2017 HRS expert consensus statement on cardiovascular implantable electronic device lead management and extraction. Heart Rhythm. 2017;14:e503-e551. [PMID: 28919379 DOI: 10.1016/j.hrthm.2017.09.001]

Innovative Approach to Transvenous Lead Extraction: Bioptome and Snare Technique Without Additional Venous Access

BACKGROUND

Transvenous lead extraction (TLE) is recognized as an effective method of lead extraction, but can be challenging with old and tined pacemaker leads.

CASE SUMMARY

We present the case of a 44-year-old male with cardiovascular implantable electronic device (CIED) infection who underwent TLE of his 15-year-old tined pacemaker leads using a novel approach. A carotid shuttle sheath with the tip fashioned into a bevel shape was used as a makeshift dilator to dissect and free the leads from adhesions. A bioptome, introduced through the TightRail sheath, was employed to dislodge the right ventricular (RV) lead tip, while a snare introduced subsequently through the same access was used to grip the distal end of the RV lead. The lead was extracted using the snare without the need for additional femoral or jugular access.

CONCLUSION

To the best of our knowledge, the use of this bioptome and snare technique, through the TightRail sheath, without employing femoral or jugular access for lead extraction, has not been previously reported. This case highlights the importance of innovative techniques in successfully addressing challenging TLE cases.

Procedural and long-term outcomes of tunneled transvenous leads

BACKGROUND

Lead-related venous stenosis and occlusion can complicate the insertion or replacement of transvenous leads in patients with cardiac implantable electronic devices (CIEDs). A possible solution is to tunnel the lead from the contralateral vasculature to the ipsilateral generator. Procedural complications and long-term outcomes remain unclear with this technique.

OBJECTIVE

We sought to assess outcomes of tunneled transvenous leads.

METHODS

We retrospectively identified all patients who underwent transvenous CIED lead tunneling to a contralateral pocket at our institution between 2014 and 2024. Clinical characteristics, indications for lead implantation, postoperative complications, and long-term outcomes were collected.

RESULTS

We identified that 27 patients underwent transvenous lead tunneling at our institution. Most patients were men (20, 74%) with a mean age of 68.8 ± 18.3 years. Most patients had nonischemic cardiomyopathy (16, 59%) with a mean ejection fraction of 29.3% ± 11.3%. The tunneled leads were coronary sinus leads (20, 74%), followed by defibrillator leads (5, 18.5%) and right ventricular pacing leads (2, 7.4%). Implantation procedures were primarily for device upgrade (18), lead revisions (8), or de novo lead placement (1). No postoperative complications were seen. Patients were followed for a mean of 2.2 ± 1.4 years. One tunneled defibrillator lead (3.7%) had low shock impedance 3 years after implantation, which was monitored and did not require an intervention.

CONCLUSION

In patients with ipsilateral venous occlusion, contralateral lead tunneling appears to be an effective and safe approach to manage patients with CIEDs and occluded ipsilateral subclavian veins.

Lead Extraction-Indications, Procedure, and Future Directions

Cardiac implantable electronic device (CIED) implantation has steadily increased in the United States owing to increased life expectancy, better access to health care, and the adoption of updated guidelines. Transvenous lead extraction (TLE) is an invasive technique for the removal of CIED devices, and the most common indications include device infections, lead failures, and venous occlusion. Although in-hospital and procedure-related deaths for patients undergoing TLE are low, the long-term mortality remains high with 10-year survival reported close to 50% after TLE. This is likely demonstrative of the increased burden of comorbidities with aging. There are guidelines provided by various professional societies, including the Heart Rhythm Society, regarding indications for lead extraction and management of these patients. In this paper, we will review the indications for CIED extraction, procedural considerations, and management of these patients based upon the latest guidelines.

Management of an Exposed Cardiac Pacemaker Through the Surgical Rotational Flap

Pacemaker pocket erosion with exposure is a significant complication of cardiac implantable electronic devices, particularly in elderly patients with limited subcutaneous tissue. This case report details the successful management of a 93-year-old woman presenting with pacemaker extrusion, treated through antibiotic therapy, generator replacement, and covering with a rotation flap. This case underlines the importance of interdisciplinary collaboration and careful approaches in addressing dangerous device-related complications in fragile patients.

Efficacy and safety of negative pressure wound therapy in the treatment of patients with cardiovascular implantable electronic devices pocket infection

OBJECTIVES

To evaluate the efficacy of negative-pressure wound therapy (NPWT) for cardiac implantable electronic device (CIED) pocket infection, eliminating the need for CIED and leads extraction.

METHODS

The NPWT cohort consisted of 42 patients with CIED infection who were treated with NPWT from 2013 to 2023. Among them, 3 patients had a systemic infection and 1 patient had incomplete data. We performed a case-control study in which the NPWT group was compared with the conservative treatment group (40 patients). Main outcomes included failure rate (CIED/lead extraction during the 1-year follow-up, 30-day mortality/chronic infection, or infection-related mortality/recurrence) and infection-free time, with cure defined as absence of failure criteria.

RESULTS

A total of 38 patients with pocket infections were treated with NPWT from 2013 to 2023. NPWT was curative in 78.9% (n = 30 of 38) of patients who remained free of infection [median follow-up 12.63 months, interquartile range (IQR): 12.30-34.10 months]. Compared with patients who were treated conservatively, the two groups demonstrated balanced baseline characteristics. Patients who were treated with NPWT had a significantly higher cure rate (78.9% vs. 55.0%, n = 22 of 40; p = 0.025) and a longer mean infection-free time at the 1-year follow-up (338.00 vs. 285.20 days, p = 0.034).

CONCLUSION

NPWT is an effective alternative for patients with CIED pocket infections who are unsuitable or unwilling to undergo CIED and leads extraction.

TRIAL REGISTRATION

This study was approved by the Chinese Clinical Trial Registry (Clinicaltrials.gov number: ChiCTR2300073560) on July 07, 2023.

Transcatheter tricuspid valve replacement: will it prevail?

Severe tricuspid regurgitation (TR) is a prevalent and challenging condition associated with poor survival outcomes and significant morbidity. Medical therapy alone often fails to provide adequate symptom relief, and stand-alone surgical intervention is linked to high mortality rates, making it a less favorable option unless combined with left-sided valve surgery. The advent of transcatheter tricuspid interventions has provided new therapeutic possibilities, particularly for high-risk patients who are ineligible for conventional surgery. However, many patients are still unsuited for transcatheter tricuspid repair or have only limited benefits from such procedures. In this context, Transcatheter tricuspid valve replacement (TTVR) has rapidly emerged as a promising alternative, offering the potential for more effective treatment outcomes. This review explores the latest advancements in TTVR devices, highlights key clinical findings, and discusses the challenges and limitations of this evolving strategy. Additionally, we address patient selection criteria, procedural outcomes, and future directions in the field, emphasizing the potential of TTVR to transform the management of severe TR.

Salmonella Endocarditis: Rare Bacteremia Causing Mural Infective Endocarditis

Current guidelines do not recommend routine cardiac imaging in patients with gram-negative bacteremia, as gram-negative infective endocarditis is rare. Nongastrointestinal Salmonella infections causing endocarditis are even more uncommon, especially in the developed world. We present the case of a 60-year-old female with Salmonella bacteremia, ultimately found to have a right atrial mural endocarditis involving an implantable cardioverter-defibrillator and an indwelling venous catheter. The vegetation and indwelling devices were removed from the operating room due to the high concern of embolization if performed percutaneously, and she completed 6 weeks of antibiotic therapy. Both indwelling devices were later replaced once treatment was completed, and there was no evidence of recurrence at the 8-month follow-up. This case proves that in those with cardiac implantable electronic devices and other indwelling devices which enter the heart, who are found to have atypical bacteremia, may benefit from cardiac imaging as a part of their workup.

Superior Vena Cava Decompression After Complicated Stent Placement for Innominate Vein Obstruction in a VVI-ICD Patient

OBJECTIVES

This report discusses the challenges and strategies involved in managing venous stenosis secondary to pacing or defibrillator leads, focusing on endovascular treatment options and procedural considerations.

KEY PROCEDURAL STEPS

Crucial steps of the procedure include thorough preprocedural planning, obtaining multisite venous access for optimal angiographic visualization, wiring through the stent using a percutaneous coronary intervention wire supported by a microcatheter and guiding catheter, confirming true lumen and intraluminal wire passage, and progressive ballooning using high-pressure balloons and kissing balloon technique.

POTENTIAL PITFALLS

Procedural complications include crushing of the pacing leads within the stent, incomplete stent expansion, and aggravation of existing stenosis. Ensuring correct wire trajectory and using multiple imaging modalities are critical to avoiding these issues.

TAKE-HOME MESSAGE

Venous stenosis related to pacing leads requires a multidisciplinary approach, with careful preprocedural planning and meticulous technique.

FDG PET/CT-Guided Extraction of Infected Implantable Cardioverter-Defibrillator Causing Recurrent Stenotrophomonas Maltophilia Bacteremia

BACKGROUND

Gram-negative bacteremia rarely cause cardiac implantable electronic device infections (CIEDIs), thus challenging prompt diagnosis and device extraction.

CASE SUMMARY

A 57-year-old man with end-stage renal disease and an implantable cardioverter-defibrillator (ICD) for secondary prevention developed persistent Stenotrophomonas maltophilia bacteremia despite intravenous antibiotics and elimination of alternative infection sources. He had no pocket infection or echocardiographic evidence of endocarditis. Serial fluorine-18 fluorodeoxyglucose positron emission tomography combined with-computed tomography (18F-FDG PET/CT) demonstrated ICD seeding. The device was extracted, and the patient was treated with trimethoprim-sulfamethoxazole and levofloxacin, with bacteremia resolution. Results of intraoperative cultures confirmed device infection with S. maltophilia, a multidrug-resistant, biofilm-forming, gram-negative pathogen. The ICD was later reimplanted subcutaneously to lower the infection risk.

DISCUSSION

S. maltophilia is an emerging gram-negative organism that can cause CIEDI. 18F-FDG PET/CT can guide CIEDI diagnosis when a patient has occult bacteremia and uncertain device seeding.

TAKE-HOME MESSAGE

Maintain suspicion for cardiac device involvement in S. maltophilia bacteremia and use FDG PET CT when CIEDI is unclear.

Implantation and Follow-Up of an Extravascular ICD After a Challenging Transvenous System Extraction: A Case Report

The Extravascular ICD (EV-ICD) is implanted outside of the patient's heart and vascular system. The defibrillation lead is tunneled in the substernal space, very close to the surface of the heart, thus allowing for additional pacing capabilities such as Post Shock Pacing, Anti-Tachycardia Pacing (ATP), and Pause Prevention Pacing. Early studies demonstrated the safety and efficacy profile of the EV-ICD, but patients with previous or existing cardiac devices or leads were excluded. In this case report we describe the implantation of an EV-ICD in a 68-year-old male patient, who had undergone a challenging extraction of a previous transvenous system due to infection and screened negative for a subcutaneous ICD (S-ICD). Given the lack of upper and lower venous accesses, it was also necessary to implant an epicardial bipolar lead connected to a single-chamber pacemaker as a backup during extraction, which also remained in place chronically. Follow-up was uneventful through the following 10 months, with stable system parameters and no infection relapse.

Brucella suis Infection in Cardiac Implantable Device of Man Exposed to Feral Swine Meat, Florida, USA

Brucella suis infection in the United States is typically from feral swine exposure. We describe a case of B. suis cardiac implantable device infection in a man exposed to meat and blood from feral swine in Florida, USA. The infection was diagnosed using culture, molecular diagnostics, and whole-genome sequencing.

Multicentric Experience With the Use of Short 13Fr Mechanical Rotating Dilator Sheath for Transvenous Lead Extraction

BACKGROUND

The need for transvenous lead extraction (TLE) is increasing worldwide. Since the course of the subclavian vein until the junction with the superior vena cava is a frequent place of lead adherences, we aim to assess the safety and efficacy of a short 13Fr bidirectional rotational mechanical sheath as first choice.

METHODS AND RESULTS

In this multicentric study, 202 carriers of a cardiac implantable electronic device (CIED) undergoing TLE using a short 13 Fr bidirectional rotational mechanical sheath were prospectively enrolled. All procedures were performed using a stepwise approach. The indication for TLE were infection (62%), malfunction (32%), and upgrade (6%). Overall, 471 leads were extracted: 65% pacing leads, 20% defibrillator leads, 9% coronary sinus leads, and 6% abandoned leads. Clinical success and complete lead extraction have been achieved in 97% and 95% of cases, respectively. The short sheath was always effective in gaining venous access at the start of the procedure and was sufficient for complete TLE in 67% of cases. Lead dwell time, defibrillator lead, number of leads per patient, and lead malfunction were predicting factors of long bidirectional rotational mechanical sheath use. There were no cases of intraprocedural death, and major complications were reported in 2% of patients. Overall survival was 97% at 1-year follow-up.

CONCLUSION

This multicentric experience using a short 13Fr bidirectional rotational mechanical sheath reported high safety and efficacy, demonstrating the utility of routine use of short extraction sheaths of higher caliper as the first choice.

Clinical profile and outcomes among patients with cardiac implantable electronic device presenting as isolated pocket infection, pocket-related infective endocarditis, or lead-related infective endocarditis

AIMS

The clinical spectrum of cardiac implantable electronic device (CIED) infections includes isolated pocket infection (IPI), pocket infection complicated by infective endocarditis (PIRIE), and lead-related infective endocarditis (LRIE). The aim of this study was to assess the risk factors, clinical course, and outcomes in patients with CIED infections and to demonstrate differences between PIRIE and LRIE.

METHODS AND RESULTS

The retrospective analysis of data from 3847 patients undergoing transvenous lead extraction for non-infectious (2640; 68.62%) and infectious (1207; 31.38%) indications, including 361 (29.91%) IPI, 472 (39.11%) PIRIE, and 374 (30.99%) LRIE, showed some differences in risk factors, clinical course, and outcomes between the subgroups. Unlike PIRIE, diabetes [hazard ratio (HR) = 1.488; 95% confidence interval (CI; 1.178-1.879), P < 0.001] and lead abrasion [HR = 2.117; 95% CI (1.665-2.691), P < 0.001] increased the risk of LRIE. The risk of pocket infection spread was greater with Staphylococcus aureus infection [HR = 1.596; 95% CI (1.202-2.120), P < 0.001]. Compared with LRIE, patients with PIRIE had lower levels of inflammatory markers and lower prevalence of vegetations. Mortality in PIRIE compared with LRIE patients was lower (53.18 vs. 62.30%; P < 0.001) and comparable to IPI (50.69%; P = 0.162) at long-term [median 1828 (815-3139) days] follow-up.

CONCLUSION

Cardiac implantable electronic device infections share common risk factors; however, diabetes and intra-cardiac lead abrasion predispose to LRIE, whereas multiple leads and S. aureus in pocket culture are risk factors for pocket infection spread. Compared with LRIE, the clinical course of PIRIE was milder, and short- and long-term mortalities were lower, but comparable with IPI after >1 year. This may be an argument in favour of categorization into primary LRIE and secondary endocarditis, i.e. PIRIE.

Right Bundle Branch Block After Transvenous Lead Extraction: An Unreported Complication With Potentially Severe Outcomes

INTRODUCTION

Right bundle branch block (RBBB) following cardiac device extraction has not been previously reported but may have catastrophic consequences.

METHODS AND RESULTS

We present two cases of young male patients who developed RBBB following the extraction of single chamber TV ICD systems where the coil was adherent close to the superior tricuspid valve annulus. Both patients had a subcutaneous ICD (SICD) implanted but suffered an inappropriate shock due to T-wave oversensing, requiring very early SICD removal for one patient.

CONCLUSION

The development of RBBB following the extraction of a TV ICD is a previously unreported complication and may cause significant sensing problems if an SICD is implanted subsequently. Placement of the ICD lead tip in the right ventricular outflow tract or high on the intraventricular septum may predispose to this complication.

Transvenous extraction of quadripolar coronary sinus pacing leads

BACKGROUND

Quadripolar coronary sinus (CS) leads are commonly employed to achieve left ventricular pacing. There are limited data on extraction of these leads relative to traditional unipolar or bipolar CS pacing leads.

OBJECTIVE

The purpose of this study was to examine the safety and efficacy of quadripolar CS lead extraction and CS lead reimplantation and to compare outcomes with extraction of non-quadripolar CS leads.

METHODS

Patients who underwent extraction of CS leads between 2013 and 2024 were included. Outcomes of interest were rates of complete CS lead removal, complete procedural success, major adverse events, and successful reimplantation in the CS.

RESULTS

A total of 182 patients were included (102 quadripolar leads and 80 non-quadripolar leads). The mean age of the patients was 68.0 ± 11.6 years, and 22% were female. The mean CS lead age was significantly lower in the quadripolar group (3.0 ± 2.7 years vs 8.2 ± 4.3 years; P < .001). The complete procedural success rate was significantly higher in the quadripolar group (99% vs 90%; P = .01); there was no difference between groups after accounting for lead age. There was no significant difference in complete CS lead removal rates between groups (99% vs 95%; P = .17). Two major adverse events occurred in the non-quadripolar group and were directly related to lead extraction. In the quadripolar group, manual traction alone was successful in 59%, laser sheaths were used in 39%, and rotational cutting tools were used in 9%. In the non-quadripolar group, manual traction alone was successful in 19%, laser sheaths were used in 79%, and rotational cutting tools were used in 26%. There was no significant difference in reimplantation success rates between groups (82% vs 90%; P = .30).

CONCLUSION

Quadripolar CS lead extraction had a high success rate and low rate of major adverse events. Reimplantation in the CS was possible with a good success rate but was often limited by CS branch stenosis or occlusion.

Long-Term Complications Related to Cardiac Implantable Electronic Devices

Cardiac implantable electronic devices (CIEDs) are commonly used for a number of cardiac-related conditions, and it is estimated that over 300,000 CIEDs are placed annually in the US. With advances in technology surrounding these devices and expanding indications, CIEDs can remain implanted in patients for long periods of time. Although the safety profile of these devices has improved over time, both the incidence and prevalence of long-term complications are expected to increase. This review highlights pertinent long-term complications of CIEDs, including lead-related issues, device-related arrhythmias, inappropriate device therapies, and device-related infections. We also explore key clinical aspects of each complication, including common presentations, patient-specific and non-modifiable risk factors, diagnostic evaluation, and recommended management strategies. Our goal is to help spread awareness of CIED-related complications and to empower physicians to manage them effectively.

Contemporary use of non transvenous ICD

Sudden cardiac death can be prevented by defibrillator therapy. Non transvenous ICD mitigates risks associated with transvenous ICD. In this review, we discuss different types of non-transvenous ICD, their use in current clinical practice, and their limitations.

Left Ventricular Assist Device Versus Cardiac Implantable Electronic Device Infections: Distinct Entities, Distinct Suppression Strategies

A distinction between infections of left ventricular assist devices and cardiac implantable electronic devices is warranted as they differ markedly in incidence, microbiologic profiles, clinical presentations, and extraction feasibility. These differences necessitate tailored suppressive antibiotic therapy (SAT) strategies. This commentary highlights the need for device-specific SAT approaches.

Pacemaker lead fracture caused by strong lead bending in the pocket with the fixation of the generator in the low prothoracic position

Lead fractures of pacemakers can occur over time. However, the entire mechanisms or sites of lead fractures remain unclear. In addition, fixation of the pacemaker generators and leads depends on the operators and the tips on proper fixation remain unclear. A 64-year-old male underwent permanent dual-chamber pacemaker implantation for complete atrioventricular block by extrathoracic axillary vein puncture eight years previously. The generator was routinely fixed to the pectoralis major muscle within the left anterior chest pacemaker pocket by suturing a nylon ligature through the suture hole. However, five months ago, complete atrial lead failure was confirmed. The chest X-ray and X-ray fluoroscopy revealed strong lead bending of the atrial lead in the pacemaker pocket with the fixation of the generator in the low prothoracic position. We successfully extracted the fractured atrial lead by using an excimer laser and implanted a new atrial pacemaker lead in the right atrium. In the extraction of the fractured atrial lead, the atrial lead was almost disconnected along with strong lead bending in the pacemaker pocket as expected from preprocedural X-rays. This report indicates the precautions in fixation of pacemaker leads in the pacemaker pocket.

Learning objective

The stress-free fixation of pacemaker leads should be cautious to avoid the risk of lead failure in the long-term after the procedure. In addition, less tortuous vascular lead path, more caudal can location, and large angle of lead exit from the pocket associated with the puncture site or angle of axillary vein in the pacemaker implantation can cause strong lead bending and lead fractures. These findings can be detected in the X-ray.

Efficacy and safety of mechanical transvenous lead extraction: median follow-up analysis and development of an experimental model for predicting survival post-extraction

BACKGROUND

Cardiac implantable electronic device (CIED) implantation is on the rise, accompanied by an increase in its inevitable complications such as different types of CIED infections that require further therapy and potential device extraction. Ensuring efficacy and safety remains paramount in transvenous lead extraction (TLE), given the complex nature of the procedure. The purpose of this study is to assess the outcomes of relatively low-cost mechanical TLE, including mid-term clinical follow-up, and to develop a predictive model for post-TLE survival. This study included all consecutive patients admitted for TLE at two tertiary medical centers between 2016 and 2021. Baseline characteristics, TLE procedure details complications occurring during and/or after the procedure and follow-up outcomes were collected.

RESULTS

During the 5-year period, 100 consecutive patients underwent TLE. The mean age of the subjects was 61 ± 3 years. The average time from lead implantation to TLE was 69.34 ± 9.36 months, with a total of 216 leads extracted. The most common indication for TLE was infection observed in 87% of subjects with pocket infection seen in the majority (84%). Complete clinical success was achieved in 98% of patients, with major complications occurred in 5% of cases and only one case of peri-procedural death. Proposed experimental model showed that near 50% of the patients will live less than 73.29 months.

CONCLUSION

TLE demonstrated a high level of safety with low mortality and morbidity rates. Using low cost widely available mechanical tools is useful for treating CIED-related infections.

Pacing considerations in patients undergoing transcatheter tricuspid valve replacement: Insights from a tertiary care center

BACKGROUND

Patients requiring transcatheter tricuspid valve replacement (TTVR) often have a preexisting pacemaker lead crossing the tricuspid valve (TV). TTVR could also lead to heart block.

OBJECTIVE

We aimed to describe pacing considerations in patients referred for TTVR.

METHODS

We identified patients who underwent TTVR at Emory Healthcare. Clinical characteristics including presence of preexisting pacemaker leads, management of these TV leads at the time of TTVR, and pacing requirements after TTVR were collected.

RESULTS

Seventy-three patients underwent TTVR; 21 (29%) patients had preexisting permanent pacing systems (19 transvenous leads and 2 leadless pacemakers [LPs]). In 14 patients (73.7%), the transvenous lead was jailed. Five patients (26.3%) underwent lead extraction and implantation of a TV-sparing pacing system (n = 2) or ventricular LP (n = 2), whereas 1 patient did not undergo device reimplantation. After TTVR, 7 of 52 patients had heart block requiring permanent pacing (13%); 4 patients received an LP, 2 patients had a TV-sparing pacemaker implanted, and 1 had a lead implanted across the valve. During an average follow-up of 10.5 months, complications were reported in 3 of 14 patients with jailed leads (21%). Two patients required fractured lead revision. One of the revisions was complicated by infection, which resulted in the patient's death. A patient with a jailed right ventricular lead died suddenly 1 week after discharge.

CONCLUSION

More than 20% of patients with jailed leads after TTVR have serious complications due to lead malfunctions. TTVR-related heart block was common in our cohort (13%), and its treatment with LP or TV-sparing pacing systems was safe and effective.

New Diseases Related to Cardiac Implantable Electronic Devices (CIEDs): An Overview

The widespread use of Cardiac Implantable Electronic Devices (CIEDs) has transformed the management of cardiac arrhythmias, improving survival and quality of life for millions. However, this progress has introduced a range of device-related complications, which can significantly impact patient outcomes. This review examines "new diseases" linked to CIEDs, categorizing them into physical (e.g., infections, venous obstruction, lead failure, and device recalls) and functional complications (e.g., arrhythmias, pacemaker syndrome, and left ventricular dysfunction). Prevention and management strategies are emphasized. Emerging technologies, such as leadless devices, quadripolar leads, and remote monitoring systems, hold promise in reducing risks and enhancing patient care. Future directions include integrating artificial intelligence for real-time monitoring, improving device durability, and exploring novel materials to minimize infections and mechanical failures. Understanding CIED-related complications is essential for healthcare providers to balance the benefits and risks of these life-saving technologies.

When pacing or defibrillator leads become redundant: Extract or abandon?

The 2017 Heart Rhythm Society expert consensus paper on lead management and extraction did not express a preference for either extracting or abandoning pacing or defibrillator leads that are dysfunctional or superfluous after an upgrade (hereafter referred to as redundant leads). However, no randomized or even nonrandomized trials show a better patient outcome with extraction. Many experienced centers currently advise patients to have redundant leads removed to prevent more complicated procedures after years of abandonment. According to the literature, however, not all abandoned leads need to be extracted as >90% will have an uneventful follow-up. As immediate extraction of redundant leads has a small but significant risk, this will generate more adverse events at the population level than when extraction is limited to the patients with future lead complications, even considering a higher extraction risk at that time. Lead extraction is also limited to specialized centers and often necessitates expensive tools, in contrast to abandoning leads, which can be safely performed by any experienced device specialist without additional cost.

The Long-Term Outcomes of Inactive Pacemaker Lead Abandonment in Children and Dramatic Observation of Complications

Transvenous extraction of the leads in children is associated with a higher risk of serious complications, that is why it is reluctantly performed. Unfortunately, this conservative approach has been associated with secondary complications (tricuspid valve dysfunction and bilateral venous obstruction), adverse events during lead removal procedure and recanalization and stenting of chest veins. We present a case of a 27-year-old female with a pacemaker and insertion of two new leads on the opposite side of the chest leaving the old ones in place.

Managing superior vena cava syndrome in patients with cardiac implantable electronic device leads: Strategies and considerations

BACKGROUND

Data on transvenous (TV) lead-associated superior vena cava (SVC) syndrome are limited. The management of this problem might require a multidisciplinary approach, often involving transvenous lead extraction (TLE) followed by angioplasty and stenting.

OBJECTIVE

The purpose of this study was to describe the management and outcome of TV lead-associated SVC syndrome.

METHODS

We retrospectively identified patients with a diagnosis of SVC syndrome and TV leads at Emory Healthcare between 2015 and 2023.

RESULTS

Fifteen patients with lead-related SVC syndrome were identified. The cohort average age was 50 years. Symptoms included swelling of the face, neck, and upper extremities (67%); shortness of breath (53%); and lightheadedness (40%). Patients had an average of 2 ± 0.7 leads crossing the SVC, with a lead dwell time of 9.8 ± 7.5 years. Thirteen patients were managed with TLE, followed by SVC stenting and angioplasty in 10 and angioplasty alone in 2; 1 patient had no intervention after TLE. One patient was managed with anticoagulation, and another had angioplasty and stenting with lead jailing. One patient experienced SVC perforation and cardiac tamponade during SVC stenting, which was managed successfully with a covered stent and pericardiocentesis. Among the 12 patients with TLE and angioplasty ± stenting, 7 underwent reimplantation of a transvenous lead. Two of those patients had symptoms recurrence, and none of the 5 patients without lead reimplantation had recurrence of symptoms.

CONCLUSION

Lead-related SVC syndrome management requires a multidisciplinary approach often including TLE followed by angioplasty and stenting. Avoiding TV lead reimplantation might help reduce symptoms recurrence.

A Novel Approach to Identifying Appropriate Candidates for Transvenous Lead Extraction

BACKGROUND

The need for transvenous lead extractions (TLEs) in the setting of cardiac implantable electronic device-(CIED) related infections continues to rise. Delays in referral for TLE in this setting are common and are associated with increased mortality.

OBJECTIVE

To describe the outcomes of a comprehensive approach, including an electronic medical record (EMR)-based notification algorithm designed to identify patients with active CIED-related infections to facilitate timely TLE.

METHODS

Following an interdepartmental education initiative at a high-volume extraction center, an EMR based notification algorithm generated alerts for all inpatients with a CIED who received intravenous antibiotics or had positive blood cultures between September 2022 and February 2024. Patients deemed to be high risk underwent an electrophysiology consultation and were managed at the discretion of the treating electrophysiologist. Demographics, procedural details, and clinical outcomes were analyzed.

RESULTS

1829 notifications were screened over the study period. Thirty-nine consults were generated (2%). Of these patients, 18 TLEs were performed (46%). Patients who underwent TLE had MSSA (56%), MRSA (22%), enterococcus (11%), Serratia (5.6%), or S. gallolyticus (5.6%) bacteremia. The median time from the review to consultation was 1 day (IQR: 0, 1 days) and review to TLE was 2 days (IQR: 1, 2.75 days). Survival in the extraction group was 67% after a median follow-up period of 133 days (IQR: 59, 223 days).

CONCLUSION

A comprehensive approach, including an EMR-based notification algorithm allowed for the early identification of patients who were appropriate candidates for TLE due to CIED-related infections. Use of this algorithm facilitated timely TLEs.

Pocket Perforation Using 3-0 Nylon Suture for Device Fixation

Device infection occurs at a rate of 1.5%, and age over 65 years is considered a risk factor. If a pacemaker infection occurs, it is recommended that both the generator and pacing lead be removed, which is a highly invasive complication that should be avoided. We report the case of an 83-year-old man whose 3-0 nylon suture used to fix the generator had perforated the body surface four years after pacemaker implantation. Fortunately, there was no evidence of infection, and thus we were able to repair the perforated portion of the nylon suture and replace the generator without removing the pacing lead. The patient had a body mass index (BMI) of 20.4 kg/m2 at the time of pacemaker implantation, but over the course of four years, the patient's BMI had progressively decreased to 18.4. The tip of the nylon suture was sharp, and the thinning of the subcutaneous tissue caused the tip of the nylon suture to perforate the skin. In this case, only the nylon suture protruded through the skin, reminding us of the strong penetrating power of the nylon tip. Preventive measures that are easy for physicians to implement include the use of thin nylon sutures with low penetration force for fixation. It is recommended to use silk sutures when fixing the generator, as the cut ends of the silk sutures are not sharp, and to fix the generator so that a knot is formed at the back. Also, implant a leadless pacemaker. We need to be careful because the number of pacemakers implanted in thin elderly patients is expected to increase in the future.

Efficacy of transcatheter edge-to-edge repair for cardiac implantable electronic device-associated tricuspid regurgitation: insights from the TRI-SPA registry

INTRODUCTION AND OBJECTIVES

This study aimed to assess the effectiveness and clinical outcomes of tricuspid transcatheter edge-to-edge repair (T-TEER) in patients with cardiac implantable electronic devices (CIEDs).

METHODS

This subanalysis of the Transcatheter Tricuspid Valve Repair in Spain (TRI-SPA) registry included patients with at least severe tricuspid regurgitation (TR) who were treated with T-TEER between June 2020 and May 2023 in Spain. Patients with CIEDs and no or mild tricuspid lead-leaflet interaction were compared with those without CIEDs. The primary composite endpoint was all-cause mortality, heart failure-related hospitalization, and tricuspid valve reintervention at 12 months.

RESULTS

Among 310 patients (mean age 75.5±9.1 years, 70% female) with significant TR treated with T-TEER, 35 (11%) had CIEDs. Device implantation success was high in both groups (97.1% in the CIED group vs 96.4% in the non-CIED group, P=.81), with a similar rate of ≤2+ residual TR (84.9% in the CIED group vs 91.0% in the non-CIED group, P=.26). Patients with CIEDs experienced comparable rates of the primary composite endpoint to the non-CIED group (23.8% vs 19.1%, respectively, HR, 1.40; 95%CI, 0.60-3.31; P=.44), sustained successful TR reduction (δ 2+ in 55.0% vs 73.8%, P=.07), and functional improvement (NYHA class I/II 81.8% vs 79.9%, P=.79).

CONCLUSIONS

In a real-world setting, T-TEER seems to be an effective therapeutic option for selected patients with more than moderate TR and CIEDs with no or mild lead-leaflet interaction, offering comparable cardiovascular outcomes and clinical improvement to those without leads. However, the presence of CIEDs may represent an independent risk factor for TR recurrence.

Challenges in extracting a defective ventricular lead after CRT-D: a case report

Background

Our aim in this case was to remove the defective ventricular lead and the ruptured coronary sinus lead.

Methods

Entering through the right femoral vein and removing the coronary sinus lead with a pigtail catheter.

Results

In our attempt to extract the coronary sinus lead, it fractured. The broken fragment was successfully removed without any complications.

Conclusions

In this case, which is very rarely encountered in daily practice, we successfully removed the coronary sinus lead from the body from the femoral vein using a pigtail catheter with a new method.

Removal of Spontaneously Fractured Leads with Their Proximal Ends in the Heart and Vasculature-Description of Different Approaches and Tools

Background: Removal of spontaneously fractured leads with their proximal ends migrated into the vascular space has not been analysed in detail thus far. The study aimed to compare the effectiveness of different approaches and auxiliary tools for removing fractured leads with migrated proximal ends. Methods: Retrospective analysis of 72 cases from a database containing 3847 TLEs (transvenous lead extraction). Results: Most of the leads were passive, especially unipolar. Procedure complexity in such cases was high but with satisfying effectiveness (procedural success rate 93.06%) and independent of the position of the proximal end. The rate of major complications was 2.78%, which may be attributed to long implant duration (152.2 months). Extraction of such leads did not influence long-term survival. The femoral approach was most often used (62.50%). In 79.16% of leads, mechanical dissection was required. In 66.7%, proximal ends were strongly attached to the wall, and a loop had to be applied. In 15.28% of procedures, the lead was wrapped around a pig-tail catheter ("spaghetti twisting technique"). Conclusions: (1) Spontaneous lead fracture with the proximal ends migrated into the vascular space is a rare finding (1.87% of the TLE). (2) Removal of such leads requires the use of different approaches as well as dedicated and non-dedicated tools. (3) Despite a high level of procedure complexity, its effectiveness is high, with an acceptable rate of major complications.

Prevalence of metal implants among US adults aged 40 years and older

Metal implants are commonly used in clinical practice. However, little is known regarding the prevalence of metal implants. Therefore, this study aimed to evaluate the prevalence of metal implants in the United States (US) among individuals aged ≥ 40 years. This study conducted a serial cross-sectional analysis of US adults aged ≥ 40 years who participated in the National Health and Nutrition Examination Survey (NHANES) (2015-2016 and 2017-March 2020). Self-reported questionnaires were used to assess whether the participants had metal implants inside their bodies. The primary outcome was the prevalence of metal implants among adults aged 40 years and older. Furthermore, weighted logistic regression analysis was employed to determine the changes in the prevalence of metal implants from 2015 to March 2020. Moreover, this study investigated the variation in metal implant prevalence by demographic factors based on the pooled NHANES cycles. All analyses were conducted based on 3,736 participants from the NHANES 2015-2016 and 6,387 participants from the NHANES 2017-March 2020. This study observed a high prevalence of metal implants among adults aged 40 and older (2015-2016: 27.23%; 2017-March 2020: 31.53%). Moreover, the results of the weighted logistic regression analysis showed that the prevalence of metal implants significantly increased from 2015 to March 2020, especially among older individuals, men, and White individuals. In addition, the results of the weighted logistic regression analysis indicated that the metal implant prevalence differed by age and race/ethnicity, in which older individuals and White individuals showed a significantly higher prevalence of metal implants than younger individuals and non-White individuals, respectively. There was a high prevalence of metal implants among US adults aged 40 and older, and the prevalence of metal implants significantly increased from 2015 to March 2020. Therefore, more attention needs to be paid to this special population, and it may be necessary to ensure accessibility and affordability and assess the potential long-term health impacts of metal implants, considering the increased prevalence of metal implants.

Lead Longevity in Pediatric and Congenital Heart Disease Patients: The Impact of Patient Somatic Growth

BACKGROUND

Pacemakers and implantable cardioverter-defibrillators in pediatric and congenital heart disease (CHD) patients may be required for decades. In this population, there are sparse data on long-term lead functionality.

OBJECTIVES

The aims of this study were to assess pacemaker and defibrillator lead survival in pediatric and CHD patients beyond 10 years after implantation and to identify patient- and lead-related factors associated with earlier lead failure.

METHODS

This was a retrospective study reviewing all patients with a pacemaker or defibrillator who received care at a single large children's hospital during a 30-year timespan. The log-rank test and Cox proportional hazards model were used to identify risk factors associated with earlier lead failure.

RESULTS

Data were collected from 952 leads in 396 patients. Overall lead survival was 87% at 10 years, 78% at 15 years, and 69% at 20 years. Male sex, younger patient age, greater somatic growth, left ventricular lead location, and epicardial implantation approach were associated with higher likelihood of lead failure (log-rank test P <0.05). On multivariate analysis, the most significant predictor of lead failure was patient somatic growth ≥5 cm/year (HR 3.33; 95% CI: 1.78-6.25). The presence of CHD, lead insulation, and lead manufacturer had no impact on lead longevity.

CONCLUSIONS

Greater patient somatic growth is an important predictor of lead failure. Greater somatic growth may account for the observation in this study (and prior studies) that leads in male patients, younger patients, and implanted via epicardial approach were more likely to fail.

Complications of transvenous lead extraction-focus on tricuspid valve damage: a case report

Background

Transvenous lead extraction (TLE) has become an essential component of lead management strategies, but it carries the risk of severe complications, including damage to the tricuspid valve. Currently, there are no established predictors that can help prevent these complications.

Case summary

An 84-year-old male with a dual-chamber pacemaker was admitted to the hospital due to a pocket fistula resulting from a local infection. Approximately 1 year prior, he underwent the implantation of a new ventricular lead and pacemaker replacement due to lead damage and battery depletion. Another lead had been abandoned. The patient underwent a procedure to remove the entire pacing system, which was complicated by tricuspid leaflet avulsion, resulting in acute and severe tricuspid regurgitation. A biological valve was successfully implanted to replace the damaged valve. Twenty days later, a new pacing system was implanted, which included one atrial lead and another positioned in the posterolateral coronary vein of the left ventricle. Post-procedural transthoracic echocardiography (TTE) showed the biological valve in place at the tricuspid orifice, with no regurgitation and preserved ejection fraction. Following recovery, the patient was discharged in good condition.

Discussion

While pre-procedural TTE and intra-procedural transesophageal echocardiography are commonly used to identify lead-induced tricuspid insufficiency, they often do not clarify the underlying mechanisms or predict potential complications during TLE. To address this issue safely, further research into new imaging techniques is necessary, as some existing methods may not be adequate in certain situations.

Lead Extraction in Children and Young Adults: When is the Best Time for Lead/System Replacement?

The best strategy for lead management in children is a matter of debate, and our experiences are limited. This is a retrospective single-center study comparing difficulties and outcomes of transvenous lead extraction (TLE) implanted ich childhood and at age < 19 years (childhood-implanted-childhood-extracted, CICE) and at age < 19 (childhood-implanted-adulthood-extracted, CIAE). CICE patients-71 children (mean age 15.1 years) as compared to CIAE patients (114 adults (mean age 28.61 years) were more likely to have VVI than DDD pacemakers. Differences in implant duration (7.96 vs 14.08 years) appeared to be most important, but procedure complexity and outcomes also differed between the groups. Young adults with cardiac implantable electronic device implanted in childhood had more risk factors for major complications and underwent more complex procedures compared to children. Implant duration was significantly longer in CIAE patients than in children, being the most important factor that had an impact on patient safety and procedure complexity. CIAE patients were more likely to have prolonged operative duration and more complex procedures due to technical problems, and they were 2-3 times more likely to require second-line or advanced tools compared to children, but the rates of clinical and procedural success were comparable in both groups. The difference between the incidence of major complications between CICE and CIAE patients is very clear (MC 2.9 vs 7.0%, hemopericardium 1.4 vs 5.3% etc.), although statistically insignificant. Delay of lead extraction to adulthood seems to be a riskier option than planned TLE in children before growing up.

Leadless pacemaker implantation after delayed atrial lead perforation and battery depletion: a case report

BACKGROUND

Delayed lead perforation is a rare complication of cardiac implantable electronic device (CIED). Clinical presentations range from completely asymptomatic to pericardial tamponade. Surgical lead extraction is recommended and transvenous lead extraction (TLE) with surgical backup is an alternative method.

CASE PRESENTATION

A male with paroxysmal atrial fibrillation and sick sinus syndrome implanted a dual-chamber pacemaker with two passive fixation lead. He was on oral anticoagulants and played golf for almost 1 h every day after implantation. However, he complained of thoracic stabbing in the sternal manubrium with abnormal findings on pacemaker interrogation. Imaging confirmed the perforated atrial electrode with lead tip protrusion from the pericardium adjacent to the inferior wall of the main right pulmonary artery, but without pericardial effusion. Lead removal by TLE with surgical support was suggested, but he refused. Given the stable conditions, conservative treatment was chosen in the absence of complications during a follow-up period of 14 years. Then ventricular lead failure and battery depletion appeared and a leadless pacemaker was implanted.

CONCLUSIONS

Chest pain in CIED with abnormal electrical parameters, especially ongoing treatment with anticoagulants and regular physical activity, should always raise suspicion of lead perforation. A conservative strategy may be appropriate and feasible for those in the absence of perforation-related complications. For patients with noninfectious abandoned leads and battery depletion after CIED, leadless pacemaker may be an alternative approach according to patient and provider preferences.

Impact of hospital lead extraction volume on management of cardiac implantable electronic device-associated infective endocarditis

AIMS

Utilization of transvenous lead extraction/removal (TLE) for the management of cardiac implantable electronic device (CIED)-associated infective endocarditis (IE) remains low. The aim of this study was to examine the impact of hospital TLE procedural volume on TLE utilization and outcomes for patients with CIED-associated IE.

METHODS AND RESULTS

Using the Nationwide Readmissions Database, we evaluated 21 545 admissions for patients (mean age 70 years, 39% female) with CIEDs hospitalized with IE at TLE centres. Hospitals were categorized based on annual volume tertiles: (i) low-volume (1-17 TLEs/year), (ii) medium-volume (18-45 TLEs/year), and (iii) high-volume centres (>45 TLEs/year). Between 2016 and 2019, 57% of admissions in the study were to low-volume TLE centres. Transvenous lead extraction/removal was performed during 6.9, 19.3, and 26% of admissions for CIED-associated IE at low-, medium-, and high-volume TLE centres, respectively (P < 0.001). After adjustment for age and comorbidities, hospitalization for IE at high-volume centres was independently associated with TLE when compared with low-volume centres (adjusted odds ratio 4.26; 95% confidence interval 3.53-5.15). Transvenous lead extraction/removal-associated complication rates were similar at 2.5, 2.3, and 3.4% at low-, medium-, and high-volume centres, respectively (P = 0.493). Overall inpatient mortality during admissions to low-, medium-, and high-volume centres was also similar.

CONCLUSION

Admissions to high-volume TLE centres were associated with higher utilization of TLE for management of CIED-associated IE. Transvenous lead extraction/removal-associated complications and mortality among patients hospitalized with CIED-associated IE were similar when stratified by hospital TLE volume, but this needs to be considered in context of significant differences in patient comorbidity burden between centres.

Improved myocardial scar visualization using free-breathing motion-corrected wideband black-blood late gadolinium enhancement imaging in patients with implantable cardiac device

PURPOSE

The purpose of this study was to introduce and evaluate a novel two-dimensional wideband black-blood (BB) LGE sequence, incorporating wideband inversion recovery, wideband T2 preparation, and non-rigid motion correction (MOCO) reconstruction, to improve myocardial scar detection and address artifacts associated with implantable cardioverter defibrillators (ICDs).

MATERIALS AND METHODS

The wideband MOCO free-breathing BB-LGE sequence was tested on a sheep with ischemic scar and in 22 patients with cardiac disease, including 15 with cardiac implants, at 1.5 T. Wideband MOCO free-breathing BB-LGE sequence was compared with conventional and wideband breath-held PSIR-LGE and conventional and wideband breath-held BB-LGE techniques. Image sharpness, entropy, and scar-to-blood, scar-to-myocardium, and blood-to-myocardium contrast were analyzed and reconstruction times were measured. Two expert readers assessed the image quality, ICD artifact severity, and the diagnostic confidence with scar extent. Finally, for the animal study, histopathological assessment of the heart was performed to confirm the presence and localization of scar tissue.

RESULTS

In the animal, wideband MOCO free-breathing BB-LGE were reconstructed in 0.6 s and demonstrated a 200 % improvement in scar-to-blood contrast compared to wideband breath-held PSIR-LGE, with significant improvement in image sharpness and reduction in entropy. It also effectively minimized ICD artifacts and accurately detected scars. In patients, wideband MOCO free-breathing BB-LGE were reconstructed in 1.5 ± 0.4 (standard deviation) s per slice. Seventeen patients (17/22; 77 %) with myocardial scars were confidently diagnosed with wideband MOCO free-breathing BB-LGE, compared to 11 (11/22; 50 %) with wideband breath-held PSIR-LGE (P < 0.01).

CONCLUSION

Free-breathing wideband T2-prepared black-blood LGE imaging, combined with motion-corrected reconstruction, offers a promising diagnostic approach for the evaluation of myocardial lesions in patients with ICDs.

Bacterial Communities and Their Role in Bacterial Infections

Since infections associated with microbial communities threaten human health, research is increasingly focusing on the development of biofilms and strategies to combat them. Bacterial communities may include bacteria of one or several species. Therefore, examining all the microbes and identifying individual community bacteria responsible for the infectious process is important. Rapid and accurate detection of bacterial pathogens is paramount in healthcare, food safety, and environmental monitoring. Here, we analyze biofilm composition and describe the main groups of pathogens whose presence in a microbial community leads to infection (Staphylococcus aureus, Enterococcus spp., Cutibacterium spp., bacteria of the HACEK, etc.). Particular attention is paid to bacterial communities that can lead to the development of device-associated infections, damage, and disruption of the normal functioning of medical devices, such as cardiovascular implants, biliary stents, neurological, orthopedic, urological and penile implants, etc. Special consideration is given to tissue-located bacterial biofilms in the oral cavity, lungs and lower respiratory tract, upper respiratory tract, middle ear, cardiovascular system, skeletal system, wound surface, and urogenital system. We also describe methods used to analyze the bacterial composition in biofilms, such as microbiologically testing, staining, microcolony formation, cellular and extracellular biofilm components, and other methods. Finally, we present ways to reduce the incidence of biofilm-caused infections.

Intracardiac Echocardiography-Applications in the Electrophysiology and the Cardiac Catheterization Labs

Background. Intracardiac echocardiography (ICE) is routinely used in cardiac electrophysiology and catheterization labs. It plays a vital role in understanding cardiac anatomy, procedural planning, and early identification of complications. In this review, we describe the utility of ICE for procedures in the electrophysiology lab, including atrial fibrillation ablation, left atrial appendage occlusion device implantation, and cardiac implantable electronic device (CIED) extraction. Intracardiac echocardiography also helps in the identification of complications such as pericardial effusion, pulmonary vein stenosis, and left atrial appendage thrombus. Compared with traditional echocardiographic modalities such as transesophageal echocardiogram (TEE), ICE has equivalent image quality, requires less sedation, and possesses no risk of esophageal injury. The disadvantages of ICE include a learning curve and necessity for central vascular access.

Transvenous extraction of conduction system and lumenless pacing leads

INTRODUCTION

Conduction system pacing (CSP), often accomplished with lumenless pacing leads, is increasingly employed to achieve physiologic ventricular activation. There are limited data on the extraction of these leads. The objective of this study was to describe the safety and efficacy of extraction of CSP pacing leads and compare outcomes with extraction of non-CSP lumenless leads.

METHODS

Patients undergoing CSP/non-CSP lumenless lead removal were included. Outcomes of interest included rates of complete procedural success, complications, and successful reimplantation.

RESULTS

Overall, 23 patients were included (n = 14 with CSP and n = 9 with non-CSP lumenless leads implanted in the right atrium, right ventricle, or septum). The mean age was 52.7 ± 24.0 years, 30% were female, and the mean lead age was 4.5 ± 4.4 years. The complete procedural success rate was 100%. One serious complication occurred in the non-CSP group but was unrelated to the lead of interest. Manual traction alone was successful in 57% of CSP cases (mean lead age 2.4 ± 1.7 years) and in 11% of non-CSP cases (mean lead age 7.9 ± 5.3 years). Laser sheaths were used in 43% of CSP cases and 89% of non-CSP cases; rotational cutting tools were used in no CSP cases and in 33% of non-CSP cases. Reimplantation in the conduction system was attempted with a left bundle branch pacing lead and successful in 80% (n = 4/5).

CONCLUSION

Extraction of CSP and non-CSP lumenless leads is feasible with a high success rate and a good safety profile. CSP reimplantation after extraction is also feasible with good electrical performance.

Evaluation of the Potential Targets of Shenxian-Shengmai Oral Liquid in Treating Sick Sinus Syndrome Based on Network Pharmacology and Molecular Docking

Shenxian-Shengmai (SXSM) is a Chinese patent medicine used in the treatment of sick sinus syndrome (SSS). However, its active chemical compounds and the underlying molecular mechanisms remain unclear. In this study, we researched the underlying mechanisms of SXSM in treating SSS. We conducted network analysis and molecular docking to identify the small molecules and core targets responsible for the therapeutic efficacy of SXSM on SSS. In vitro experiments were performed to verify the potential therapeutic mechanism. Network pharmacological analysis identified 17 core targets. Among these, BMP4, KCNH2, KCNMA1, and KCNQ1 were identified to be involved in various biological processes, such as the formation and regulation of the cardiac pacemaking system and potassium ion transmembrane transport. The experimental analysis revealed that SXSM could upregulate the expression of the Bmp4/Tbx3/Hcn4 pathway and the expression of Kcnh2, Kcnma1, and Kcnq1 channels, which protected and improved the pacemaking function of pacemaker cells (P cells) and increased the heart rate. These findings provide a scientific basis in the study of the mechanism of traditional Chinese medicine in the treatment of SSS.

How to Approach Patients with Cardiac Implantable Electronic Devices and Bacteremia

The approach to a patient with a cardiac implantable electronic device (CIED) and bacteremia requires a high index of suspicion. The microorganism and duration of bacteremia affect the pretest probability of CIED infection. When transesophageal echocardiography findings are equivocal, fluorodeoxyglucose-PET/computed tomography can increase the sensitivity and specificity for CIED infection. Confirmed CIED infection warrants complete system extraction. In patients with persistent gram-positive bacteremia despite antimicrobial therapy and unclear involvement of the CIED, the device is sometimes empirically extracted. Long-term effects of extraction (such as risk of suboptimal/failed cardiac resynchronization therapy reimplant) should be factored into decisions regarding empiric CIED extraction.