Left bundle branch pacing set to outshine biventricular pacing for cardiac resynchronization therapy?

The deleterious effects of long-term right ventricular pacing necessitated the search for alternative pacing sites which could prevent or alleviate pacinginduced cardiomyopathy.Until recently,biventricular pacing(BiVP)was the only modality which could mitigate or prevent pacing induced dysfunction.Further,BiVP could resynchronize the baseline electromechanical dssynchrony in heart failure and improve outcomes.However,the high non-response rate of around 20%-30%remains a major limitation.This non-response has been largely attributable to the direct non-physiological stimulation of the left ventricular myocardium bypassing the conduction system.To overcome this limitation,the concept of conduction system pacing(CSP)came up.Despite initial success of the first CSP via His bundle pacing(HBP),certain drawbacks including lead instability and dislodgements,steep learning curve and rapid battery depletion on many occasions prevented its widespread use for cardiac resynchronization therapy(CRT).Subsequently,CSP via left bundle branch-area pacing(LBBP)was developed in 2018,which over the last few years has shown efficacy comparable to BiVP-CRT in small observational studies.Further,its safety has also been well established and is largely free of the pitfalls of the HBP-CRT.In the recent metanalysis by Yasmin et al,comprising of 6 studies with 389 participants,LBBPCRT was superior to BiVP-CRT in terms of QRS duration,left ventricular ejection fraction,cardiac chamber dimensions,lead thresholds,and functional status amongst heart failure patients with left bundle branch block.However,there are important limitations of the study including the small overall numbers,inclusion of only a single small randomized controlled trial(RCT)and a small follow-up duration.Further,the entire study population analyzed was from China which makes generalizability a concern.Despite the concerns,the meta-analysis adds to the growing body of evidence demonstrating the efficacy of LBBP-CRT.At this stage,one must acknowledge that the fact that still our opinions on this technique are largely based on observational data and there is a dire need for larger RCTs to ascertain the position of LBBPCRT in management of heart failure patients with left bundle branch block.

Left bundle branch pacing vs biventricular pacing in heart failure patients with left bundle branch block:A systematic review and meta-analysis

BACKGROUND Left bundle branch pacing(LBBP)is a novel pacing modality of cardiac resynchronization therapy(CRT)that achieves more physiologic native ventricular activation than biventricular pacing(BiVP).AIM To explore the validity of electromechanical resynchronization,clinical and echocardiographic response of LBBP-CRT.METHODS Systematic review and Meta-analysis were conducted in accordance with the standard guidelines as mentioned in detail in the methodology section.RESULTS In our analysis,the success rate of LBBP-CRT was determined to be 91.1%.LBBP CRT significantly shortened QRS duration,with significant improvement in echocardiographic parameters,including left ventricular ejection fraction,left ventricular end-diastolic diameter and left ventricular end-systolic diameter in comparison with BiVP-CRT.CONCLUSION A significant reduction in New York Heart Association class and B-type natriuretic peptide levels was also observed in the LBBP-CRT group vs BiVP-CRT group.Lastly,the LBBP-CRT cohort had a reduced pacing threshold at follow-up as compared to BiVP-CRT.

COMPLETE KAHLER METRICS WITH POSITIVE HOLOMORPHIC SECTIONAL CURVATURES ON CERTAIN LINE BUNDLES(RELATED TO A COHOMOGENEITY ONE POINT OF VIEW ON A YAU CONJECTURE)

In this article,we study Kahler metrics on a certain line bundle over some compact Kahler manifolds to find complete Kahler metrics with positive holomorphic sectional(or bisectional)curvatures.Thus,we apply a strategy to a famous Yau conjecture with a co-homogeneity one geometry.

Left bundle branch area pacing combined with implantable cardioverter-defibrillator treatment for heart failure after myocardial infarction

Left bundle branch area pacing(LBBAP)has emerged as a new physiological pacing mode.Previous studies have confirmed the feasibility and efficacy of LBBAP for cardiac resynchronization therapy(CRT)in heart failure(HF)patients with left bundle branch block(LBBB)and a narrower QRS duration(QRSd)to have a higher percentage of super responders,and lower pacing thresholds than biventricular pacing(BiVP).

A new interacting capillary bundle model on the multiphase flow in micropores of tight rocks

Surfactants are widely used in the fracturing fluid to enhance the imbibition and thus the oil recovery rate. However, current numerical models cannot capture the physics behind capillary imbibition during the wettability alteration by surfactants. Although the interacting capillary bundle(ICB) model shows potential in characterizing imbibition rates in different pores during wettability alteration, the existing ICB models neglect the influence of wettability and viscosity ratio on the imbibition behavior, making it difficult to accurately describe the oil-water imbibition behavior within the porous media. In this work,a new ICB mathematical model is established by introducing pressure balance without assuming the position of the leading front to comprehensively describe the imbibition behavior in a porous medium under different conditions, including gas-liquid spontaneous imbibition and oil-water imbibition.When the pore size distribution of a tight rock is known, this new model can predict the changes of water saturation during the displacement process in the tight rock, and also determine the imbibition rate in pores of different sizes. The water saturation profiles obtained from the new model are validated against the waterflooding simulation results from the CMG, while the imbibition rates calculated by the model are validated against the experimental observations of gas-liquid spontaneous imbibition. The good match above indicates the newly proposed model can show the water saturation profile at a macroscopic scale while capture the underlying physics of the multiphase flow in a porous medium at a microscopic scale. Simulation results obtained from this model indicate that both wettability and viscosity ratio can affect the sequence of fluid imbibition into pores of different sizes during the multiphase flow, where less-viscous wetting fluid is preferentially imbibed into larger pores while more-viscous wetting fluid tends to be imbibed into smaller pores. Furthermore, this model provides an avenue to calculate the imbibition rate in pores of different sizes during wettability alteration and capture the non-Darcy effect in micro-and nano-scale pores.

Fiber Bundle Topology Optimization for Surface Flows

This paper presents a topology optimization approach for the surface flows on variable design domains.Via this approach,the matching between the pattern of a surface flow and the 2-manifold used to define the pattern can be optimized,where the 2-manifold is implicitly defined on another fixed 2-manifold named as the base manifold.The fiber bundle topology optimization approach is developed based on the description of the topological structure of the surface flow by using the differential geometry concept of the fiber bundle.The material distribution method is used to achieve the evolution of the pattern of the surface flow.The evolution of the implicit 2-manifold is realized via a homeomorphous map.The design variable of the pattern of the surface flow and that of the implicit 2-manifold are regularized by two sequentially implemented surface-PDE filters.The two surface-PDE filters are coupled,because they are defined on the implicit 2-manifold and base manifold,respectively.The surface Navier-Stokes equations,defined on the implicit 2-manifold,are used to describe the surface flow.The fiber bundle topology optimization problem is analyzed using the continuous adjoint method implemented on the first-order Sobolev space.Several numerical examples have been provided to demonstrate this approach,where the combination of the viscous dissipation and pressure drop is used as the design objective.

专业Bundles策略护理在骨折合并脾脏损伤护理中的应用价值

目的:探讨与分析专业Bundles策略护理在骨折合并脾脏损伤护理中的应用价值.方法:选择2021年2月—2023年2月我院收治的76例骨折合并脾脏损伤患者为研究对象,根据随机信封抽签1∶1原则将其分为Bundles组与对照组,各38例.对照组在围手术期实施常规护理,Bundles组在对照组基础上给予围手术期专业Bundles策略护理,2组护理观察时间均为14 d.记录2组患者的预后恢复、心理变化、并发症与护理满意度情况.结果:Bundles组术中出血量少于对照组,手术时间、术后肛门排气时间、术后肛门排便时间、术后下床活动时间、术后住院时间均短于对照组,组间差异有统计学意义(P<0.05);护理14 d后,2组SDS、SAS评分均低于护理前,且Bundles组低于对照组,差异有统计学意义(P<0.05);Bundles组并发症发生率低于对照组,差异有统计学意义(P<0.05);Bundles组护理满意度高于对照组,差异有统计学意义(P<0.05).结论:专业Bundles策略护理在骨折合并脾脏损伤护理中的应用能促进患者康复,可减少创伤,缓解患者的焦虑与抑郁情绪,并且还能提高安全性,减少不良事件的发生,患者更加满意.

Optimized CUDA Implementation to Improve the Performance of Bundle Adjustment Algorithm on GPUs

The 3D reconstruction pipeline uses the Bundle Adjustment algorithm to refine the camera and point parameters. The Bundle Adjustment algorithm is a compute-intensive algorithm, and many researchers have improved its performance by implementing the algorithm on GPUs. In the previous research work, “Improving Accuracy and Computational Burden of Bundle Adjustment Algorithm using GPUs,” the authors demonstrated first the Bundle Adjustment algorithmic performance improvement by reducing the mean square error using an additional radial distorting parameter and explicitly computed analytical derivatives and reducing the computational burden of the Bundle Adjustment algorithm using GPUs. The naïve implementation of the CUDA code, a speedup of 10× for the largest dataset of 13,678 cameras, 4,455,747 points, and 28,975,571 projections was achieved. In this paper, we present the optimization of the Bundle Adjustment algorithm CUDA code on GPUs to achieve higher speedup. We propose a new data memory layout for the parameters in the Bundle Adjustment algorithm, resulting in contiguous memory access. We demonstrate that it improves the memory throughput on the GPUs, thereby improving the overall performance. We also demonstrate an increase in the computational throughput of the algorithm by optimizing the CUDA kernels to utilize the GPU resources effectively. A comparative performance study of explicitly computing an algorithm parameter versus using the Jacobians instead is presented. In the previous work, the Bundle Adjustment algorithm failed to converge for certain datasets due to several block matrices of the cameras in the augmented normal equation, resulting in rank-deficient matrices. In this work, we identify the cameras that cause rank-deficient matrices and preprocess the datasets to ensure the convergence of the BA algorithm. Our optimized CUDA implementation achieves convergence of the Bundle Adjustment algorithm in around 22 seconds for the largest dataset compared to 654 seconds for the sequential implementation, resulting in a speedup of 30×. Our optimized CUDA implementation presented in this paper has achieved a 3× speedup for the largest dataset compared to the previous naïve CUDA implementation.

Selective his bundle pacing eliminates crochetage sign:A case report

BACKGROUND Crochetage sign is a specific electrocardiographic manifestation of ostium secundum atrial septal defects(ASDs),which is associated with the severity of the left-to-right shunt.Herein,we reported a case of selective his bundle pacing(SHBP)that eliminated crochetage sign in a patient with ostium secundum ASD.CASE SUMMARY A 77-year-old man was admitted with a 2-year history of chest tightness and shortness of breath.Transthoracic echocardiography revealed an ostium secundum ASD.Twelve-lead electrocardiogram revealed atrial fibrillation with a prolonged relative risk interval,incomplete right bundle branch block,and crochetage sign.The patient was diagnosed with an ostium secundum ASD,atrial fibrillation with a second-degree atrioventricular block,and heart failure.The patient was treated with selective his bundle pacemaker implantation.After the procedure,crochetage sign disappeared during his bundle pacing on the electrocardiogram.CONCLUSION S-HBP eliminated crochetage sign on electrocardiogram.Crochetage sign may be a manifestation of a conduction system disorder.

Left bundle branch area pacing:A new era of cardiac resynchronization therapy?

The recent systematic review and meta-analysis provided a comprehensive focus on the current state of cardiac resynchronization therapy(CRT).The authors determined the feasibility of physiological left bundle branch area pacing(LBBAP)in patients indicated for CRT through a careful analysis of trials.They found that LBBAP was associated with significant reductions in QRS duration,New York Heart Association functional class,B-type natriuretic peptide levels,and pacing thresholds as well as improvements in echocardiographic parameters compared to biventricular pacing.

Improving pressure ulcer care in intensive care units:Evaluating the impact of bundled care and silver nanoparticle dressings

BACKGROUND Pressure ulcer(PU)are prevalent among critically ill trauma patients,posing substantial risks.Bundled care strategies and silver nanoparticle dressings offer potential solutions,yet their combined effectiveness and impact on patient satisfaction remain insufficiently investigated.AIM To assess the impact of bundled care along with silver nanoparticle dressing on PUs management and family satisfaction in critically ill trauma patients.METHODS A total of 98 critically ill trauma patients with PUs in intensive care unit(ICU)were included in this study.Patients were randomly assigned to either the control group(conventional care with silver nanoparticle dressing,n=49)or the intervention group(bundled care with silver nanoparticle dressing,n=49).The PU Scale for Healing(PUSH)tool was used to monitor changes in status of pressure injuries over time.Assessments were conducted at various time points:Baseline(day 0)and subsequent assessments on day 3,day 6,day 9,and day 12.Family satisfaction was assessed using the Family Satisfaction ICU 24 ques-tionnaire.RESULTS No significant differences in baseline characteristics were observed between the two groups.In the intervention group,there were significant reductions in total PUSH scores over the assessment period.Specifically,surface area,exudate,and tissue type parameters all showed significant improvements compared to the control group.Family satisfaction with care and decision-making was notably higher in the intervention group.Overall family satisfaction was significantly better in the intervention group.CONCLUSION Bundled care in combination with silver nanoparticle dressings effectively alleviated PUs and enhances family satisfaction in critically ill trauma patients.This approach holds promise for improving PUs management in the ICU,benefiting both patients and their families.

Analysis of The Effect of Bundled Nursing Intervention on Lung Cancer Patients with a High Risk of PICC-Related Thrombosis

Objective: To explore the effect of bundled nursing intervention on lung cancer patients with a high risk of PICC-related thrombosis. Methods: Eighty-six PICC patients were selected and randomly divided into a control group and an observation group of 43 patients each. The control group received general nursing care and the observation group received bundled nursing intervention based on the control group. The occurrence of venous thrombosis, quality of life score, Zung self-rating depression scale (SDS) score, self-rating anxiety (SAS) score, and nursing satisfaction after treatment were compared between the two groups. Results: The incidence rate of PICC-related venous thrombosis in the observation group (2/4.652%) was lower than that of the control group (13/30.231%) after nursing intervention (P < 0.05). After the intervention, the quality-of-life scores of the observation group were higher than those of the control group (P < 0.001). After the intervention, the SDS and SAS scores of the observation group were lower than those of the control group (P < 0.001). The nursing satisfaction rate of the observation group (41/ 4.652%) was higher than that of the control group (35/18.604%) (P < 0.05). The difference is statistically significant. Conclusion: In the care of lung cancer patients with a high risk of PICC-related thrombosis, bundled nursing care achieved better results.

TD-LTE终端协议栈TTI Bundling方案的实现

TD-LTE系统中小区边缘终端的信道质量较差,为了达到较好的上行覆盖LTE提出了TTIBundling技术。通过研究3GPP TD-LTE协议中物理层协议和MAC协议,归纳出TTI Bunding模式在不同的上下行配比帧结构上HARQ进程相关连的授权、发送和基站反馈间的时序关系。TTI Bundling实现是基于TD-LTE不同配比下的帧结构时序关系。最后以TD-LTE协议栈为基础,使用规范和描述语言(SDL)/数表结合仿真法(TTCN)实现该功能。

His bundle pacing versus left bundle branch pacing on ventricular function in atrial fibrillation patients referred for pacing:a prospective crossover comparison

BACKGROUND His bundle pacing(HBP)and left bundle branch pacing(LBBP)both provide physiologic pacing which maintain left ventricular synchrony.They both improve heart failure(HF)symptoms in atrial fibrillation(AF)patients.We aimed to assess the intra-patient comparison of ventricular function and remodeling as well as leads parameters corresponding to two pacing modalities in AF patients referred for pacing in intermediate term.METHODS Uncontrolled tachycardia AF patients with both leads implantation successfully were randomized to either modality.Echocardiographic measurements,New York Heart Association(NYHA)classification,quality-of-life assessments and leads parameters were obtained at baseline and at each 6-month follow up.Left ventricular function including the left ventricular endosystolic volume(LVESV),left ventricular ejection fraction(LVEF)and right ventricular(RV)function quantified by tricuspid annular plane systolic excursion(TAPSE)were all assessed.RESULTS Consecutively twenty-eight patients implanted with both HBP and LBBP leads successfully were enrolled(69.1±8.1 years,53.6% male,LVEF 59.2%±13.7%).The LVESV was improved by both pacing modalities in all patients(n=23)and the LVEF was improved in patients with baseline LVEF at less than 50%(n=6).The TAPSE was improved by HBP but not LBBP(n=23).CONCLUSION In this crossover comparison between HBP and LBBP,LBBP was found to have an equivalent effect on LV function and remodeling but better and more stable parameters in AF patients with uncontrolled ventricular rates referred for atrioventricular node(AVN)ablation.HBP could be preferred in patients with reduced TAPSE at baseline rather than LBBP.

MAXWELL-EINSTEIN METRICS ON COMPLETIONS OF CERTAIN C* BUNDLES

In this paper,we prove that for some completions of certain fiber bundles there is a Maxwell-Einstein metric conformally related to any given Kahler class.

Model-based deep learning for fiber bundle infrared image restoration

As the representative of flexibility in optical imaging media,in recent years,fiber bundles have emerged as a promising architecture in the development of compact visual systems.Dedicated to tackling the problems of universal honeycomb artifacts and low signal-to-noise ratio(SNR)imaging in fiber bundles,the iterative super-resolution reconstruction network based on a physical model is proposed.Under the constraint of solving the two subproblems of data fidelity and prior regularization term alternately,the network can efficiently“regenerate”the lost spatial resolution with deep learning.By building and calibrating a dual-path imaging system,the real-world dataset where paired low-resolution(LR)-high-resolution(HR)images on the same scene can be generated simultaneously.Numerical results on both the United States Air Force(USAF)resolution target and complex target objects demonstrate that the algorithm can restore high-contrast images without pixilated noise.On the basis of super-resolution reconstruction,compound eye image composition based on fiber bundle is also embedded in this paper for the actual imaging requirements.The proposed work is the first to apply a physical model-based deep learning network to fiber bundle imaging in the infrared band,effectively promoting the engineering application of thermal radiation detection.

Bundles策略在预防全麻患者术中低体温中的应用

目的:探讨Bundles策略在预防全麻患者术中低体温中的应用效果。方法:将2021年7月1日~10月31日拟行全麻腹部手术的300例成年患者随机分为G1常规保温组和G2 Bundles保温组各150例,G1常规保温组术中实施常规保温方式,G2 Bundles保温组实施基于循证干预措施和可能引发热量损失途径制订预防术中低温的Bundles干预策略。比较两组不同时间的体温、血氧饱和度(SpO_(2))、心率、血压、呼吸,统计两组寒战、低体温、躁动、术中出血、异常心律事件发生率,记录气管导管拔管时间、PACU停留时间。结果:G2 Bundles保温组术中及术后体温、SpO_(2)、心率、呼吸等均高于G1常规保温组,而同期血压低于G1常规保温组(P<0.05);G2 Bundles保温组寒战、低体温、躁动、术中出血事件、异常心律事件发生率均低于G1常规保温组(P<0.05);G2 Bundles保温组气管导管拔管时间、PACU停留时间均短于G1常规保温组(P<0.01)。结论:将Bundles策略应用于全麻患者术中,有助于预防低体温、调节患者心电指标,减少不良事件。

A Self-calibration Bundle Adjustment Algorithm Based on Block Matrix Cholesky Decomposition Technology

In this study,the problem of bundle adjustment was revisited,and a novel algorithm based on block matrix Cholesky decomposition was proposed to solve the thorny problem of self-calibration bundle adjustment.The innovation points are reflected in the following aspects:①The proposed algorithm is not dependent on the Schur complement,and the calculation process is simple and clear;②The complexities of time and space tend to O(n)in the context of world point number is far greater than that of images and cameras,so the calculation magnitude and memory consumption can be reduced significantly;③The proposed algorithm can carry out self-calibration bundle adjustment in single-camera,multi-camera,and variable-camera modes;④Some measures are employed to improve the optimization effects.Experimental tests showed that the proposed algorithm has the ability to achieve state-of-the-art performance in accuracy and robustness,and it has a strong adaptability as well,because the optimized results are accurate and robust even if the initial values have large deviations from the truth.This study could provide theoretical guidance and technical support for the image-based positioning and 3D reconstruction in the fields of photogrammetry,computer vision and robotics.

Enhancing the awakening to family engagement bundle with music therapy

Survivors of prolonged intensive care unit(ICU)admissions may present undesirable long-term outcomes.In particular,physical impairment and cognitive dysfunction have both been described in patients surviving episodes requiring mechanical ventilation and sedation.One of the strategies to prevent the aforementioned outcomes involves the implementation of a bundle composed by:(1)Spontaneous awakening trial;(2)Spontaneous breathing trial;(3)Choosing proper sedation strategies;(4)Delirium detection and management;(5)Early ICU mobility;and(6)Family engagement(ABCDEF bundle).The components of this bundle contribute in shortening length of stay on mechanical ventilation and reducing incidence of delirium.Since the first description of the ABCDEF bundle,other relevant therapeutic factors have been proposed,such as introducing music therapy.This mini-review describes the current evidence supporting the use of the ABCDEF bundle,as well as current knowledge on the implementation of music therapy.

Characterization of retinal ganglion cell damage at single axon bundle level in mice by visible-light optical coherence tomography fibergraphy

Retinal ganglion cells(RGCs)receive synaptic inputs through their dendritic trees in the inner plexiform layer(IPL)and convey the visual information via their axons which form the optic nerve to the brain(Sanes and Masland,2015).In glaucoma,RGCs and their axons degenerate and die,leading to irreversible vision loss and eventually blindness if left untreated(Quigley,2016).