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.

Exercise-induced left bundle branch block: an infrequent phenomenon: Report of two cases

Exercise-induced left bundle branch block(EI-LBBB)is infrequent phenomenon.We present two patients with angina pectoris who developed EI-LBBB during exercise tolerance test.The first patient with typical angina pectoris had significant obstructive coronary artery disease(CAD)requiring percutaneous coronary intervention of multiple lesions including placement of drug eluting stents.The second patient had atypical chest pain without signs of CAD at all.EI-LBBB occurred at a heart rate of 80 bpm and 141 bpm in the first and second patient,respectively.EI-LBBB remained visible through the test till the recovery period in the first patient at a heart rate of 83 bpm and disappeared at 96bpm in the second patient.Both patients with this infrequent phenomenon are discussed and the literature is reviewed.

Differential diagnosis of tachycardia with a typical left bundle branch block morphology

The evaluation of wide QRS complex tachycardias (WCT)remains a common dilemma for clinicians.Numerous algorithms exist to aid in arriving at the correct diagnosis.Unfortunately,these algorithms are difficult to remember,and overreliance on them may prevent cardiologists from understanding the mechanisms underlying these arrhythmias.One distinct subcategory of WCTs are those that present with a"typical"or"classic" left bundle branch block pattern.These tachycardias may be supraventricular or ventricular in origin and arise from functional or fixed aberrancy,bystander or participating atriofascicular pre-excitation,and bundle branch reentry.This review will describe these arrhythmias,illustrate their mechanisms,and discuss their clinical features and treatment strategies.

Cardiac resynchronization therapy for heart failure induced by left bundle branch block after transcatheter closure of ventricular septal defect

A 54-year-old female patient with congenital heart disease had a persistent complete left bundle branch block three months after closure by an Amplatzer ventricular septal defect occluder. Nine months later, the patient suffered from chest distress, palpitation, and sweating at daily activities, and her 6-min walk distance decreased significantly （155 m）. Her echocardiography showed increased left ventricular end-diastolic diameter with left ventricular ejection fraction of 37%. Her symptoms reduced significantly one week after received cardiac resynchronization therapy. She had no symptoms at daily activities, and her echo showed left ventricular ejection fraction of 46%and 53%. Moreover, left ventricular end-diastolic diameter decreased 6 and 10 months after cardiac resynchronization therapy, and 6-min walk dis-tance remarkably increased. This case demonstrated that persistent complete left bundle branch block for nine months after transcatheter closure with ventricular septal defect Amplatzer occluder could lead to left ventricular enlargement and a significant decrease in left ventricular systolic function. Cardiac resynchronization therapy decreased left ventricular end-diastolic diameter and increased left ventricular ejection fraction, thereby improving the patient’s heart functions.

Delayed spontaneous reversibility of left bundle branch block in non-ischemic cardiomyopathy: a case report

Left bundle branch block(LBBB)causes a delay in left ventricular contraction with an unsynchronized ventricular systole.LBBB is an independent determinant of morbi-mortality mainly when associated with cardiomyopathy and left ventricular dysfunction.[1] LBBB due to non-ischemic cardiomyopathy is considered non-reversible.Such irreversibility occurs because LBBB and cardiomyopathy act in a synergic manner in order to maintain both situations.However,there are a few reports in the literature showing that some patients have had an improvement in cardiac function with normalization of QRS and have experienced a reverse remodelling with pharmacological therapy only.[2–4]

Cardiovascular Risk in Young Workers with Left Bundle Branch Block

Aims: Left bundle branch block (LBBB) is generally associated with a poorer prognosis in comparison to normal intraventricular conduction, but also in comparison to right bundle branch block which is generally considered to be benign in the absence of an underlying cardiac disorder like congenital heart disease. In this paper we evaluate the presence of possible cardiovascular pathology in a group of nurses with a low level of cardiovascular risk factors and left bundle branch block (LBBB). Methods: During the period 2009-2013, 356 nurses (mean age: 32.6 ± 11 yr) were admitted to the department of Occupational Medicine of Second University of Naples. Of these, 13 had LBBB. The evaluation of these patients has included an electrocardiogram (ECG), echocardiography, 24-h ambulatory Holter monitoring (ECG Holter), and exercise testing. Subsequently, in patients with LBBB, multislice computed coronary angiography (MSCT) has been considered. Results and Conclusion: Only in one patient we found a significant stenosis in the middle tract of left anterior descending artery. Coronary artery disease remains difficult to diagnose in some ECG findings such as acquired LBBB. For this reason, a preventive diagnose with newly developed diagnostic methods such as the multislice computed coronary angiography (MSCT) must try to account by the clinician in order to ruling out coronary artery disease (CAD) in workers with LBBB and low cardiovascular risk.

Acute myocardial infarction associated with right bundle branch block and changeable trifascicular block: a case report

Rationale:Acute myocardial infarction in the presence of right bundle branch block.Patient concerns:A 70-year-old,male heavy smoker presented with angina and hypertension.Interventions:Electrocardiography,intravenous nitroglycerin infusion,intravenous streptokinase infusion.Diagnosis:Acute myocardial infarction in the presence of with changeable trifascicular heart block.Outcomes:Dramatic clinical improvement with electrocardiographic ST-segment (whether elevation or reciprocal ST-depression) resolution.Lessons:Acute myocardial infarction may be associated right bundle branch block.Accompanied trifascicular heart block had pre-streptokinase left anterior fascicular block with left axis deviation and post-streptokinase left posterior fascicular block with right axis deviation.

Clinical Profile of the Patients with Newly Detected Left Bundle Branch Block in the Outpatient Department

Objective: The purpose of this study was to evaluate cardiac features associated with newly detected left bundle branch block (LBBB) in the outpatient department. Methods: A total of 57 patients with LBBB pattern were evaluated using electrocardiography (ECG). Patients were assessed based on their sex, age, detailed history, and cardiovascular symptoms. Cardiac investigations including ECG and echocardiography were performed. Results:The study included 30 (52.6%) males and 27 (47.5%) females, aged between 35 and 80 years. Dyspnoea (35.1%) and chest pain (22.8%) were the most common symptoms. 54.4% were hypertensive and 17.5% were diabetics. 28% had Left ventricular systolic dysfunction, and 24.5% had aortic valve disease. Left ventricular hypertrophy without any other structural heart disease was present in 28% of the patients. Only 24.5% patients presented with LBBB had a structurally normal heart in echocardiography. Myocardial performance index in echocardiography was abnormal in LBBB irrespective of the presence of structural heart disease. Conclusion: The prevalence of LBBB was found to increase with age and had slight male preponderance. Dyspnoea on effort was the most common presenting complaint, followed by chest pain and incidental detection of ECG abnormality. Most of the patients were hypertensive. Only 24.5% patients with LBBB had a structurally normal heart. MPI was abnormally high in the presence of LBBB despite having a normal left ventricular ejection fraction.

Left bundle branch block and myocardial infarction, a diagnosis not always easy: Our experience and review of literature

The occurrence of left bundle branch block (LBBB) is quite common in clinical practice. The changes in cardiac repolarization, caused by this disorder of electric conduction, may mask the presence of an acute myocardial infarction (AMI), delaying the diagnostic-therapeutic iter, with an important impact on prognosis. We describe the case of a woman of 59 years with LBBB, came to our observation for a constrictive chest pain associated with dyspnea. The diagnostic workup for suspected acute coronary syndrome (ACS), initially conducted only on the analysis of the electrocardiogram (negative TnI at entry), showed the presence of coronary arteries free of stenosis. However, the diagnostic confirmation of AMI was completed after the rise of cardiac markers and the electrocardiographic changes. This case confirm the difficulty about the diagnosis of AMI in patients with LBBB and stresses, however, as the use of some criteria proposed in the literature [1-3] can guide to its identification, directing patient to an appropriate treatment.

Prognostic implication of the coronary microvascular dysfunction in patients with isolated left bundle branch block

The present study aims to determine the influence of microvascular dysfunction (MVD) in the prognosis of patients presenting isolated left bundle branch block (LBBB). Methods: We studied 30 patients (pts), 22 males, 8 females, mean age 57 ± 4 years, with isolated LBBB, with a mean follow up of 48 ± 6 months. The control group consisted of 20 healthy individuals, 12 males, mean age 52 ± 10 years. Both groups were screened for cardiovascular risk factors (RF);they also had an echocardiogram and Coronary CT Scan, ruling out both structural heart disease and obstructive lesions of the epicardial coronary arteries. A myocardial perfusion study was then performed, with two groups emerging according to these results: Group A, 8 pts (26%), with reversible perfusion defects, in which the diagnosis of MVD was suspected, and Group B, 22 pts (74%), with either normal perfusion or minor septal/apical reversible defects (related to LBBB). All Group A pts, and 9 of the Group B pts, underwent coronary arteriography, with intracoronary acetylcholine and nitroglycerine infusion, thus evaluating vasomotor response as endothelium dependent (acetylcholine) or endothelium independent (nitroglycerine). During follow up, we reviewed functional class, 12 lead ECG and echocardiogram on a yearly basis. Results: All Group A patients had an abnormal acetylcholine response;only three of them had abnormal response to nitroglycerine infusion, suggesting endothelium dependent MVD. Of those in Group B, only one patient had abnormal acetylcholine response. At the end of the follow up period, 3 pts (37%) in Group A, showed functional class decrease vs 5 pts (22%) of those in Group B. In Group A, a significant increase of End Diastolic Left Ventricle Diameter (EDLVD) was found (51.6 ± 3.6 vs 59.3 ± 6.8 mm;p < 0.05) with significant decrease in LVEF (62 ± 4.8 vs 46% ± 3.7%, p variation. In neither group major complications (death, heart failure admissions) were found. Conclusion: We confirm the association between MVD and a worse clinical prognosis in isolated LBBB patients. Repeated ischemia and myocardial fibrosis are highlighted as possible physiopathological mechanisms, precluding a progressive left ventricular function decrease, with a higher mortality and arrhythmia risk. Endothelial function preserving strategies, both preventive and therapeutic, might be useful in improving LBBB with MVD patient’s prognosis.

Association between Magnetic Resonance Imaging and the Result of Medial Branch Blocks

The aim of this retrospective practice audit was to assess the correlation between painful zygapophysial joints and changes seen in magnetic resonance imaging (MRI). Patients with unilateral pain were tested with controlled medial branch blocks. The MRI scans of patients with a positive response were compared blinded with normal MRI scans. The dimensions of the joint were assessed and osteoarthritis was graded. Fifteen symptomatic patients and 15 asymptomatic patients were included and evaluated. Comparison of the joints showed that the maximum diameter of symptomatic joints was significantly larger, and the grading of osteoarthritis was significantly higher for symptomatic joints. No healthy patient was assigned a grade 3. Grades 2 and 3 were found significantly more often in symptomatic patients. Only one symptomatic joint was assigned grade 0. Grade 0 was found significantly more often in asympto-matic patients. The presented MRI technique has limited value as a diagnostic test for lumbar zygapophysial joint pain. It is not possible to detect a single symptomatic joint. However, the osteoarthritis grading for the lumbar zyg-apophysial joints might be helpful for finding predictors for negative response if the results of the rating are grade zero. Therefore, unnecessary medial branch blocks might be avoided.

Can regadenoson pharmacologic SPECT be performed effectively in patients with left bundle branch block or paced rhythm patients? A retrospective comparison to adenosine SPECT

Purpose: Regadenoson (REG) is currently becoming the stress agent of choice in patients undergoing pharmacologic single photon emission computed tomography (SPECT). However, in patients with left bundle branch block (LBBB) and ventricular paced rhythm (VPR), hesitation exists amongst clinicians to use REG-SPECT due to the concern that the increased heart rate could cause false positive SPECT results. We sought to evaluate the comparability of A-SPECT and REG-SPECT in patients with LBBB and VPR. Methods: Retrospective study of 30 patients who served as their own controls. All 30 patients who underwent REG-SPECT (Grp 1) were compared to their prior A-SPECT (Grp 2) done within two years prior to REG-SPECT. Heart rate (HR) and blood pressure (BP) parameters, ECG, stress perfusion and gated variables, SPECT ischemia, and side-effects were evaluated. Statistical significance was set at P < 0.05. Results: Grp 1 and Grp 2 were comparable in hemodynamic parameters with increase in HR and decrease in systolic and diastolic BP with administration of adenosine and REG stress agents. However, there were no significant differences found in hemodynamic parameters and II degree AV block between the groups. All normal A-SPECT were found to be normal with REG-SPECT. No differences could be found between the two groups among SPECT parameters. Muscle pain was significantly higher in REG (10.0% vs. 0.0%, P = 0.083) and so was the use of aminophylline (16.7% vs. 0.0%, P = 0.025) to relieve the side-effect. Conclusion: REG-SPECT can be administered in patients with LBBB and VPR patients based on favorable and comparable hemodynamic responses and arrhythmia occurrences to A-SPECT. REG-SPECT can also be used for adequate interpretation of presence or absence of SPECT ischemia particularly in the LAD territory without any concern for false positive perfusion defects.

Block Based Bivariate Blending Rational Interpolation via Symmetric Branched Continued Fractions

This paper constructs a new kind of block based bivariate blending rational interpolation via symmetric branched continued fractions. The construction process may be outlined as follows. The first step is to divide the original set of support points into some subsets (blocks). Then construct each block by using symmetric branched continued fraction. Finally assemble these blocks by Newton’s method to shape the whole interpolation scheme. Our new method offers many flexible bivariate blending rational interpolation schemes which include the classical bivariate Newton’s polynomial interpolation and symmetric branched continued fraction interpolation as its special cases. The block based bivariate blending rational interpolation is in fact a kind of tradeoff between the purely linear interpolation and the purely nonlinear interpolation. Finally, numerical examples are given to show the effectiveness of the proposed method.

Outcomes in patients with COVID-19 and new onset heart blocks: Insight from the National Inpatient Sample database

BACKGROUND Coronavirus disease 2019(COVID-19)caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has resulted in a worldwide health crisis since it first appeared.Numerous studies demonstrated the virus’s predilection to cardiomyocytes;however,the effects that COVID-19 has on the cardiac conduc-tion system still need to be fully understood.AIM To analyze the impact that COVID-19 has on the odds of major cardiovascular complications in patients with new onset heart blocks or bundle branch blocks(BBB).METHODS The 2020 National Inpatient Sample(NIS)database was used to identify patients admitted for COVID-19 pneumonia with and without high-degree atrioven-tricular blocks(HDAVB)and right or left BBB utilizing ICD-10 codes.The patients with pre-existing pacemakers,suggestive of a prior diagnosis of HDAVB or BBB,were excluded from the study.The primary outcome was inpatient mortality.Secondary outcomes included total hospital charges(THC),the length of hospital stay(LOS),and other major cardiac outcomes detailed in the Results section.Univariate and multivariate regression analyses were used to adjust for confounders with Stata version 17.RESULTS A total of 1058815 COVID-19 hospitalizations were identified within the 2020 NIS database,of which 3210(0.4%)and 17365(1.6%)patients were newly diagnosed with HDAVB and BBB,respectively.We observed a significantly higher odds of in-hospital mortality,cardiac arrest,cardiogenic shock,sepsis,arrythmias,and acute kidney injury in the COVID-19 and HDAVB group.There was no statistically significant difference in the odds of cerebral infarction or pulmonary embolism.Encounters with COVID-19 pneumonia and newly diagnosed BBB had a higher odds of arrythmias,acute kidney injury,sepsis,need for mechanical ventilation,and cardiogenic shock than those without BBB.However,unlike HDAVB,COVID-19 pneumonia and BBB had no significant impact on mortality compared to patients without BBB.CONCLUSION In conclusion,there is a significantly higher odds of inpatient mortality,cardiac arrest,cardiogenic shock,sepsis,acute kidney injury,supraventricular tachycardia,ventricular tachycardia,THC,and LOS in patients with COVID-19 pneumonia and HDAVB as compared to patients without HDAVB.Likewise,patients with COVID-19 pneumonia in the BBB group similarly have a higher odds of supraventricular tachycardia,atrial fibrillation,atrial flutter,ventricular tachycardia,acute kidney injury,sepsis,need for mechanical ventilation,and cardiogenic shock as compared to those without BBB.Therefore,it is essential for healthcare providers to be aware of the possible worse predicted outcomes that patients with new-onset HDAVB or BBB may experience following SARS-CoV-2 infection.

腰椎小关节疼痛介入治疗中美专家共识(2024)

慢性腰痛是一类严重影响患者生活质量的常见病症,其中由腰椎小关节紊乱导致的轴性腰痛(简称“腰椎小关节疼痛”)最为常见。介入治疗(诊断性阻滞和射频治疗)是腰椎小关节疼痛最有效且安全的治疗方法,但其临床安全性和技术细节目前仍缺乏明确的指导方针。为此,中美疼痛医学领域多位专家基于最新循证医学证据,共同制定了《腰椎小关节疼痛介入治疗中美专家共识(2024)》,旨在以患者为中心,以优化腰椎小关节疼痛介入治疗为目的,对患者选择、诊断性阻滞和标准射频技术的细节及注意事项及相关并发症提出专业建议,以期更好地指导临床实践。

左束支区域起搏在改善右束支阻滞、射血分数降低患者心功能中的应用效果

目的探究左束支区域起搏(LBBaP)在改善右束支阻滞(RBBB)、射血分数降低(LVEF)≤35%患者心电图及心功能改善的效果。方法选取2020年2月到2022年8月期间九江市第一人民医院心血管内科的80例RBBB且LVEF≤35%患者作为研究对象,采用随机数字表法将其分为对照组(40例)及试验组(40例)。对照组给予双室起搏(Bi-V),试验组给予LBBaP。比较两组患者治疗前后左室舒张末径(LVDED)、左室射血分数(LVEF)、6 min步行距离(6MWD)、NN间期标准差(SDNN)、相邻NN间期之差的均方根值(rMSSD)、每5分钟NN间期均值的标准差(SDANN)、ST-T波改变情况、心力衰竭再入院率、死亡发生率、主要并发症(心脏穿孔、心包积血、恶性心律失常、心源性猝死和急性心肌梗死)。结果两组患者治疗前LVDED、LVEF、6MWD比较,差异无统计学意义(P>0.05)。两组患者治疗后LVDED低于本组治疗前,LVEF高于本组治疗前,6MWD长于本组治疗前,差异有统计学意义(P<0.05)。试验组治疗后低于对照组,LVEF高于对照组,6MWD长于对照组,差异有统计学意义(P<0.05)。试验组的ST-T波改变率高于对照组,SDNN、rMSSD、SDANN均低于对照组,差异有统计学意义(P<0.05)。试验组心力衰竭再入院率、并发症发生率、死亡率均低于对照组,差异有统计学意义(P<0.05)。结论左束支区域起搏可有效改善心功能及心电图指标,降低心力衰竭再入院率、并发症发生率、死亡率,值得推广。

左束支区域起搏对房室传导阻滞患者术后新发房性心律失常的影响

目的探讨左束支区域起搏(left bundle branch area pacing,LBBaP)对房室传导阻滞(AVB)患者术后新发心房颤动(new-onset atrial fibrillation,NOAF)和心房高频事件(atrial high rate episodes,AHREs)的影响。方法回顾性纳入84例行起搏治疗的三度房室传导阻滞(ⅢAVB)患者,根据心室电极位置分为LBBaP组(n=42)和右室间隔部起搏(RVSP)组(n=42)。比较两组患者术前术后QRS波时限(QRSd)、心室起搏参数,并发症、脑卒中事件和NOAF、AHREs发生率。结果(1)LBBaP组术后NOAF、AHREs发生率均低于RVSP组(P<0.05)。(2)LBBaP组的p-QRSd短于RVSP组(P<0.05)。(3)两组患者心室起搏参数、并发症及脑卒中事件发生率之间差异无统计学意义(P>0.05)。结论相对于右室起搏,LBBaP术后AHREs、NOAF的发生率较低,可改善患者预后。

室间隔肌壁间纤维化与左束支传导阻滞的相关性及对新发左束支传导阻滞的预测价值

目的探讨室间隔肌壁间纤维化(SMF)与左束支传导阻滞(LBBB)的相关性,并通过分析新发LBBB的危险因素,评估室间隔肌壁间纤维化对新发LBBB的预测价值。方法回顾性分析2018年1月至2022年1月于河南省人民医院心脏中心/华中阜外医院住院诊疗的所有行心脏磁共振患者的临床资料,根据患者心电图是否存在LBBB,将患者分为LBBB组和非LBBB组。比较两组患者的临床资料,并采用单因素及多因素Logistic回归分析,评估LBBB的相关危险因素。对无LBBB组的患者进行电话随访至出现新发LBBB或2023年10月为止,并采用单因素及多因素Cox回归分析,评估新发LBBB的危险因素。结果与无LBBB患者相比,LBBB患者的年龄更大,左心房直径、左室质量及左室舒张、收缩末期内径和容积均更大,左室射血分数更低,QRS间期持续时间更长,扩张型心肌病、SMF发生率更高,差异均有统计学意义(P<0.05)。多因素Logistic回归分析显示,年龄(OR=1.073;95%CI:1.049~1.097;P<0.001)、左室质量(OR=1.010,95%CI:1.004~1.016;P=0.001)、SMF(OR=2.227,95%CI:1.232~4.028;P=0.008)是LBBB存在的独立相关因素。平均随访(43.4±11.7)月,新发LBBB患者42例,Kaplan-Meier分析显示,存在SMF的患者新发LBBB的比率显著高于无SMF的患者(18.5%vs.6.9%,P<0.001)。在多因素Cox回归分析中,年龄(HR=1.042,95%CI:1.018~1.066,P<0.001)、左室质量(HR=1.012,95%CI:1.005~1.020,P=0.001)和SMF(HR=3.320,95%CI:1.768~6.232,P<0.001)是新发LBBB的独立预测因素。结论SMF与LBBB存在相关性且是新发LBBB的独立预测因素。心脏磁共振显示存在SMF的患者有较高的风险出现LBBB,需重点关注。

基于逆阻型IGCT器件的固态式直流断路器设计及研制

直流系统是支撑高比例新能源接入与灵活高效用能的重要技术方向。固态式直流断路器(solid state DC circuit breaker,SSCB)具有开断速度极快、无电弧、寿命长等优点,在中低压直流系统的故障保护中得到广泛应用。随着电力电子器件的发展,固态式直流断路器的拓扑结构、工作性能也在不断进步。为此基于逆阻型集成门极换流晶闸管(intergated gate commutate thyristor,IGCT),提出了一种新型的固态式直流断路器结构及设计方法,通流支路采用逆阻IGCT反并联结构实现双向通流,缓冲支路采用金属氧化物避雷器(metal oxide varistor,MOV)-电容结构来抑制过电压,吸能支路采用MOV吸收系统能量。进一步地,给出了关键元器件的参数设计方法,并验证了有效性;设计了性能良好的重力热管散热器,单个模块散热功率可达700 W;提出了主被动结合的控保策略,提高断路器的保护性能。最后,研制了固态式直流断路器样机,可用于750 V以内的低压直流系统,额定通流可达2 kA,可在百微秒内开断10 kA故障电流,成本低、体积小、高可靠,具有良好的应用前景。

基于双分支边缘卷积融合网络的红外与可见光图像融合方法

提出一种基于双分支边缘卷积融合网络的红外与可见光图像融合方法。首先,提出一种改进的双分支边缘卷积结构,将图像包含的信息分解为公共信息和模态信息,并于每个分支引入边缘卷积块,更好的提取深度特征;然后在融合层引入卷积注意力模块对模态特征进行增强;最后基于所本文编解码网络特点,提出一种重建损失结合融合损失的损失函数。经过大量的消融性实验和对比实验表明,本文方法能够很好的保留原图像中的公共信息和模态信息,并且相比目前最新的融合方法在主观和客观评价上都具有优秀的综合性能。