Infection control in implantation of cardiac implantable electronic devices: current evidence, controversial points, and unresolved issues

Prevention and Risk Assessment of Cardiac Device Infections in Clinical Practice

The implantation of cardiac electronic devices (CIEDs), including pacemakers and defibrillators, has become increasingly prevalent in recent years and has been accompanied by a significant rise in cardiac device infections (CDIs), which pose a substantial clinical and economic burden. CDIs are associated with hospitalizations and prolonged antibiotic therapy and often necessitate device removal, leading to increased morbidity, mortality, and healthcare costs worldwide. Approximately 1-2% of CIED implants are associated with infections, making this a critical issue to address. In this contemporary review, we discuss the burden of CDIs with their risk factors, healthcare costs, prevention strategies, and clinical management.

REducing INFectiOns thRough Cardiac device Envelope: insight from real world data. The REINFORCE project

AIMS

Infections resulting from cardiac implantable electronic device (CIED) implantation are severely impacting on patients' and on health care systems. The use of TYRXTM absorbable antibiotic-eluting envelope has proven to decrease major CIED infections within 12 months of CIED surgery. The aim is to evaluate the impact of the envelope use on infection-related clinical events in a real-world contemporary patient population.

METHODS AND RESULTS

Data on patients undergoing CIED surgery were collected prospectively by participating centers of the One Hospital ClinicalService project. Patients were divided into two groups according to whether TYRXTM absorbable antibiotic-eluting envelope was used or not. Out of 1819 patients, 872 (47.9%) were implanted with an absorbable antibiotic-eluting envelope and included in the Envelope group and 947 (52.1%) patients who did not receive an envelope were included in the Control group. Compared to control, patients in the Envelope group had higher thrombo-embolic or hemorrhagic risk, higher BMI, lower LVEF and more comorbidities. During a mean follow-up of 1.4 years, the incidence of infection-related events was significantly higher in the control compared to the Envelope group (2.4% vs. 0.8%, P = 0.007). The five-year cumulative incidence of infection-related events was 8.1% in the control and 2.1% in the Envelope group (HR: 0.34, 95%CI: 0.14-0.80, P = 0.010).

CONCLUSION

In our analysis, the use of an absorbable antibiotic-eluting envelope in the general CIED population was associated with a lower risk of systemic and pocket infection.

Cardiac Implantable Electronic Devices Infection Assessment, Diagnosis and Management: A Review of the Literature

The use of increasingly complex cardiac implantable electronic devices (CIEDs) has increased exponentially in recent years. One of the most serious complications in terms of mortality, morbidity and financial burden is represented by infections involving these devices. They may affect only the generator pocket or be generalised with lead-related endocarditis. Modifiable and non-modifiable risk factors have been identified and they can be associated with patient or procedure characteristics or with the type of CIED. Pocket and systemic infections require a precise evaluation and a specialised treatment which in most cases involves the removal of all the components of the device and a personalised antimicrobial therapy. CIED retention is usually limited to cases where infection is unlikely or is limited to the skin incision site. Optimal re-implantation timing depends on the type of infection and on the results of microbiological tests. Preventive strategies, in the end, include antibiotic prophylaxis before CIED implantation, the possibility to use antibacterial envelopes and the prevention of hematomas. The aim of this review is to investigate the pathogenesis, stratification, diagnostic tools and management of CIED infections.

Risk Factors for Mortality in Cardiac Implantable Electronic Device (CIED) Infections: A Systematic Review and Meta-Analysis

Background: Infections following cardiac implantable electronic device (CIED) implantation can require surgical device removal and often results in significant cost, morbidity, and potentially mortality. We aimed to systemically review the literature and identify risk factors associated with mortality following CIED infection. Methods: Electronic searches (up to June 2021) were performed on PubMed and Scopus. Twelve studies (10 retrospective, 2 prospective cohort studies) were included for analysis. Meta-analysis was conducted with the restricted maximum likelihood method, with mortality as the outcome. The overall mortality was 13.7% (438/1398) following CIED infection. Results: On meta-analysis, the male sex (OR 0.77, 95%CI 0.57–1.01, I² = 2.2%) appeared to have lower odds for mortality, while diabetes mellitus appeared to be associated with higher mortality (OR 1.47, 95%CI 0.67–3.26, I² = 81.4%), although these trends did not reach statistical significance. Staphylococcus aureus as the causative organism (OR 2.71, 95%CI 1.76–4.19, I² = 0.0%), presence of heart failure (OR 1.92, 95%CI 1.42–4.19, I² = 0.0%) and embolic phenomena (OR 4.00, 95%CI 1.67–9.56, I² = 69.8%) were associated with higher mortality. Surgical removal of CIED was associated with lower mortality compared with conservative management with antibiotics alone (OR 0.22, 95%CI 0.09–0.50, I² = 62.8%). Conclusion: We identified important risk factors associated with mortality in CIED infections, including Staphyloccocus aureus as the causative organism, and the presence of complications, such as heart failure and embolic phenomena. Surgery, where possible, was associated with better outcomes.

Impact of Choice of Prophylaxis on the Microbiology of Cardiac Implantable Electronic Device Infections: Insights From the Prevention of Arrhythmia Device Infection Trial (PADIT)

Background

The Prevention of Arrhythmia Device Infection Trial (PADIT) investigated whether intensification of perioperative prophylaxis could prevent cardiac implantable electronic device (CIED) infections. Compared with a single dose of cefazolin, the perioperative administration of cefazolin, vancomycin, bacitracin, and cephalexin did not significantly decrease the risk of infection. Our objective was to compare the microbiology of infections between study arms in PADIT.

Methods

This was a post hoc analysis. Differences between study arms in the microbiology of infections were assessed at the level of individual patients and at the level of microorganisms using the Fisher exact test.

Results

Overall, 209 microorganisms were reported from 177 patients. The most common microorganisms were coagulase-negative staphylococci (CoNS; 82/209 [39.2%]) and S. aureus (75/209 [35.9%]). There was a significantly lower proportion of CoNS in the incremental arm compared with the standard arm (30.1% vs 46.6%; P = .04). However, there was no significant difference between study arms in the frequency of recovery of other microorganisms. In terms of antimicrobial susceptibility, 26.5% of microorganisms were resistant to cefazolin. CoNS were more likely to be cefazolin-resistant in the incremental arm (52.2% vs 26.8%, respectively; P = .05). However, there was no difference between study arms in terms of infections in which the main pathogen was sensitive to cefazolin (77.8% vs 64.3%; P = .10) or vancomycin (90.8% vs 90.2%; P = .90).

Conclusions

Intensification of the prophylaxis led to significant changes in the microbiology of infections, despite the absence of a decrease in the overall risk of infections. These findings provide important insight on the physiopathology of CIED infections.

Trial registration

NCT01002911.

Atypical pathogens associated with cardiac implantable electronic device infections

BACKGROUND

Cardiovascular implantable electronic device (CIED) infections are associated with significant morbidity and mortality making the identification of the causative organism critical. The vast majority of CIED infections are caused by Staphylococcal species. CIED infections associated with atypical pathogens are rare and have not been systematically investigated. The objective of this study is to characterize the clinical course, management and outcome in patients with CIED infection secondary to atypical pathogens.

METHODS

Medical records of all patients who underwent CIED system extraction at the University of Chicago Medical Center between January 2010 and November 2020 were retrospectively reviewed to identify patients with CIED infection. Demographic, clinical, infection-related and outcome data were collected. CIED infections were divided into typical and atypical groups based on the pathogens isolated.

RESULTS

Among 356 CIED extraction procedures, 130 (37%) were performed for CIED infection. Atypical pathogens were found in 5.4% (n = 7) and included Pantoea species (n = 2), Kocuria species (n = 1), Cutibacterium acnes (n = 1), Corynebacterium tuberculostearicum (n = 1), Corynebacterium striatum (n = 1), Stenotrophomonas maltophilia (n = 1), and Pseudozyma ahidis (n = 1). All patients with atypical CIED infections were successfully treated with total system removal and tailored antibiotic therapy. There were no infection-related deaths.

CONCLUSIONS

CIED infections with atypical pathogens were rare and associated with good outcome if diagnosed early and treated with total system removal and tailored antimicrobial therapy. Atypical pathogens cultured from blood, tissue or hardware in patients with CIED infection should be considered pathogens and not contaminants.

Patient Profiles in the Utilization of the CanGaroo® Envelope

Background The CanGaroo® Envelope (Aziyo Biologics, Silver Spring, MD) is intended to securely hold a cardiovascular implantable electronic device (CIED) to create a stable environment when implanted in the body. Data on the utilization of this newly available product are limited. Objective In this study, our objective was to describe the specific profiles of patients who may benefit from the use of the CanGaroo® Envelope at the time of CIED implantation. Methods  The utilization of the CanGaroo® Envelope was assessed from January 2019 to October 2019 among a series of patients who were either undergoing de-novo CIED implantation or replacement. Results Among a total of 50 patients, the CanGaroo® Envelope was utilized in 15 (30%). Three distinct patient profiles were identified: profile 1: elderly patients with poor tissue turgor at risk of wound dehiscence or erosion; profile 2: patients with a history of previous device infection; and profile 3: patients at high risk of device infection having one or more of the following risk factors - chronic kidney disease, immunocompromised state, or diabetes mellitus. At a mean follow-up of 18 ±3 months, no CIED pocket erosion, dehiscence, or infection was noted. Conclusions Three distinct profiles of patients who could potentially benefit from the use of the CanGaroo® Envelope were identified by the implanting physicians. Long-term follow-up data, including infection and wound dehiscence rates, are necessary to further analyze the optimal utilization of the device.

Transvenous extraction of permanent pacemaker and defibrillator leads: Reduced procedural complexity and higher procedural success rates in patients with infective versus noninfective indications

INTRODUCTION

Transvenous lead extraction (TLE) is critical in the long-term management of patients with cardiac implanted electronic devices (CIEDs). The aim of the study is to evaluate the outcomes of TLE and to investigate the impact of infection.

METHODS AND RESULTS

Data of patients undergoing extraction of permanent pacemaker and defibrillator leads during October 2014-September 2019 were prospectively analyzed. Overall, 242 consecutive patients (aged 71.0 ± 14.0 years, 31.4% female), underwent an equal number of TLE operations for the removal of 516 leads. Infection was the commonest indication (n = 201, 83.1%). Mean implant-to-extraction duration was 7.6 ± 5.4 years. Complete procedural success was recorded in 96.1%, and clinical procedural success was achieved in 97.1% of attempted lead extractions. Major complications occurred in two (0.8%) and minor complications in seven (2.9%) patients. Leads were removed exclusively by using locking stylets in 65.7% of the cases. In the subgroup of noninfective patients, advanced extraction tools were more frequently required compared to patients with CIED infections, to extract leads (success only with locking stylet: 55.8% vs. 67.8%, p = .032). In addition, patients without infection demonstrated lower complete procedural success rates (90.7% vs. 97.2%, p = .004), higher major complication rates (2.4% vs. 0.5%, p = .31) and longer procedural times (136 ± 13 vs. 111 ± 15 min, p = .001).

CONCLUSIONS

Our data demonstrate high procedural efficacy and safety and indicate that in patients with noninfective indications, the procedure is more demanding, thus supporting the hypothesis that leads infection dissolves and/or prohibits the formation of fibrotic adherences.

Endovascular Neuromodulation: Safety Profile and Future Directions

Endovascular neuromodulation is an emerging technology that represents a synthesis between interventional neurology and neural engineering. The prototypical endovascular neural interface is the Stentrode^TM, a stent-electrode array which can be implanted into the superior sagittal sinus via percutaneous catheter venography, and transmits signals through a transvenous lead to a receiver located subcutaneously in the chest. Whilst the Stentrode^TM has been conceptually validated in ovine models, questions remain about the long term viability and safety of this device in human recipients. Although technical precedence for venous sinus stenting already exists in the setting of idiopathic intracranial hypertension, long term implantation of a lead within the intracranial veins has never been previously achieved. Contrastingly, transvenous leads have been successfully employed for decades in the setting of implantable cardiac pacemakers and defibrillators. In the current absence of human data on the Stentrode^TM, the literature on these structurally comparable devices provides valuable lessons that can be translated to the setting of endovascular neuromodulation. This review will explore this literature in order to understand the potential risks of the Stentrode^TM and define avenues where further research and development are necessary in order to optimize this device for human application.

Postoperative Antibiotic Prophylaxis Following Cardiac Implantable Electronic Device Placement

Infections related to cardiac implantable electronic device (CIED) placement are associated with poor clinical outcomes. As such, preprocedural prophylactic antibiotic therapy is indicated for all patients prior to device insertion. However, the available data are less clear on the impact of postprocedural antibiotic therapy on rates of CIED infection when used in addition to preprocedural therapy. This is single-center, retrospective cohort study of 913 patients who underwent CIED-related procedures between October 2010 and August 2014 sought to compare the rate of CIED infections in patients receiving only preprocedural antibiotics with those receiving both preprocedural and postprocedural antibiotics. Univariate analysis was used to detect independent risk factors for CIED infection. After excluding patients receiving concomitant antibiotics for other conditions, those undergoing CIED extraction alone, and those with a lack of follow-up data and/or adequate documentation of clinical encounters, 569 patients were identified for inclusion in the final analysis. The majority of patients who received postprocedural antibiotics received three to five days of therapy, with the most common antibiotic used being cephalexin. There was no statistically significant difference in the incidence of infection between patients who did and did not receive postoperative antibiotics (4.5% versus 6.1%; p = 0.398). In a multivariate analysis, the use of postprocedural antibiotic therapy was not a significant risk factor for infection (adjusted odds ratio: 0.692; 95% confidence interval: 0.314–1.525; p = 0.361). It is therefore reasonable to withhold prescribing postoperative antibiotics in patients following CIED implantation. Individualized risk factor evaluation of patient comorbidities and procedural characteristics may be needed to aid in determining whether postoperative antibiotics are reasonable in different patients. The validity of these findings is contingent on further confirmation via a prospective, randomized clinical trial.

Prevalence of major complications and procedural mortality in 336 dogs undergoing interventional cardiology procedures in a single academic center

INTRODUCTION

Overall complication rates associated with a wide range of diagnostic and therapeutic interventional cardiac procedures in a contemporary academic setting have not been reported.

ANIMALS, MATERIALS AND METHODS

Consecutive interventional procedures performed for client-owned dogs were retrospectively analyzed to characterize procedural complications and mortality.

RESULTS

Three hundred sixty-four procedures were performed on 336 dogs. Interventions included attempted or completed transvenous pacemaker (PM) implantation (n = 134) with subsequent pacing system revision (n = 8), pulmonic balloon valvuloplasty (BVP) (n = 117) with a subset of patients undergoing an additional BVP (n = 14), transarterial closure of left-to-right shunting patent ductus arteriosus (PDA) (n = 66), diagnostic angiography and/or cardiovascular pressure measurement (n = 9), transvenous temporary pacing (n = 7), septal defect occlusion (n = 5), heartworm extraction (n = 3), and BVP catheter fragment retrieval (n = 1). The prevalence of major perioperative and postoperative complications for all procedures was 5% and 6%, respectively, and the procedural mortality rate was 2%. The overall rate of major complications was 12% for the PM group, 11% for the BVP group, and 2% for the PDA occlusion group. Both PM implantation and BVP have higher rates of major complications overall compared with PDA occlusion (p=0.0151).

CONCLUSIONS

The results of this study indicate that the prevalence of major complications and mortality associated with interventional cardiac procedures is low; however, significant differences exist in complication rates between procedures.

Comparison of epicardial vs. endocardial reimplantation in pacemaker-dependent patients with device infection

Aims

Reimplantation of cardiac implantable electronic devices (CIEDs) after extraction due to device infection is a major issue in pacemaker-dependent patients. We compared in-hospital and long-term outcomes with two techniques: epicardial reimplantation (EPI) before CIED extraction and temporary pacing (TP) with a view to delayed endocardial reimplantation.

Methods and results

Two cohorts of consecutive pacemaker-dependent patients who underwent transvenous lead extraction at our tertiary centre were included in this retrospective cohort study. According to successive policies, either the EPI or the TP approach was used. In-hospital complications occurred at similar rates in the EPI (n = 59) and TP (n = 52) cohorts (37.3% vs. 32.7%, respectively; P = 0.61). Thirteen (25.0%) patients in the TP cohort eventually were reimplanted epicardially, mainly because of infection of the temporary lead. Finally, 65 patients were discharged with an epicardial device and 37 with an endocardial device. Median follow-up was 41.7 (interquartile range 34.1-51.5) months. No difference was observed in long-term mortality according to the reimplantation strategy, but use of TP was associated with a reduced risk of late endocarditis and device reintervention (hazard ratio (HR) 0.25, 95% confidence interval (CI) 0.09-0.069, P = 0.01), whereas epicardial device reimplantation was associated with an increased risk (HR 3.62, 95% CI 1.07-12.21, P = 0.04).

Conclusion

We observed similar in-hospital outcomes in our EPI and TP cohorts. Twenty-five percent of the patients initially paced by a TP strategy finally needed an epicardial device, mainly because of infection of their TP lead. Use of TP resulted in lower rates of late endocarditis and device reintervention.

Latex and a ZnO-based multi-functional material for cardiac implant-related inflammation

A new memory latex foam with ZnO modification was developed to reduce the incidence of both bacteria- and shaking-induced pocket inflammation.

Infective endocarditis and risk of death after cardiac implantable electronic device implantation: a nationwide cohort study

Aims

To determine the incidence, risk factors, and mortality of infective endocarditis (IE) following implantation of a first-time, permanent, cardiac implantable electronic device (CIED).

Methods and results

From Danish nationwide administrative registers (beginning in 1996), we identified all de-novo permanent pacemakers (PMs) and implantable cardioverter defibrillators (ICDs) together with the occurrence of post-implantation IE-events in the period from 2000-2012. Included were 43 048 first-time PM/ICD recipients. Total follow-up time was 168 343 person-years (PYs). The incidence rate (per 1000 PYs) of IE in PM was 2.1 (95% confidence interval [CI]: 1.7-2.6) for single chamber devices and 6.2 (95% CI: 4.5-8.7) for cardiac resynchronization therapy (CRT); similarly, the rate of IE in ICD was 3.7 (95% CI: 2.9-4.7) in single chamber devices and 6.3 (95% CI: 4.4-9.0) in CRT. In multivariable analysis, increased PM complexity served as independent risk factor for IE {dual chamber PM [hazard ratio (HR) 1.39; 95% CI: 1.07-1.80] and CRT [HR: 1.84; 95% CI: 1.20-2.84]}. During follow-up, generator replacement (HR: 2.79; 95% CI: 1.87-4.17) and lead revision (HR: 4.33; 95% CI: 3.25-5.78) in PMs were associated with increased risk. Corresponding estimates in ICDs were 2.49 (95% CI: 1.28-4.86) and 6.58 (95% CI: 4.49-9.63). Risk of death after IE was significantly increased in PM and ICD with HRs of 1.56 (95% CI: 1.33-1.82) and 2.63 (95% CI: 2.00-3.48), respectively.

Conclusion

The risk of IE increased with increasing PM complexity. Other important risk factors were subsequent generator replacement and lead revision. IE was associated with an increased risk of mortality in the area of CIED.

Skin lesions over the pocket area that may mimic cardiac implantable electronic device infection: A case series

BACKGROUND

The early and correct diagnosis of cardiac implantable electronic device (CIED) infections is critical given that early aggressive treatment with complete removal of the system along with antimicrobial therapy dramatically improves outcomes. Pocket infection manifested by local signs of inflammation is the most common form of CIED infections. Conditions mimicking pocket infection have been described in the literature. These include various types of malignancy and rarely allergic reactions/contact dermatitis to pacemaker compounds. We aimed to describe skin lesions and disorders over the pocket area that mimic CIED infection.

METHODS

We present a series of five cases with skin lesions that mimic pocket infection. We document these cases with corresponding photographs. Most of them have not been described in this setting.

RESULTS

We report the following cases of conditions that proved not to be CIED infection: One case of superficial cellulitis, one case of herpes zoster over the pocket area, one case of spontaneous bruising over the pocket a long time after implantation in a patient taking oral anticoagulation, and two cases of contact dermatitis due to prolonged postoperative application of povidone-iodine. All cases had favorable outcome after conservative treatment and no CIED infection was developed during follow-up.

CONCLUSION

Clinicians should be aware of rare conditions that mimic CIED infection. Incorrect diagnosis of these disorders may falsely lead to CIED extraction.

Prevenção da formação de biofilmes em marcapassos artificiais: é viável?

Resumo Objetivo: Identificar os agentes antimicrobianos utilizados na prevenção da formação de biofilme em marcapassos artificiais. Métodos: Revisão da literatura para responder a seguinte questão: “Quais agentes antimicrobianos são usados para prevenir a formação de biofilmes em marcapassos artificiais?” As bases de dados PubMed, Web of Science, Scopus, Science Direct, Cochrane, CINAHL, Embase e LILACS foram consultadas em todos os idiomas sem restrição de tempo. Resultados: A amostra final apresentou cinco estudos primários, sendo a maioria experimental. As investigações identificaram agentes com potencial para a redução ou inibição da formação de biofilmes em marcapassos. Destacou-se a associação de agentes físico-químicos e farmacológicos aos agentes antimicrobianos. Conclusão: A prevenção da formação de biofilmes em marcapassos é viável. Os agentes mais promissores para obter este efeito foram a rifampicina, AIGIS®, a formulação aquosa neobactrim e a cobertura com trimetilsilano e oxigênio em superfícies tratadas com plasma.

Prevention, Diagnosis, and Treatment of Cardiac Implantable Electronic Device Infections

Cardiac implantable electronic device (CIED) infections are complex medical problems that are increasingly encountered. They are associated with significant morbidity and mortality with tremendous economic cost. The current review will emphasize the prevention, diagnosis, and treatment of this clinical entity using the relatively limited evidence that is currently available. Because there is a paucity of high quality evidence regarding prevention, diagnosis, and treatment of CIED infections, this review will attempt to summarize the best evidence as well as to suggest, when possible, paradigms for care. The topic of CIED infections is a dynamic one as the scope of CIED continues to widen. Furthermore, there are promising advancements in CIED technology which may help reduce its occurrence the future. Unfortunately, significant gaps in knowledge remain, and definitive recommendations regarding CIED infections and future studies should be directed at improving our ability to prevent infections.

Implantable cardioverter defibrillator management: an update

Implantable cardioverter defibrillator (ICD) is the cornerstone of primary and secondary prevention of sudden cardiac death. In 35 years of technologic improvement and clinical trials, there has been a continuous increase in implantation rate. Purpose of this review is to point out and discuss every aspect related to actual ICD management, investigating implantation procedure and predischarge care, office and remote monitoring follow-up, diagnostic evaluations, management of patients with suspected therapies or malfunctions, heart failure, surgery, radiotherapy and endoscopic procedures. Also, ICD backface such as infections and other complications will be discussed. Finally, we will focus on interesting future perspectives for this setting of patients.