Wireless Power Supply Based on MNG-MNZ Metamaterial for Cardiac Pacemakers

To solve the low power transfer efficiency and magnetic field leakage problems of cardiac pacemaker wireless powering, we proposed a wireless power supply system suitable for implanted cardiac pacemaker based on mu-negative(MNG) and mu-nearzero(MNZ) metamaterials. First, a hybrid metamaterial consisted of central MNG unit for magnetic field concentration and surrounding MNZ units for magnetic leakage shielding was established by theoretical calculation. Afterwards, the magnetic field distribution of wireless power supply system with MNG-MNZ metamaterial slab was acquired via finite element simulation and verified to be better than the distribution with conventional MNG slab deployed. Finally, an experimental platform of wireless power supply system was established with which power transfer experiment and system temperature rise experiment were conducted.Simulation and experimental results showed that the power transfer efficiency was improved from 44.44%,19.42%, 8.63% and 6.19% to 55.77%, 62.39%, 20.81%and 14.52% at 9.6 mm, 20 mm, 30 mm and 50 mm,respectively. The maximum SAR acquired by SAR simulation under human body environment was-7.14 dbm and maximum reduction of the magnetic field strength around the receiving coil was 2.82 A/m. The maximum temperature rise during 30min charging test was 3.85℃,and the safety requirements of human bodies were met.

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.

Risk of permanent pacemaker implantation following transcatheter aortic valve replacement:Which factors are most relevant?

Transcatheter aortic valve replacement(TAVR)has emerged as a formidable treatment option for severe symptomatic aortic stenosis ahead of surgical aortic valve replacement.The encouraging results from large randomized controlled trials has resulted in an exponential rise in the use of TAVR even in the low-risk patients.However,this is not without challenges.Need for permanent pacemaker(PPM)post-TAVR remains the most frequent and clinically relevant challenge.Naturally,identifying risk factors which predispose an individual to develop high grade conduction block post-TAVR is important.Various demographic factors,electrocardiographic features,anatomic factors and procedural characteristics have all been linked to the development of advanced conduction block and need for PPM following TAVR.Amongst these electrophysiological variables,most notably a prolonged QRS>120 ms regardless of the type of conduction block seems to be one of the strongest predictors on logistic regression models.The index study by Nwaedozie et al highlights that patients requiring PPM post-TAVR had higher odds of having a baseline QRS>120 ms and were more likely to be having diabetes mellitus that those who did not require PPM.

Current knowledge for the risk factors of early permanent pacemaker implantation following transcatheter aortic valve replacement and what is next for the primary prevention?

In this editorial,we comprehensively summarized the preoperative risk factors of early permanent pacemaker implantation after transcatheter aortic valve replacement(TAVR)among patients with severe aortic stenosis from several renowned clinical studies and focused on the primary prevention of managing the modifiable factors,e.g.,paroxysmal atrial fibrillation before the TAVR.

Transcatheter aortic valve replacement in low-risk young population:A double edge sword?

Since the advent of transcatheter aortic valve replacement(TAVR)in 2002,it has now become the default interventional strategy for symptomatic patients presenting with severe aortic stenosis,particularly in intermediate to highsurgical risk patients.In 2019,the United States Food and Drug Administration approved TAVR in low-risk patients based on two randomized trials.However,these breakthrough trials excluded patients with certain unfavorable anatomies and odd profiles.While currently there is no randomized study of TAVR in young patients,it may be preferred by the young population given the benefits of early discharge,shorter hospital stay,and expedite recovery.Nonetheless,it is important to ruminate various factors including lifetime expectancy,risk of pacemaker implantation,and the need for future valve or coronary interventions in young cohorts before considering TAVR in these patients.Furthermore,the data on long-term durability(>10 years)of TAVR is still unknown given most of the procedures were initially performed in the high or prohibitive surgical risk population.Thus,this editorial aims to highlight the importance of considering an individualized approach in young patients with consideration of various factors including lifetime expectancy while choosing TAVR against surgical aortic valve replacement.

Misinterpretation of sleep-induced second-degree atrioventricular block

A number of publications have claimed that Mobitz type Ⅱ atrioventricular block(AVB)may occur during sleep.None of the reports defined type Ⅱ AVB and representative electrocardiograms were either misinterpreted or missing.Relatively benign Wenckebach type Ⅰ AVB is often misdiagnosed as Mobitz type Ⅱ which is an indication for a pacemaker.Review of the published reports indicates that Mobitz type II AVB does not occur during sleep when it is absent in the awake state.Conclusion:There is no proof that sleep is associated with Mobitz type Ⅱ AVB.

Pacemaker post transcatheter aortic valve replacement:A multifactorial risk?

Pacemaker post-transcatheter aortic valve replacement is related to multifactorial risk.Nwaedozie et al brought to the body of evidence electrocardiogram and clinical findings.However,procedural characteristics have at least as much impact on the final need for a permanent pacemaker and potentially on the pacing rate.In this regard,long-term follow-up and understanding of the impact of long-term stimulation is of utmost importance.

The Peripheral Hospital as Focal Point for Pacemaker Activity: Review of the Last 300 Implantations Carried out at the Haute Correze Hospital Center

Background: Pacemaker implantation is a very old activity which has revolutionized the cardiology practice throughout the world. This activity is effective at the Haute Correze Hospital Center since more than 20 years. Due to progress in this area, and the increasing request within this center located at the outskirts of town, we set out to evaluate our pacemaker activity in general and more specifically to assess the post-procedural complications in our series patients. Methodology: This was a retrospective longitudinal study. Data were recorded for period of 90 months from 27/05/2016 to 19/11/2023. This data collection was possible via a specific register completed by computerized patient data from the SillageTM software. All files of patients implanted with single or dual chamber pacemakers were included, generator replacements, upgrading procedures and addition of leads were excluded. The sampling was non-probabilistic, consecutive and non-exhaustive. Statistical analysis was carried out using the Excel 2019 spreadsheet and SPSS version 23 software. The quantitative variables were presented as mean ± standard deviation, the qualitative data as proportions. Results: A total of 303 first-time pacemaker’s implantations were carried out during the study period (rate of 40 per year). The average age in the population was 79.7 ± 9.4 years (44 - 99 years) with a male predominance of 63.7% (n = 193). Atrioventricular block (2nd and 3rd degree) was the main indication for pacemaker implantation in 42.9% of cases (n = 130). Patients were most often implanted with a dual-chamber pacemaker (57.7%, n = 175). The approach was most often cephalic in 72.6% of cases (n = 220), followed by the subclavian access in 27.4% of cases (n = 84). The average fluoroscopy time was 7.9 min ± 2.4 (1 - 43). The average irradiation dose in gray/cm2 was 12.4 ± 9.3 (0.22 - 117.5). The average length of hospitalization was 7 ± 4 (2 - 26) days. The overall complication rate at one year was 12.9% (n = 39). These complications are distributed as follows: Leads dislodgement in 8.2% (n = 25), hematoma 3.6% (n = 11) all without clinical consequences, pneumothorax 0.7% (n = 2), both cases of pneumothorax did not require specific care, infection (superficial) in 0.3% (n = 1). Leads dislodgement occurred after a median time of 18 days (IQR: 3 - 36). The earliest dislodgement was observed on D0 and the latest on D207. No serious complications were recorded. The average atrial threshold at implantation/first control/last follow-up was 0.7/1.3/0.8 V, respectively. The average ventricular threshold at implantation/first control/last follow-up was 0.5/1.08/0.87 V, respectively. The average atrial detection at implantation/first control/last follow-up was 3.2/2.3/ 2.05 mv, respectively. The average ventricular detection at implantation/first control/last follow-up was 10.3/11.03/10.8 mv. The average atrial impedance at implantation/first control/last follow-up was 610/457/457 ohms. The average ventricular impedance at implantation/first control/last follow-up was 754/547/563 ohms. Conclusion: Pacemaker implantation is safe at the Haute Correze Hospital Center with a relatively low rate of complications, in this case an almost zero major infection and no serious hematoma. The peripheral hospital should remain a focal point of this activity in order to respond more quickly to the needs of the populations.

Application Effect of External Diaphragm Pacemaker Combined with Active Respiratory Circulation Technology in Pulmonary Rehabilitation of Perioperative Lung Cancer Patients

Aim: To explore the application effect of external diaphragm pacemaker combined with active respiratory circulation technology in pulmonary rehabilitation of perioperative lung cancer patients. Methods: A total of 98 lung cancer patients admitted to our hospital from April 2020 to November 2021 were selected as the observation objects, and then divided into a control group and an observation group using the random number table method, with 49 cases in each group. The control group received routine admission guidance and active respiratory circulation training, while the observation group was supplemented with external diaphragm pacemaker on the basis of the control group. The intervention effect was evaluated by blood gas indicators, pulmonary function indicators, diaphragm function indicators, sputum comfort degree, and activity tolerance indicators before and after intervention. Results: Before intervention, there were no significant differences in blood gas analysis indicators, pulmonary function indicators, diaphragm function indicators, sputum comfort degree, and activity tolerance indicators between the two groups (P > 0.05). After intervention, the improvement degree of the above indicators in the observation group was higher than that in the control group (P < 0.05). Conclusions: The application of external diaphragm pacemaker combined with active respiratory circulation technology in pulmonary rehabilitation of perioperative lung cancer patients is significant, which can effectively improve the pulmonary function, blood gas function, and diaphragm function of lung cancer patients after surgery, and improve the activities of daily living and quality of life of patients.

Prediction of permanent pacemaker implantation after transcatheter aortic valve replacement:The role of machine learning

BACKGROUND Atrioventricular block requiring permanent pacemaker(PPM)implantation is an important complication of transcatheter aortic valve replacement(TAVR).Application of machine learning could potentially be used to predict preprocedural risk for PPM.AIM To apply machine learning to be used to predict pre-procedural risk for PPM.METHODS A retrospective study of 1200 patients who underwent TAVR(January 2014-December 2017)was performed.964 patients without prior PPM were included for a 30-d analysis and 657 patients without PPM requirement through 30 d were included for a 1-year analysis.After the exclusion of variables with near-zero variance or≥50%missing data,167 variables were included in the random forest gradient boosting algorithm(GBM)optimized using 5-fold cross-validations repeated 10 times.The receiver operator curve(ROC)for the GBM model and PPM risk score models were calculated to predict the risk of PPM at 30 d and 1 year.RESULTS Of 964 patients included in the 30-d analysis without prior PPM,19.6%required PPM post-TAVR.The mean age of patients was 80.9±8.7 years.42.1%were female.Of 657 patients included in the 1-year analysis,the mean age of the patients was 80.7±8.2.Of those,42.6%of patients were female and 26.7%required PPM at 1-year post-TAVR.The area under ROC to predict 30-d and 1-year risk of PPM for the GBM model(0.66 and 0.72)was superior to that of the PPM risk score(0.55 and 0.54)with a P value<0.001.CONCLUSION The GBM model has good discrimination and calibration in identifying patients at high risk of PPM post-TAVR.

Upper extremity deep vein thrombosis:An intensivist’s perspective

Upper extremity deep vein thrombosis(UEDVT)is less common than lower extremity DVT but is a cause of significant morbidity and mortality in intensive care unit patients.Increasing cancer incidence,prolonged life expectancy and increasing use of intravascular catheters and devices has led to an increased incidence of UEDVT.It is also associated with high rates of complications like pulmonary embolism,post-thrombotic syndrome and recurrent thrombosis.Clinical prediction scores and D-dimer may not be as useful in identifying UEDVT;hence,a high suspicion index is required for diagnosis.Doppler ultrasound is commonly employed for diagnosis,but other tests like computed tomography and magnetic resonance imaging venography may also be required in some patients.Contrast venography is rarely used in patients with clinical and ultrasound findings discrepancies.Anticoagulant therapy alone is sufficient in most patients,and thrombolysis and surgical decompression is seldom indicated.The outcome depends on the cause and underlying comorbidities.

Bow-and-arrow sign on point-of-care ultrasound for diagnosis of pacemaker lead-induced heart perforation:A case report and literature review

BACKGROUND Pacemaker lead-induced heart perforation is a rare but life-threatening complication of pacemaker implantation,and timely diagnosis remains a challenge for clinicians.Here,we report a case of pacemaker lead-induced cardiac perforation rapidly diagnosed by a“bow-and-arrow”sign on point-of-care ultrasound(POCUS).CASE SUMMARY A 74-year-old Chinese woman who had undergone permanent pacemaker implantation 26 d before suddenly developed severe dyspnea,chest pain,and hypotension.The patient had received emergency laparotomy for an incarcerated groin hernia and was transferred to the intensive care unit 6 d before.Computed tomography was not available due to unstable hemodynamic status,so POCUS was performed at the bedside and revealed severe pericardial effusion and cardiac tamponade.Subsequent pericardiocentesis yielded a large volume of bloody pericardial fluid.Further POCUS by an ultrasonographist revealed a unique“bow-and-arrow”sign indicating right ventricular(RV)apex perforation by the pacemaker lead,which facilitated the rapid diagnosis of lead perforation.Given the persistent drainage of pericardial bleeding,urgent off-pump open chest surgery was performed to repair the perforation.However,the patient died of shock and multiple organ dysfunction syndrome within 24 h post-surgery.In addition,we also performed a literature review on the sonographic features of RV apex perforation by lead.CONCLUSION POCUS enables the early diagnosis of pacemaker lead perforation at the bedside.A step-wise ultrasonographic approach and the“bow-and-arrow”sign on POCUS are helpful for rapid diagnosis of lead perforation.

Hyperthyroidism and severe bradycardia:Report of three cases and review of the literature

BACKGROUND Hyperthyroidism often leads to tachycardia,but there are also sporadic reports of hyperthyroidism with severe bradycardia,such as sick sinus syndrome(SSS)and atrioventricular block.These disorders are a challenge for clinicians.CASE SUMMARY We describe three cases of hyperthyroidism with SSS and found 31 similar cases in a PubMed literature search.Through the analysis of these 34 cases,we found 21 cases of atrioventricular block and 13 cases of SSS,with 67.6%of the patients experiencing bradycardia symptoms.After drug treatment,temporary pacemaker implantation,or anti-hyperthyroidism treatment,the bradycardia of 27 patients(79.4%)was relieved,and the median recovery time was 5.5(2-8)d.Only 7 cases(20.6%)needed permanent pacemaker implantation.CONCLUSION Patients with hyperthyroidism should be aware of the risk of severe bradycardia.In most cases,drug treatment or temporary pacemaker placement is recommended for initial treatment.If the bradycardia does not improve after 1 wk,a permanent pacemaker should be implanted.

Perioperative coagulation activation after permanent pacemaker placement

BACKGROUND Bradyarrhythmias are typically treated with permanent pacemakers(PM). The elimination of bradyarrhythmia by PM implantation improves the patient’s quality of life and prognosis, but it can also result in a number of sequalae. It is still unclear how PM implantation affects the hemostasis system’s parameters and how such parameters relate to different consequences after PM placement.AIM To assess the blood coagulation factor activity in PM patients throughout the perioperative period.METHODS Patients treated in the Department of Surgical Therapy of Cardiac Arrhythmias and Pacing at the Ryazan State "Regional Clinical Cardiology Dispensary" from April 2020 to December 2021 were included in the study. Before surgery, 7 and 30 d after PM placement, peripheral venous blood samples were withdrawn to measure the level of blood coagulation factor Ⅰ(FⅠ) and the activity of blood coagulation factors Ⅱ(FⅡ), Ⅴ(FⅤ), Ⅶ(FⅦ), Ⅷ(FⅧ), ⅸ(Fⅸ), ⅹ(Fⅹ), Ⅺ(FⅪ), Ⅻ(FⅫ). We used an automatic coagulometer Sysmex CA 660(Sysmex Europe, Germany) and reagents from Siemens(Siemens Healthcare Diagnostics Products GmbH, Germany).RESULTS The study included 146 patients. The activity of factors FⅤ [147.7(102.1-247.55)% vs 103.85(60-161.6)% vs 81.8(67.15-130.65)%, P = 0.002], FⅧ [80.4(60.15-106.25)% vs 70.3(48.5-89.1)% vs 63.7(41.6-88.25)%, P = 0.039], Fⅸ [86.2(70.75-102.95)% vs 75.4(59.2-88.3)% vs 73.9(56.45-93.05)%, P = 0.014], Fⅹ [188.9(99.3-308.18)% vs 158.9(83.3-230)% vs 127.2(95.25-209.35)%, P = 0.022], FⅪ [82.6(63.9-103.6)% vs 69.75(53.8-97.6)% vs 67.3(54.25-98.05)%, P = 0.002], FⅫ [87.6(67.15-102.3)% vs 78.9(63.4-97.05)% vs 81.2(62.15-97.4)%, P < 0.001] decreased at 7 and 30 d after surgery;FⅡ activity [157.9(109.7-245.25)% vs 130(86.8-192.5)% vs 144.8(103.31-185.6)%, P = 0.021] decreased at 7 d and increased at 30 d postoperatively. There were no statistically significant changes in the FVII activity within 30 d after PM placement [182.2(85.1-344.8)% vs 157.2(99.1-259)% vs 108.9(74.9-219.8)%, P = 0.128]. Subgroup analysis revealed similar changes only in patients on anticoagulant therapy. FⅫ activity decreased in patients on antiplatelet therapy [82(65.8-101.9)% vs 79.9(63.3-97.1)% vs 89.7(75.7-102.5)%, P = 0.01] 7 d after surgery, returning to baseline values at 30 d postoperatively.CONCLUSION PM placement and anticoagulant therapy were associated with decreased activity of clotting factors FⅤ, FⅧ, Fⅸ, Fⅹ, FⅪ, FⅫ in the postoperative period. FⅧ activity did not decrease within 30 d after PM placement, which may indicate endothelial injury caused by lead placement.

Balloon venoplasty for disdialysis syndrome due to pacemakerrelated superior vena cava syndrome with chylothorax postbacteraemia: A case report

BACKGROUND Although superior vena cava(SVC)syndrome has also been reported as a late complication of pacemaker(PM)implantation,acute onset of SVC syndrome caused by disdialysis syndrome in patients with PM implantation is very rare.There are no specific therapies or guidelines.CASE SUMMARY A 96-year-old woman receiving dialysis was implanted with a PM due to sick sinus syndrome.She was referred to our facility for chest discomfort experienced during dialysis.Upon examination,unilateral pleural effusion on the right side was cloudy with a foul odour.The patient was diagnosed with pyothorax and treated with antibiotics.After the effusion was reduced,it gradually reaggravated and remained cloudy.In this case,SVC syndrome,which is generally considered a late complication after PM implantation,rapidly developed following the bacteraemia,resulting in impaired venous return,chylothorax,and disdialysis syndrome.After catheter intervention for SVC stenosis,the patient’s symptoms promptly improved.The patient has been recurrence-free for a year.CONCLUSION Acute SVC syndrome can cause dysdialysis in PM-implanted patients.Catheter intervention alone has improved this condition for a traceable period.

Successful leadless pacemaker implantation in a patient with dextroversion of the heart:A case report

BACKGROUND Dextroversion is defined as the presence of dextrocardia with situs solitus,dextroloop ventricles,and normally related great arteries.Dextrocardia can pose technical challenges when interventional treatments are required.However,the challenges posed by dextroversion can be amplified due to the disruption of typical anatomical relationships,the unpredictable positioning and boundaries of cardiac structures resulting from the shift,and the pathological processes influencing rotation.CASE SUMMARY A 73-year-old woman with cardiac dextroversion suffered from a recurrence of atrial fibrillation after her radiofrequency catheter ablation and Despite the cessation of antiarrhythmic medications,there were episodes of sinus pauses and symptomatic bradycardia,with heart rates dropping as low as 28 beats per minute.CONCLUSION Dextroversion makes the implantation of leadless pacemakers more challenging,and appropriate adjustments in fluoroscope angles may be crucial for intracardiac operations.Additionally,when advancing delivery systems,attention should be paid to rotational direction during valve-crossing procedures;changes in the perspective of posture angle between normal cardiac position and dextroversion can serve as references.

Lead helix winding tricuspid chordae tendineae: A case report

BACKGROUND As left bundle branch pacing(LBBP)is more like physiological pacing,LBBP has emerged as a novel pacing strategy that uses the native conduction system to improve ventricular synchronization with stable pacing parameters.LBBP has been revealed associated with a significantly reduced risk of new-onset atrial fibrillation and heart failure compared with conventional permanent pacemaker implantation.CASE SUMMARY A 64-year-old man was admitted with a 24-h history of chest distress and shortness of breath,which continued unabated.The patient had no symptoms of chest pain,dizziness,syncope,nausea nor vomiting.There were no abnormalities found in routine examinations after admission.Twelve-lead electrocardiogram presented a result of 2:1 atrioventricular block.Coronary angiography was performed the next day and no abnormality was found.Finally,the patient agreed to received LBBP and signed the informed consent.During the process of withdrawing the Medtronic Model 3830 lead into sheath,we found the lead helix was wrapped around the chordae tendineae of the septal valve of tricuspid.Attempts to rotate the 3830 lead failed to release the lead helix from the chordae tendineae,and ultimately we used radiofrequency ablation to ablate the wrapped chordae tendineae.CONCLUSION Radiofrequency ablation effectively solved this problem without complications.It is an effective and reliable method to resolve lead winding chordae.

Subclavian Arterial Bleeding during Permanent Pacemaker Implantation: Clinical Case Report and Literature Review

Research objective: To study a clinical case that had a complication of subclavian artery bleeding during permanent pacemaker implantation process. Subject and Method: Clinical case report and literature review. Study of a patient had an indication for permanent pacemaker implantation who had complication of subclavian artery bleeding during the procedure. Result: An 84-year-old female patient was admitted to the hospital because of fainting spells with chest pain, on the background of dangerous complex arrhythmias and ischemic heart disease, and was prescribed a pacemaker for this patient. The patient had complication occurred during the procedure, which left subclavian artery bleeding was detected and treated promptly, a cardiac pacemaker was implanted on the right side of the chest, and the patient had a successful endovascular stent cover in the left subclavian artery. Conclude: Subclavian artery bleeding is a rare complication in the procedure of permanent pacemaker implantation, but it can still occur and requires quick detection and timely treatment, needs to be successful in cardiac pacemaker placement and subclavian artery drug-eluting stent cover placement intervention. Individualized patient risk assessment is needed;appropriate and standardized intervention techniques and experience can reduce the occurrence of this variable.

Apache高可用性集群的研究与实现

高可用性集群是以减少服务间断时间为目的的一组服务节点,该系统能够最大限度地向用户提供不间断的网络服务,使集群的整体服务最大可用。文中采用Pacemaker对Apache提供集群资源管理,并用Corosync实现通信和关系管理,当集群中的某一个节点发生故障时,其他节点将在几秒钟甚至更短时间内自动接管集群资源和服务,从而不间断的向用户提供服务,最大限度地减少服务中断的时间。本系统添加了一个VIP资源,利用VIP测试Apache的高可用性。测试结果表明,该集群系统可以有效增强Apache集群服务的可用性,具有高性价比、高可靠性、高扩展性等特点。

企业级域名集群的实现与管理

域名服务系统在企业中扮演着越来越重要的角色，大量的应用系统依赖于它，采用低成本、高性能的Pacemaker＋LVS搭建高可用、负载均衡的域名服务系统，利用原有的硬件设备，大幅度地提升域名服务系统的可靠性和性能。同时，建设了统一的域名信息管理系统，简化域名管理工作，实现了域名系统一站式管理。