Cardiac Implantation Research Articles

Cardiac defibrillator implantation in patients with syncope and inducible ventricular arrhythmia: insights from the German DEVICE registry

Abstract Funding Acknowledgements Type of funding sources: None. Background Programmed ventricular stimulation may be considered for risk stratification of sudden cardiac death. The history of syncope is an independent predictor for appropriate device discharge and sudden cardiac death, but data remain sparse among different populations. Purpose The aim of this study was to assess the prognostic value of previous syncope and inducible ventricular arrhythmia (VA) during programmed stimulation in patients undergoing defibrillator implantation. Methods Among 4,196 patients enrolled in the prospective, multi-centre German DEVICE Registry undergoing defibrillator implantation, patients with syncope and inducible VA (n=285, 6.8%) vs. those with a secondary preventive indication (n=1,885, 45.2%) serving as a control group were studied. In an additional analysis of patients with inducible VA, those with vs. without (n=86, 2.1%) previous syncope were compared. Results Patients with syncope and inducible VA (64.9±14.4 years, 81.1% male) presented less often with congestive heart failure (15.1% vs. 29.1%; P<0.001) and any underlying structural heart disease (84.9% vs. 89.3%; P=0.030) with a higher left ventricular ejection fraction (43.7±14.2% vs. 38.1±14.2%; P<0.001) than patients with a secondary preventive indication (65.0±13.8 years, 81.0% male). Whereas dilated cardiomyopathy (16.8% vs. 23.8%; P=0.009) was less common in patients with syncope and inducible VA, hypertrophic cardiomyopathy (5.6% vs. 2.8%; P=0.010) and Brugada syndrome (2.1% vs. 0.3%; P<0.001) were found more frequently. Device implantation was performed more often urgently in patients with syncope and inducible VA (46.4% vs. 22.5%; P=0.005). During 1 year of follow-up, mortality (5.1% vs. 8.9%; P=0.036) and the rate of major adverse cardiac or cerebrovascular events (5.8% vs. 10.0%; P=0.027) were lower in patients with previous syncope and inducible VA compared to patients with a secondary preventive indication. Among patients with inducible VA, post-procedural adverse events including rehospitalization (27.6% vs. 21.7%; P=0.37), defibrillator shocks (16.0% vs. 15.0%; P=0.85) and recurrent syncope (3.0% vs. 0%; P=0.32) did not differ between those with vs. without syncope. Conclusions Patients with a history of syncope and inducible VA present less frequently with most cardiac comorbidities resulting in better outcomes following defibrillator implantation than patients with a secondary preventive indication. Nevertheless, patients with inducible VA experience a relevant number of post-procedural adverse events not differing between those with vs. without syncope, which underlines the importance of VA inducibility, potentially irrespective of the history of syncope.

Optimization of the clinical workflow and patient pathway in cardiac monitor implantation and follow-up

Abstract Funding Acknowledgements Type of funding sources: Private company. Main funding source(s): Medtronic Background Clinical evidence supports the use of Insertable Cardiac Monitors (ICMs) to determine the aetiology of recurrent unexplained syncope and cryptogenic stroke. ICMs continuously monitor cardiac arrhythmias, enabling appropriate diagnosis and treatment. A remote follow-up system transfers ICM data to hospital staff for analysis. This creates a significant data-burden for the staff. Purpose To assess the impact of efficiency optimization of the diagnostic patient pathway and clinical workflow for patients eligible for an ICM. Methods We collected patient-level data from all patients that received an ICM at a university hospital in 2018 and 2020 to assess the change in the clinical workflow with one year follow-up time. Pathway improvements included moving the procedure out of the catheterization lab (cath lab), switching to a nurse-led pathway as well as outsourcing part of the remote follow-up workflow to an external monitoring centre. Results The number of implanted ICMs doubled from 74 in 2018 to 159 in 2020. In 2018, all implantations were done by a physician while in 2020, 70 % were done by nurses. In 2018 the operation schedule was 60 min for an ICM, compared to 45 minutes in 2020. The waiting time from referral to implantation was significantly shorter in 2020 (mean=36 days) compared to 2018 (mean=49 days), p=0,008. Implantations done in the cath lab decreased significantly (19 % in 2018; 2 % in 2020). Patients receiving an ICM after syncope increased from 71 to 94 patients. Stroke and transient ischemic attack (TIA) as an implantation indication increased substantially from 2018 to 2020 (2 and 62 patients, respectively). In 2018, nurses analysed all remote transmissions. In 2020 the first line review and triaging of remote transmissions was outsourced to an external monitoring and triaging centre. This external service escalated only 11 % of the transmissions (204 out of 1817) to the clinic for revision. Under the assumption that a nurse uses 11 minutes per transmission as seen in previous studies, this saved 296 hours of nursing time in 2020. The nurse-led implantation in 2020 saved 48 hours of physicians’ time compared to what would have been used by the process in 2018. The shorter procedure scheduling freed up additional 40 hours of nursing time in 2020. Also, time in the cath lab was freed up for other procedures (27 hours per year). The complication rate did not change significantly (2,7 % in 2018 and 3,1 % in 2020, P=0,85). The 1-year diagnostic yield for syncope remained high in 2018 and 2020 with no statistically significant difference (26.8 % vs 20.2 % P=0.32). The diagnostic yield for stroke patients implanted in 2020 was 24.6 %. Conclusions Nurse-led care pathways and the use of an external monitoring and triaging service significantly improved the patient pathways for patients indicated for an ICM. This freed up a significant amount of staff time and resources without compromising the quality of the treatment.

Antithrombotic management in patients undergoing cardiac implantable electronic device implantation

Cardiac implantable electronic devices (CIEDs) are an established treatment option for arrhythmias, sudden cardiac death prevention, and heart failure. Approximately 1000 devices are implanted per million inhabitants in European countries each year. However, the main concern in patients with an indication for CIED implantation is frequently associated with comorbidities requiring antithrombotic medications. The invasive device implantation procedure represents a bleeding risk ranging from pocket hematoma to cardiac tamponade. On the other hand, temporary interruption of antithrombotic therapy increases the risk for thromboembolic events. Implanting CIEDs in patients on antithrombotic medications incites several clinical dilemmas of balancing thromboembolic risk against bleeding risk, as complications are associated with higher mortality rates in both aspects. The most common bleeding complication is pocket haematoma formation, which is associated with a prolonged hospital stay, higher cost, higher risk of pocket infection, and thus higher morbidity and mortality. Studies have shown that the heparin bridging strategy in patients on oral anticoagulants imposes a greater risk for pocket haematoma formation and no benefit in reducing thromboembolic events. Most procedures of CIED implantation can be performed safely with uninterrupted oral anticoagulants. Dual antiplatelet therapy increases the risk of pocket haematoma and should be avoided whenever possible.

Role Of Speckle Tracking Echocardiography In Prediction Of Responders To Cardiac Resynchronization Therapy.

To assess heart failure patients by speckle tracking echocardiography before cardiac resynchronisation therapy implantation to predict the outcome. The descriptive follow-up study was conducted at Kafrelsheikh and Mansoura University Hospitals, Egypt, from January 2020 to May 2022, and comprised heart failure patients of either gender who had ejection fraction ≤35%, QRS width ≥130msec and symptomatic even on optimal medical therapy. They were subjected to full clinical evaluation, electrocardiogram, basic and speckle tracking echocardiography with calculation of maximal septal to lateral delay at baseline and 3 months after cardiac resynchronisation therapy implantation. The patients were classified according to response into group I having non-responders, group II having patients who improved clinically only, and group III having responders both in clinical and echocardiographic terms. Data was analysed using SPSS 23. Of the 38 patients with mean age 55.24±11.23 years, 16(42%) were females and 22(57.9%) were males. There were 7(18.4%) patients in group I, 7(18.4%) in group II and 24(63.2%) in group III. There was a positive significant correlation between response to cardiac resynchronisation therapy CRT and increase in maximalseptal to lateral delay at baseline (p<0.01). There was an inverse significant correlation between response to cardiac resynchronisation therapy and decrease in maximal septal to lateral delay 3 months after the implantation (p=0.036). Maximal septal to lateral delay was found to be a good tool to predict the response to cardiac resynchronisation therapy before implantation.

Outcomes of Ventricular Tachycardia Catheter Ablation in Patients Who Underwent Cardiac Defibrillator Implantation Nationwide Readmission Database Analysis

The timing of when to perform ventricular tachycardia (VT) ablation while receiving an implantable cardioverter defibrillator (ICD) during the same hospitalization has not been explored. This study aimed to investigate the use and outcomes of VT catheter ablation in patients with sustained VT receiving ICD in the same hospital stay. The Nationwide Readmission Database 2016 to 2019 was queried for all hospitalizations with a primary diagnosis of VT with subsequent ICD during the same admission. Hospitalizations were later stratified according to whether a VT ablation was performed. All catheter ablation of VT were performed before ICD implantation. The outcomes of interest were in-hospital mortality and 90-day readmission. A total of 29,385 VT hospitalizations were included. VT ablation was performed with subsequent ICD placement in 2,255 (7.6%), whereas 27,130 (92.3%) received an ICD only. No differences were found regarding in-hospital mortality (adjusted odds ratio [aOR] 0.83, 95% confidence interval [CI] 0.35 to 1.9, p=0.67) and all-cause 90-day readmission rate (aOR 1.1, 95% CI 0.95 to 1.3, p=0.16). An increase in readmission because of recurrent VT was noted in the VT ablation group (aOR 1.53, 8% vs 5% CI 1.2 to 1.9, p <0.01); the VT ablation group encompassed a higher number of patients with heart failure with reduced ejection fraction (p <0.01), cardiogenic shock (p <0.01), and mechanical circulatory support use (p <0.01). In conclusion, the use of VT ablation in patients admitted with sustained VT is low and reserved for higher risk patients with significant co-morbidities. Despite the higher risk profile of VT ablation cohort, no differences were found in the short-term mortality and readmission rate between the groups.

Risk Factors for Infections of Cardiac Implantable Electronic Device in Saudi Arabia

Background and Objectives: Cardiac implantable electronic device (CIED) infections are increasing worldwide due to the increased use of implantable cardiac devices. (CIED) infection is a serious complication that is associated with increased mortality and morbidity as well as increased healthcare costs. However, risk factors for infection of implanted devices are poorly documented in Saudi Arabia. We aimed to determine risk factors for CIED infection in our region. Methods and Results: A retrospective study was carried out in cardiology departments at different centers in Saudi Arabia. Our population consisted of all patients with device-related infections over twenty years from January 2009 to December 2020 with one control case matched to each confirmed infection of the implanted device, resulting in 137 patients with device infection. The mean age was 58±16 years, where males constituted 75.2%. Most infections occurred in patients with the first implant. (63.5%) patients had chronic kidney disease, (59.9%) of patients had diabetes mellitus, (65%) of patients had hypertension, and (43.1%) of patients had coronary artery disease. Most of the patients had a pocket infection. Preop antibiotics were obtained in all patients before implanting. The median time from the last surgical intervention involving the device to infection symptoms was 730 days. The median length of hospitalization was 27±23 days. 130 patients survived at the time of discharge, resulting in an overall mortality rate of 5.1%. Using Multivariate analysis, we identified male gender (P = 0.000), hypertension HTN (P = 0.002), diabetes DM (P = 0.006), and presence of underlying heart disease CHD (P = 0.000) Type of the device (P = 0.000) as significantly associated with a higher risk of CIED infection. Conclusion: Our data show that gender, diabetes, hypertension, and heart disease are independent risk factors for infection after cardiac device implantation. As regards device characteristics, ICD device is associated with a higher infection rate compared to other devices.

PO-04-075 TRANSVENOUS CARDIAC DEFIBRILLATOR WITHOUT INTERACTION WITH THE MAGNETIC TITANIUM BEADS SYSTEM FOR GASTROESOPHAGEAL REFLUX DISEASE

Gastroesophageal reflux is increasingly treated with LINX®, a flexible bracelet of magnetic titanium beads (not MRI compatible) that is laparoscopically implanted to wrap around the gastroesophageal junction for providing tone/support aiding passive relaxation of a weak lower esophageal sphincter with peristalsis. The FDA currently cautions against concurrent use of the LINX® system with cardiac implantable electronic devices (CIEDs) given that the risk of electromagnetic interference (EMI) is unknown, and safety has not been established. We assessed the safety of a transvenous ICD in a patient with the LINX® system. Case Report 59 year old male who previously had the LINX® system implanted after hiatal hernia repair for refractory reflux. Shortly after, he was then diagnosed with apical hypertrophic cardiomyopathy with obstruction (NYHA Class I, genetic testing revealed VUS in CSRP3). Given non-sustained VT on cardiac event monitoring, family history of sudden cardiac death (SCD) and late gadolinium enhancement on cardiac magnetic resonance imaging with a calculated 5-year SCD risk 4.1%, he was recommended ICD implantation for primary prevention. Patient underwent an uneventful transvenous dual chamber defibrillator implantation. Although we do not routinely perform (DFT) testing at our institution, given the coexisting LINX® system in close proximity to the RV lead, we elected to proceed with DFT Testing, which was successful (1 induction: T-wave shock from sinus to VF, 30J delivered successfully to sinus with 7s charge time, no ATP, 70 ohms impedance). Patient underwent routine remote device interrogations and at 1-year follow up (which included an in-person device interrogation), continues to have normal lead parameters (sensing, impedance, threshold), minimal atrial or ventricular pacing, and no recurrent arrhythmias including NSVT (was started on verapamil). Specifically, patient received no inappropriate shocks, and no high frequency noise episodes were detected. We present the first case report of a patient who had a concomitant dual chamber ICD that was implanted shortly after a LINX device placement. We demonstrate normal DFTs at implant and no device interaction at 1 year follow-up, suggesting that ICD implantation without removal of the LINX device might be reasonable. Decision-making for cardiac device implantation decisions in such patients should consider additional theoretical risks until additional data with more patients is available.

Cardiac resynchronization therapy device implantation using suspended personal radiation protection system: Examination of radiation protection effectiveness by dosimetry at 51 exposure sites.

Cardiologists often use fluoroscopic equipment for treatment such as cardiac implantable electronic device implantation, catheter ablation, percutaneous coronary intervention, and other procedures. Difficulties arise in protecting the head and optical lens from the exposure of radiation, which is a significant concern among physicians1,2. Currently available radiation protective clothing consists of a collar for the thyroid gland and a sleeveless apron. Although higher radiation protection can be expected by increasing the lead content of the protective clothing, there is a limit to additional lead content due to the increased weight.

Early Experience of Patients with left Bundle Branch Block Corrected through Left Bundle Branch Area Pacing Compared with Conventional Right Ventricular Pacing: A Single-Center Retrospective Study.

Left bundle branch area pacing (LBBAP) has the advantages of narrow QRS duration, rapid peak left ventricular (LV) activation, and LV dyssynchrony correction with a low, stable pacing output. Here we report our experience with patients undergoing LBBAP with a left bundle branch block (LBBB) for clinically indicated pacemaker or cardiac resynchronization therapy implantation. We compared the initial follow-up data of these patients and patients undergoing conventional right ventricular pacing (RVP). This retrospective study was performed between January 2017 and December 2020 and recruited 19 consecutive patients (mean age: 63 years; 8 women, 11 men) who underwent LBBAP (13 LBBAP only and 6 LBBAP + LV pacing), and 14 consecutive patients (mean age: 75 years; 8 women, 6 men) who underwent RVP. Demographic data, QRS durations, and echocardiographic parameters were compared before and after the procedures. LBBAP substantially shortened the QRS duration and improved LV dyssynchrony echocardiographic parameters. However, RVP was not significantly associated with prolonged QRS duration and worse LV dyssynchronization. LBBAP improved cardiac contractility in selected patients. We did not find adverse effects of LBBAP on patients with preserved systolic function, possibly due to the limited number of patients and follow-up time. However, two of the 11 patients with preserved systolic function at baseline who underwent conventional RVP developed heart failure after implantation. In our experience, LBBAP improves LBBB-related ventricular dyssynchrony. However, LBBAP requires greater skill, and doubts remain about lead extraction. LBBAP may be an option for patients with LBBB when performed by an experienced operator, however further studies are needed to verify our findings.

MP-453085-11 ALLIED PROFESSIONALS DISPOSITION PATHWAY WITH CONDITIONAL DISCHARGE REDUCES BED UTILIZATION AND HOSPITAL RESOURCES

Increasing demands of inpatient level of care continue to pose challenges to hospital resources and available capacity. Alternative disposition pathways overseen by allied professionals (AP) that utilize extended recovery unit (ERU) hours and conditional discharge (CD) can reduce inpatient bed use, total time spent at the hospital and overall resource utilization. To demonstrate that implementation of disposition pathways utilizing CD and same day discharge (SDD) with an ERU reduces hospital resources without compromising patient safety. An ERU was created to reduce inpatient hospital bed utilization and optimize disposition pathways. This unit included 6 patient beds, 2 registered nurses and overnight coverage. Patients (pts) presenting for elective electrophysiology procedures were classified into three different disposition pathways including SDD, CD and admission to EP allied professional (EP AP) service. All 3 pathways were overseen by EP APs. Pts in the SDD and CD group were required to meet specific criteria noted by the AP to be considered safe for discharge. We compared these new pathways with prior disposition orders in relation to efficiency, safety and resource utilization. From 8/28/2022 to 11/13/2022, 918 pts presented for an EP procedure including cardiac device implantation and ablation. Of these, 200/918(21.8%) were eligible for our disposition pathway. There were 74(8.1%) pts who were SDD, 51(5.6%) pts in the CD pathway, 61(6.6%) pts admitted to the EP AP service, and 14(1.5%) pts were cross-over pathways (failed CD transitioned to EP AP service). The remainder were either already inpatient or felt pre-procedure to require inpatient level of care. Pts evaluated on the EP AP service in the ERU had an average discharge time of 10:04AM vs 12:53PM for pts on the EP AP service admitted to an inpatient unit. Patients in the CD group located in the ERU had an average discharge time of 7:49AM. Discharge time with these pathways improved over time (Figure 1). The total number of pts admitted to the ERU and/or discharged the same day was 186 pts, indicating 186 total hospital beds saved. There were no differences in overall complications between disposition groups compared to prior to implementation of this strategy. The implementation of a disposition pathway strategy utilizing SDD, CD and an ERU overseen by APs is associated with reduced resource utilization without compromising pt safety.

COVID-19 pandemic: Impact on the cardiac implantable electronic devices' implantation rates in Croatia.

Coronavirus disease 2019 (COVID-19) pandemic has influenced health-care organization worldwide, including management of non-communicable diseases. The aim of this study was to determine the impact of COVID-19 pandemic on cardiac implantable electronic devices' (CIEDs) implantation rates in Croatia. A retrospective, observational, national study was conducted. The data on CIEDs' implantation rates from 20 Croatian implantation centres, between January 2018 and June 2021, were extracted from the national Health Insurance Fund registry. Implantation rates before and after COVID-19 pandemic started, were compared. The overall numbers of CIED implantations in Croatia during COVID-19 pandemic were not different in comparison to 2 years pre-COVID-19 time (2618 vs. 2807, p = .081). The pacemaker implantation rates decreased significantly (by 45%) during April (122 vs. 223, p < .001) and May 2020 (135 vs. 244, p = .001), as well as during November 2020 (177 vs. 264, p = .003), but significantly increased during summer months 2020 comparing to 2018 and 2019 (737 vs. 497, p<0.001). The ICD implantation rates decreased significantly by 59% in April 2020 (26 vs. 64, p = .048). To the authors best knowledge this is a first study including complete national data on CIED implantation rates and COVID-19 pandemic impact. A significant reduction in number of both pacemaker and ICD implants during specific months of the COVID-19 pandemic was determined. However, afterwards compensation in implants resulted in similar total number when the complete year was evaluated.

Long term outcome of cardiac pacemaker implantation in pediatric population

Long term outcome of cardiac pacemaker implantation in pediatric population

Great cardiac vein occlusion following radiofrequency catheter ablation: a late complication identified during cardiac device implantation.

Great cardiac vein occlusion following radiofrequency catheter ablation: a late complication identified during cardiac device implantation.

Continuity of care and treatment intensity at the end of life in Swiss cancer patients.

Continuity of care (COC) was shown to be associated with fewer hospitalizations. We aimed to evaluate whether COC was associated with intensive intervention(s) at the end of life (IEOL), a preference-sensitive outcome, in cancer patients. The study is based on claims data of patients with incident use of anti-neoplastics in Switzerland. COC Index, Usual Provider Continuity score, Sequential Continuity index and Modified Modified Continuity Index were calculated based on consultations with the usual ambulatory care physician. Treatment intensity was evaluated in the last 6 months of life, and COC was evaluated in months 18-6 before death in those who died between 24 and 54 months after incident cancer. IEOL comprised life-sustaining interventions (cardiac catheterization, cardiac assistance device implantation, pulmonary artery wedge monitoring, cardiopulmonary resuscitation/cardiac conversion, gastrostomy, blood transfusion, dialysis, mechanical ventilator utilization and intravenous antibiotics) and measures specifically used in cancer patients (last dose of chemotherapy ≤14 days of death, a new chemotherapy regimen starting <30 days before death, ≥1 emergency visit in the last month of life, ≥1 hospital admission or spending >14 days in hospital in the last month of life and death in an acute-care hospital). All COC scores were inversely associated with the occurrence of an IEOL, as were older age, homecare nursing utilization and density of ambulatory care physicians. For COC Index, odds ratio was 0.55 (95% confidence interval 0.37-0.83). COC scores were consistently and inversely related to IEOL. The study supports efforts to improve COC for cancer patients at their end of life.

Ultrasound-guided Axillary Vein Puncture for Cardiac Device Implantation: A Safe and Effective Approach

Ultrasound-guided axillary vein access is an effective alternative to conventional subclavian and cephalic access for cardiac implantable electronic device implantation. The aim of this study was to compare the safety, efficacy, and radiation exposure data of the ultrasound-guided axillary approach with other conventional access techniques. The study population included 130 consecutive patients, stratified as 65 (64% male; median age, 79 years) in the study group and 65 (66% male; median age, 81 years) in the control group. We performed a retrospective not-randomized analysis by comparing ultrasound-guided axillary vein puncture with subclavian and cephalic approaches in order to test the effect on X-ray exposure, total procedure time, and complications. Significant differences were observed in terms of radiation exposure, including fluoroscopy time (median, 95 s [study group] vs. 193 s [control group]; P < .001), air kerma (median, 29 mGy [study group] vs. 55.7 mGy [control group]; P < .001), and dose-area product (median, 8219 mGy·cm2 [study group] vs. 16736 mGy·cm2 [control group]; P < .001). The median procedure time was 45 min in the study group but 50 min in the control group (P < .05). Complications occurred in 6 control group patients (1 urticaria contrast medium-related, 3 pneumothorax, 2 subclavian artery puncture) and 2 study group patients (2 axillary artery puncture). We conclude that the ultrasound-guided axillary venous approach is a fast, feasible, and safe technique for cardiac lead implantation. It allows a significant reduction in fluoroscopy time without prolonging the procedural time. This approach offers direct visualization of the vessel during the puncture, so it can be useful in patients who cannot receive contrast medium, those who require "difficult" thoracic approaches (emphysema, too much or too little fat tissue), or those on anticoagulant therapy.

Optimizing Cardiac Wireless Implant Communication: A Feasibility Study on Selecting the Frequency and Matching Medium

Cardiac wireless implantable medical devices (CWIMD) have brought a paradigm shift in monitoring and treating various cardiac conditions, including heart failure, arrhythmias, and hypertension. One of the key elements in CWIMD is the implant antenna which uses radio frequency (RF) technology to wirelessly communicate and transmit data to external devices. However, wireless communication with a deeply implanted antenna using RF can be challenging due to the significant loss of electromagnetic (EM) signal at the air-skin interface, and second, due to the propagation and reflection of EM waves from different tissue boundaries. The air-skin interface loss of the EM wave is pronounced due to the absence of a matching medium. This paper investigates the EM propagation losses in the human body and presents a choice of optimal frequency for the design of the cardiac implant antenna and the dielectric properties of the matching medium. First, the dielectric properties of all tissues present in the human thorax including skin, fat, muscle, cartilage, and heart are analyzed as a function of frequency to study the EM wave absorption at different frequencies. Second, the penetration of EM waves inside the biological tissues is analyzed as a function of frequency. Third, a transmission line (TL) formalism approach is adopted to examine the optimal frequency band for designing a cardiac implant antenna and the matching medium for the air-skin interface. Finally, experimental validation is performed at two ISM frequencies, 433 MHz and 915 MHz, selected from the optimal frequency band (0.4-1.5 GHz) suggested by our analytical investigation. For experimental validation, two off-the-shelf flexible dipole antennas operating at selected ISM frequencies were used. The numerical and experimental findings suggested that for the specific application of a cardiac implant with a penetration depth of 7-17 cm, the most effective frequency range for operation is within 0.4-1.5 GHz. The findings based on the dielectric properties of thorax tissues, the penetration depth of EM waves, and the optimal frequency band have provided valuable information on developing and optimizing CWIMDs for cardiac care applications.

Syncope as the initial symptom in a patient with nasopharyngeal carcinoma: a case report

BackgroundA high prevalence of nasopharyngeal carcinoma (NPC) has been found in China, but it rarely occurs with syncope. Studies have demonstrated that syncope due to NPC may be related to carotid sinus syndrome, glossopharyngeal irritation, and parapharyngeal and retropharyngeal space lesions. Such patients require evaluation by nasopharyngoscopy and head magnetic resonance imaging/computed tomography. There is no known single effective treatment for these patients. Various interventions may be considered in an effort to relieve syncope, including vasoconstrictive drugs, cardiac pacemaker implantation, radiotherapy and chemotherapy, and surgical resection.Case presentationThis case report describes a 56-year-old man who developed recurrent syncope with atrial fibrillation, a long RR interval, and hypotension. A single chamber pacemaker was fitted, but it failed to relieve the symptom. Cranial magnetic resonance imaging and pathological tests led to a final diagnosis of NPC. After six courses of chemotherapy and 35 sessions of radiotherapy, the patient became asymptomatic. However, he died from a massive uncontrolled hemorrhage in the nasopharynx two years later.ConclusionsThis case brings attention to the fact that syncope can be a symptom of NPC. Due to the insidiously malignant nature of this cancer, when a patient presents with syncope, clinicians should bear in mind this connection, albeit a rare one. There are at least two ways of treating NPC-associated syncope, but there is disagreement about which is the most effective.

Age differences of patients treated with wearable cardioverter defibrillator: Data from a multicentre registry.

Wearable cardioverter defibrillators (WCD) are used as a 'bridging' technology in patients, who are temporarily at high risk for sudden cardiac death (SCD). Several factors should be taken into consideration, for example patient selection, compliance and optimal drug treatment, when WCD is prescribed. We aimed to present real-world data from seven centres from Germany and Switzerland according to age differences regarding the outcome, prognosis, WCD data and compliance. Between 04/2012 and 03/2021, 1105 patients were included in this registry. Outcome data according to age differences (old ≥45 years compared to young <45 years) were analysed. At young age, WCDs were more often prescribed due to congenital heart disease and myocarditis. On the other hand, ischaemic cardiomyopathy (ICM) was more present in older patients. Wear days of WCD were similar between both groups (p=.115). In addition, during the WCD use, documented arrhythmic life-threatening events were comparable [sustained ventricular tachycardia: 5.8% vs. 7.7%, ventricular fibrillation (VF) .5% vs. .6%] and consequently the rate of appropriate shocks was similar between both groups. Left ventricular ejection fraction improvement was documented over follow-up with a better improvement in younger patients as compared to older patients (77% vs. 63%, p=.002). In addition, at baseline, the rate of atrial fibrillation was significantly higher in the older age group (23% vs. 8%; p=.001). The rate of permanent cardiac implantable electronic device implantation (CiED) was lower in the younger group (25% vs. 36%, p=.05). The compliance rate defined as wearing WCD at least 20 h per day was significantly lower in young patients compared to old patients (68.9% vs. 80.9%, p < .001). During the follow-up, no significant difference regarding all-cause mortality or arrhythmic death was documented in both groups. A low compliance rate of wearing WCD is predicted by young patients and patients suffering from non-ischaemic cardiomyopathies. Although the compliance rate in different age groups is high, the average wear hours tended to be lower in young patients compared to older patients. The clinical events were similar in younger patients compared to older patients.

Review of the epidemiology, pathogenesis and prevention of atrial fibrillation after pacemaker implantation.

Cardiac pacemaker implantation is an important treatment for symptomatic bradycardia. However, epidemiological data show that the incidence of atrial fibrillation (AF) is significantly higher in patients with implanted pacemakers than in the general population, which may be related to the preoperative presence of multiple risk factors for AF, improvement of diagnostic sensitivity and the pacemaker itself. The pathogenesis of AF after the implantation of pacemaker is related to cardiac electrical remodeling, structural remodeling, inflammation, and autonomic nervous disorder, which are induced by the pacemaker. Moreover, different pacing modes and pacing sites have various effects on the pathogenesis of postoperative AF. Recent studies have reported that reducing the proportion of ventricular pacing, improving the pacing site and setting up special pacing procedures might be highly useful in prevention of AF after pacemaker implantation. This article reviews the epidemiology, pathogenesis, influencing factors, and preventive measures regarding AF after pacemaker surgery.

His-Purkinje system pacing reduced tricuspid regurgitation in patients with persistent atrial fibrillation after left-sided valve surgery.

Tricuspid regurgitation after left-sided valve surgery was a common and difficult problem. Atrial fibrillation was considered to be an important etiology of tricuspid regurgitation. His-Purkinje system pacing (HPSP) was a physiological pacing method, which could prevent and treat heart failure and might reduce tricuspid regurgitation. Our study aimed to investigate the effect of HPSP on tricuspid regurgitation in patients with persistent atrial fibrillation after left-sided valve surgery. This study was a retrospective study. The 3-year patient review focused on those who underwent permanent cardiac pacemaker implantation of HPSP after mitral valve and/or aortic valve replacement from Jan 1st, 2019 to Jan 1st, 2022. HPSP included His bundle pacing (HBP) or left bundle branch pacing (LBBP). Clinical data collected included electrocardiogram, pacing parameters, ultrasonic cardiogram parameters and chest x-ray at implantation and 3-month follow up. Univariate and multivariate linear regression analysis of tricuspid regurgitation velocity were performed. A total of 44 patients was retrospectively reviewed. Eight patients who had undergone implantation of HPSP after left-sided heart valve replacement were enrolled in the study. All patients had persistent atrial fibrillation. Three of them received HBP and five underwent LBBP. At 3-month follow-up, the tricuspid regurgitation grade was significantly lower than that before implantation (P = 0.007). The tricuspid regurgitation velocity significantly decreased (317 ± 74 cm/s vs. 261 ± 52 cm/s, P = 0.022) and tricuspid valve pressure gradient (PG) reduced (42 ± 21 mmHg vs. 28 ± 10 mmHg, P = 0.040). The cardiothoracic ratio of patients was significantly lower than that before implantation (0.61 ± 0.08 vs. 0.64 ± 0.09, P = 0.017). The NYHA classification of patients also improved (P = 0.013). In multivariate liner regression analysis, the pacing ratio (β = 0.736, P = 0.037) was an independent determinant of tricuspid regurgitation velocity variation. HPSP might reduce tricuspid regurgitation and improve cardiac function in patients with persistent atrial fibrillation after left-sided valve surgery.