: The PAUSE-SCD study is a prospective, multi-center, randomized, and controlled trial examining the impact of preemptive catheter ablation on cardiovascular outcomes in patients with an indication for ICD at risk for recurrent VT and SCD. It represents the first multi-center VT ablation study in Asia, with a design intended to provide insights into the role of both ICD and ablation therapy in a predominantly nonischemic population. [ABSTRACT FROM AUTHOR]

Particulate matter (PM) is one of the most important environmental issues worldwide, which is associated with not only pulmonary but also cardiovascular diseases. However, the underlying biological mechanisms of PM related cardiovascular dysfunction remained poorly defined, especially mediated by the pathway of direct impact on vascular and heart. Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) provide an ideal platform for studying PM-exposed cellular diseases model in vitro. Here, we investigated the direct effects of particulate matter 2.5 (PM2.5) on hiPSC-CMs and the potential mechanism at non-cytotoxic concentrations. Cell viability, contraction amplitude and spontaneous beating rate of iPSC-CMs after direct exposure to PM2.5 showed that the concentration of lower than 100 µg/ml would not lead to cytotoxic effects. Calcium-mediated optical mapping illustrated that there was a concentration-dependent reduction in quantification of calcium transient amplitude and an increase in the incidence of early after depolarizations due to PM2.5 treatment. Furthermore, there were dramatic dosage-dependent shortening in action potential duration and decrease in L-type calcium peak current density. The Ingenuity Pathway Analysis of our transcriptive study indicated that PM2.5 exposure preferentially influenced the expression of genes involved in calcium signaling. Among them the up-regulation of TRPC3 potentially played an important role in the electrophysiological alteration of PM2.5 on hiPSC-CMs, which could be ameliorated by pretreatment with pyr3, the inhibitor of TRPC3. In conclusion, our results demonstrated that exposure to PM2.5 was capable of increasing propensity to cardiac arrhythmias which could be attenuated with TRPC3 inhibition. [ABSTRACT FROM AUTHOR]

Purpose: Late cure after a previously failed ablation of ventricular arrhythmias (VAs) is a relatively common phenomenon. The present study sought to delineate the incidence and electrophysiological characteristics of late cure in idiopathic VA patients.Methods: Totally, 45 idiopathic VA cases (mean age 44 ± 18 years, 27 males) either failed acutely or recurred within 12 h were enrolled in this study. Based on intensive clinical observations in the acute period, 19 (42%) patients demonstrated late cure in the first week after the procedure.Results: The late cure patients had significantly better acute and cumulative ablation effects during the procedure than did those without a late cure. Additionally, they had a prediction that originated from the right ventricular outflow tract, aortic-mitral continuum, and left summit area relative to other sites (13/18 vs 6/27, p < 0.01). In a median follow-up of 24 [14, 46] months, 7/19 (37%) patients had their VAs recurred. The late cure group had significantly more patients cured at long-term follow-up than those without (12/19 vs 0/26, p < 0.01). A cutoff value of the "time to eliminate VAs" > 7.0 s was able to predict a long-term recurrence of the VAs with 62.5% sensitivity and 85.7% specificity.Conclusions: The late cure of VAs occurs in more than one third of patients who have a seemingly unsuccessful ablation session, which is clustered in the first week after the procedure. However, long-term recurrence of VAs occurred in 37% of the late cure patients, emphasizing the importance of long-term follow-up. [ABSTRACT FROM AUTHOR]

The Nav-star ablation catheter (Biosense Webster) was introduced to the functional pulmonary artery, and the radiofrequency energy was delivered nearby the HIS region; the tachycardia was terminated after 12 s and the junctional response was observed during ablation; however, the tachycardia could be re-induced. A 36-year-old man with a previous diagnosed corrected transposition of the great vessels (CTGV) was referred with a 6-year history of frequent episodes of palpitations with sudden onset and offset. AAVNRT, atypical atrioventricular nodal reentrant tachycardia; TCL, tachycardia cycle length Funding This study was funded by the Special Foundation for Clinical Science and Technology of Jiangsu Province [BE2017754]. [Extracted from the article]

Purpose: Monitoring of response to neoadjuvant chemotherapy (NCT) is important for optimal management of patients with breast cancer. Tc-3PRGD SPECT is a newly developed imaging modality for evaluating tumor vascular status. In this study, we investigated the application of Tc-3PRGD SPECT in evaluating therapy response to NCT in patients with stage II or III breast cancer. Methods: Thirty-three patients were scheduled to undergo Tc-3PRGD SPECT at baseline, after the first and second cycle of NCT. Four patients had extremely low Tc-3PRGD uptake at baseline, and were not included in the subsequent studies. Changes in tumor to nontumor (T/N) ratio were compared with pathological tumor responses classified using the residual cancer burden system. Receiver operator characteristic analysis was used to compare the power to identify responders between the end of the first and the end of the second cycle of NCT. The impact of breast cancer subtype on Tc-3PRGD uptake was evaluated. The correlation between Tc-3PRGD uptake and pathological tumor response was also evaluated in each breast cancer subtype. Results: Surgery was performed after four cycles of NCT and pathological analysis revealed 18 responders and 15 nonresponders. In patients with clearly visible Tc-3PRGD uptake at baseline, the sensitivity, specificity, and negative predictive value of Tc-3PRGD SPECT were 86.7 %, 85.7 % and 86.7 % after the first cycle of NCT, and 92.9 %, 93.3 % and 93.3 % after the second cycle, respectively. Among these patients, the HER-2-positive group demonstrated both higher T/N ratios and a greater change in T/N ratio than patients with other breast cancer subtypes ( P < 0.05). A strong correlation was found between changes in T/N ratio and pathological tumor response in the HER-2-positive group ( P < 0.03). Conclusion: Tc-3PRGD SPECT seems to be useful for determining the pathological tumor response in patients with stage II or III breast cancer undergoing NCT, especially those with the HER-2-positive subtype. [ABSTRACT FROM AUTHOR]

Induced pluripotent stem cells (iPSc) hold significant promise for the development of cardiac regenerative therapy for myocardial infarction (MI). However, preclinical optimization and validation of large-animal models will be required before iPSc used clinically. Therefore, we aim to investigate the therapeutic potential of iPSc transplantation for MI and relative mechanisms in a post-infarcted swine model. Left anterior descending coronary artery was balloon-occluded after percutaneous transluminal angiography to generate MI (60-min no-flow ischemia). Animals were then divided into Sham, PBS control, and iPS experimental groups. The cardiac function and LV structural were assessed by dual-source computed tomography. Terminal deoxynucleotidyl nick end labeling, histology, and immunofluorescence were used to examine the effect of transplanted iPS cells on apoptosis, fibrosis, and hypertrophy. At 6 weeks, LV structural abnormality and cardiac dysfunction were less pronounced in iPSc group than in PBS group, and these improvements were accompanied by reduction of scar size. iPSc transplantation was associated with significant increase of vascular density and reduced myocardial apoptosis in the border zone of infarction, which was accompanied by the reduction in fibrosis degree. Moreover, proangiogenic and antiapoptotic factors were increased significantly in iPS group compared with PBS group. Cardiomyocyte hypertrophy was significantly attenuated by iPSc transplantation. In conclusion, these results suggested that transplantation of iPSc may result in functional recovery by promoting angiogenesis, inhibiting apoptosis, and ameliorating cardiac remodeling. This proof of concept study may provide a basis for an autologous iPSc-based therapy of MI. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study is to explore the left atrium (LA) electrophysiologic abnormalities in atrial fibrillation (AF) patients detected during sinus rhythm and to determine the relationship between the type of AF and the electrophysiologic substrate in the LA. Methods: Eighty patients with AF (30 paroxysmal AF, 22 persistent AF, and 28 long-standing AF) and 20 age- and sex-matched patients with left-sided accessory pathway were prospectively studied. High-density three-dimensional electroanatomic mapping was performed during sinus rhythm in LA, which was divided into six segments for regional analysis. Mean bipolar voltage, low voltage zone (LVZ) distribution, LA activation time, and electrogram complexity were assessed. Results: The LA mean voltage was 3.67 ± 0.68 mV in no AF group, 2.16 ± 0.63 mV in the paroxysmal, 1.81 ± 0.36 mV in the persistent, and 1.48 ± 0.34 mV in the long-standing AF patients ( P < 0.001). The total LA activation time was 75.3 ± 5.4 ms in no AF, 89.7 ± 12.3 ms in paroxysmal AF, 104.9 ± 6.1 ms in persistent AF, and 115.6 ± 12.1 ms in the long-standing AF patients, respectively ( P < 0.001). With the progression of AF, there was a higher incidence of LVZ detection and increased prevalence of complex electrograms with 95 % of complex electrograms in areas with the bipolar voltage ≤ 1.3 mV in persistent and long-standing AF patients. Conclusion: Patients with AF have abnormal electrophysiologic substrate in sinus rhythm characterized by lower mean bipolar voltage, more prevalent complex electrograms, and longer LA activation time. This substrate progresses parallel to progression of AF type. [ABSTRACT FROM AUTHOR]

Background: A remote magnetic navigation system (MNS) has been developed for mapping and catheter ablation of cardiac arrhythmias. The present study evaluates the safety and feasibility of this system to perform radiofrequency (RF) ablation in patients with supraventricular tachycardias (SVT).Methods: A total of 32 patients (22 female; mean age 44 +/- 16 years) with documented SVT underwent mapping and ablation using Helios II (a 4-mm-tip magnetic catheter), under the guidance of the MNS (Niobe II, Stereotaxis, Inc.).Results: Catheter ablation procedure with MNS was successful in 30/32 (94%) patients including all patients (27/27, 100%) with atrioventricular nodal reentrant tachycardia (AVNRT) and three of five patients (60%) with atrioventricular reentrant tachycardia (AVRT) without any complication. The procedural successful rate in patients with AVNRT was significantly higher than those in patients with AVRT (P < 0.001). Overall, the medium number of RF application using the MNS was 2 (mean 2.7 +/- 1.6, range 1 to 7), and the medium numbers of RF for AVNRT and AVRT were 2 and 3, respectively. There was no significant difference in the mean procedural time between patients with AVNRT and AVRT (126.3 +/- 38.6 vs. 138.0 +/- 40.3 min, P = 0.54). However, the mean fluoroscopy time was significantly shorter in patients with AVNRT than those with AVRT (5.7 +/- 3.0 vs. 16.5 +/- 2.5 min, P < 0.001). Among those patients with AVNRT, the mean procedural time (139.3 +/- 45.0 vs. 112.3 +/- 24.9 min, P = 0.07) and fluoroscopic time (3.2 +/- 1.0 vs. 8.0 +/- 2.2 min, P < 0.001) were shorter for the later 13 patients than the first 14 patients, suggesting a learning curve in using the MNS for RF ablation.Conclusions: The Niobe MNS is a new technique that can allow safe and effective remote-controlled navigation and minimize the need for fluoroscopic guidance for ablation catheter of AVNRT. However, further improvement is required to achieve a higher successful rate for treatment of AVRT. [ABSTRACT FROM AUTHOR]

A 30-year-old man presented with narrow QRS tachycardia. The intracardiac electrocardiogram showed an atrial-HIS (AH) interval of 75 msec and a HIS-ventricular (HV) interval of 44 msec during baseline. Atrial incremental pacing revealed HV shortening, with apparent incomplete right bundle branch block (RBBB) morphology without QRS complex axis deviation. The induced tachycardia exhibited several QRS morphologies: a narrow QRS, complete RBBB and complete left bundle branch block (LBBB) morphology. Spontaneous conversion of the QRS pattern from wide to narrow was observed. The cycle length of the tachycardia was significantly shortened (from 316 to 272 ms) from LBBB morphology to narrow QRS complex. The atrial activation was dissociated from the ventricular activation during all tachycardias. Each QRS complex during tachycardia was preceded by a HIS deflection and HV interval was 35 ms, which was shorter than that of sinus rhythm. HIS deflection was earlier than right bundle potential during all kinds of tachycardia. This tachycardia is most likely mediated by a left fasciculoventricular fiber which connects the HIS bundle below the atrioventricular node to the myocardial tissue of the left ventricle. The HIS-Purkinje system is used as an antegrade conduction limb and the fasciculoventricular fiber as a retrograde limb in the tachycardia circuit. [ABSTRACT FROM AUTHOR]

Background: Ablation of ventricular tachycardias in arrhythmogenic right ventricular dysplasia (ARVD-VTs) still remains a clinical challenge. We reported the value of abnormal electrophysiological substrate mapping for guiding ablation of ARVD-VTs using a non-contact mapping system.Methods and Results: Dynamic substrate mapping was performed in three male ARVD patients during sinus rhythm. The sites of earliest activation, exit point and activation sequence were mapped for each induced VT. Three different patterns of substrates were determined in 3 patients and located in right ventricular outflow tract, anterior right ventricular wall, and anterolateral right ventricular wall, respectively. Five different clinical VTs (mean CL, 348 +/- 65 ms) were induced. Of 5 VTs, three originated from or near the boundary of substrate, and two had a remote origin. One VT conducted through the substrate. Linear ablations were created between the sites of the earliest ventricular activation and the VT exit point, or across the critical isthmus. The five clinical VTs were successfully ablated with a median of 17 radiofrequency applications. One patient was treated with amiodarone for a VT not clinically observed. There were no VT recurrences during 8.6 months of follow-up.Conclusions: Defining the abnormal anatomical VT substrates is useful for understanding the mechanisms of ARVD-VTs and determining an ablation strategy. Linear ablation across a critical isthmus or between the early activation and the exit point can effectively cure these arrhythmias. [ABSTRACT FROM AUTHOR]

During the course of writing and revision of this paper, the authorship changed. Min Ling, M.S. and Qian Bian, Ph.D., are added in the list of authors. [ABSTRACT FROM AUTHOR]

Plaque erosion (PE) with secondary thrombosis is one of the key mechanisms of acute coronary syndrome (ACS) which often leads to drastic cardiovascular events. Identification and prediction of PE are of fundamental significance for disease diagnosis, prevention and treatment. In vivo optical coherence tomography (OCT) data of eight eroded plaques and eight non-eroded plaques were acquired to construct three-dimensional fluid–structure interaction models and obtain plaque biomechanical conditions for investigation. Plaque stenosis severity, plaque burden, plaque wall stress (PWS) and strain (PWSn), flow shear stress (FSS), and ΔFSS (FSS variation in time) were extracted for comparison and prediction. A logistic regression model was used to predict plaque erosion. Our results indicated that the combination of mean PWS and mean ΔFSS gave best prediction (AUC = 0.866, 90% confidence interval (0.717, 1.0)). The best single predictor was max ΔFSS (AUC = 0.819, 90% confidence interval (0.624, 1.0)). The average of maximum FSS values from eroded plaques was 76% higher than that from the non-eroded plaques (127.96 vs. 72.69 dyn/cm2) while the average of mean FSS from erosion sites of the eight eroded plaques was 48.6% higher than that from sites without erosion (71.52 vs. 48.11 dyn/cm2). The average of mean PWS from plaques with erosion was 22.83% lower than that for plaques without erosion (83.2 kPa vs. 107.8 kPa). This pilot study suggested that combining plaque stress, strain and flow shear stress could help better identify patients with potential plaque erosion, enabling possible early intervention therapy. Further studies are needed to validate our findings. [ABSTRACT FROM AUTHOR]