Efficacy of a Bio-Absorbable Antibacterial Envelope to Prevent Cardiac Implantable Electronic Device Infections in High-Risk Subjects

Cardiovascular Implantable Electronic Device Infections: A Contemporary Review

Infections associated with cardiac implantable electronic devices (CIEDs) are increasing and are a cause of significant morbidity and mortality. This article summarizes the latest updates with respect to the epidemiology, microbiology, and risk factors for CIED-related infections. It also covers important considerations regarding the diagnosis, management, and prevention of these infections. Newer technologies such as leadless pacemakers and subcutaneous implantable cardioverters and defibrillators are discussed.

The Neurostimulation Appropriateness Consensus Committee (NACC)®: Recommendations for the Mitigation of Complications of Neurostimulation

INTRODUCTION

The International Neuromodulation Society convened a multispecialty group of physicians based on expertise and international representation to establish evidence-based guidance on the mitigation of neuromodulation complications. This Neurostimulation Appropriateness Consensus Committee (NACC)® project intends to update evidence-based guidance and offer expert opinion that will improve efficacy and safety.

MATERIALS AND METHODS

Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from 2017 (when NACC last published guidelines) to October 2023. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on the strength of evidence or consensus when evidence was scant.

RESULTS

The NACC examined the published literature and established evidence- and consensus-based recommendations to guide best practices. Additional guidance will occur as new evidence is developed in future iterations of this process.

CONCLUSIONS

The NACC recommends best practices regarding the mitigation of complications associated with neurostimulation to improve safety and efficacy. The evidence- and consensus-based recommendations should be used as a guide to assist decision-making when clinically appropriate.

Citric Acid: A Nexus Between Cellular Mechanisms and Biomaterial Innovations

Citrate-based biodegradable polymers have emerged as a distinctive biomaterial platform with tremendous potential for diverse medical applications. By harnessing their versatile chemistry, these polymers exhibit a wide range of material and bioactive properties, enabling them to regulate cell metabolism and stem cell differentiation through energy metabolism, metabonegenesis, angiogenesis, and immunomodulation. Moreover, the recent US Food and Drug Administration (FDA) clearance of the biodegradable poly(octamethylene citrate) (POC)/hydroxyapatite-based orthopedic fixation devices represents a translational research milestone for biomaterial science. POC joins a short list of biodegradable synthetic polymers that have ever been authorized by the FDA for use in humans. The clinical success of POC has sparked enthusiasm and accelerated the development of next-generation citrate-based biomaterials. This review presents a comprehensive, forward-thinking discussion on the pivotal role of citrate chemistry and metabolism in various tissue regeneration and on the development of functional citrate-based metabotissugenic biomaterials for regenerative engineering applications.

Use of an Antibacterial Envelope in Spinal Cord Stimulation Reduces the Rate and Severity of Iatrogenic Infections

OBJECTIVE

To examine if the use of an antibacterial envelope (TYRX) decreases the rate of postoperative infection in chronic pain patients undergoing treatment with spinal cord stimulation (SCS) involving device implantation.

METHODS

Single-center retrospective cohort study comparing postoperative infections rates in non-TYRX recipients from 2018 to 2020 with recipients of a TYRX antibacterial envelope from 2020 to 2021. Infection was registered if a patient received any form of antibiotic treatment after hospital discharge within a follow-up period of 100 days.

RESULTS

A total of 198 patients were included: 100 in the TYRX group and 98 in the non-TYRX group. There were no significant differences between the 2 groups regarding age, body mass index (BMI), smoking, diabetes, and use of immunosuppression. The overall infection rate was 5.6%. The infection rate was 4% in the TYRX group and 7.1% in the non-TYRX group (P = 0.6). However, the 4 cases of postoperative infection in the TYRX group could be effectively managed with oral antibiotics alone, whereas 6 out of the 7 patients in the non-TYRX group required intravenous antibiotics. Moreover, device explantation was necessary in 3 of these patients suggesting the event of more severe infections in the non-TYRX group (P = 0.014).

CONCLUSIONS

The TYRX antibacterial envelope displayed infection rates reducing capabilities, along with a clear tendency to reduce revision surgeries and system removals due to infections.

The BLISTER Score: A Novel, Externally Validated Tool for Predicting Cardiac Implantable Electronic Device Infections, and Its Cost-Utility Implications for Antimicrobial Envelope Use

BACKGROUND

Antimicrobial envelopes reduce the incidence of cardiac implantable electronic device infections, but their cost restricts routine use in the United Kingdom. Risk scoring could help to identify which patients would most benefit from this technology.

METHODS

A novel risk score (BLISTER [Blood results, Long procedure time, Immunosuppressed, Sixty years old (or younger), Type of procedure, Early re-intervention, Repeat procedure]) was derived from multivariate analysis of factors associated with cardiac implantable electronic device infection. Diagnostic utility was assessed against the existing PADIT score (Prior procedure, Age, Depressed renal function, Immunocompromised, Type of procedure) in both standard and high-risk external validation cohorts, and cost-utility models examined different BLISTER and PADIT score thresholds for TYRX (Medtronic; Minneapolis, MN) antimicrobial envelope allocation.

RESULTS

In a derivation cohort (n=7383), cardiac implantable electronic device infection occurred in 59 individuals within 12 months of a procedure (event rate, 0.8%). In addition to the PADIT score constituents, lead extraction (hazard ratio, 3.3 [95% CI, 1.9-6.1]; P<0.0001), C-reactive protein >50 mg/L (hazard ratio, 3.0 [95% CI, 1.4-6.4]; P=0.005), reintervention within 2 years (hazard ratio, 10.1 [95% CI, 5.6-17.9]; P<0.0001), and top-quartile procedure duration (hazard ratio, 2.6 [95% CI, 1.6-4.1]; P=0.001) were independent predictors of infection. The BLISTER score demonstrated superior discriminative performance versus PADIT in the standard risk (n=2854, event rate: 0.8%, area under the curve, 0.82 versus 0.71; P=0.001) and high-risk validation cohorts (n=1961, event rate: 2.0%, area under the curve, 0.77 versus 0.69; P=0.001), and in all patients (n=12 198, event rate: 1%, area under the curve, 0.8 versus 0.75, P=0.002). In decision-analytic modeling, the optimum scenario assigned antimicrobial envelopes to patients with BLISTER scores ≥6 (10.8%), delivering a significant reduction in infections (relative risk reduction, 30%; P=0.036) within the National Institute for Health and Care Excellence cost-utility thresholds (incremental cost-effectiveness ratio, £18 446).

CONCLUSIONS

The BLISTER score (https://qxmd.com/calculate/calculator_876/the-blister-score-for-cied-infection) was a valid predictor of cardiac implantable electronic device infection, and could facilitate cost-effective antimicrobial envelope allocation to high-risk patients.

Enabling Proregenerative Medical Devices via Citrate-Based Biomaterials: Transitioning from Inert to Regenerative Biomaterials

Regenerative medicine aims to restore tissue and organ function without the use of prosthetics and permanent implants. However, achieving this goal has been elusive, and the field remains mostly an academic discipline with few products widely used in clinical practice. From a materials science perspective, barriers include the lack of proregenerative biomaterials, a complex regulatory process to demonstrate safety and efficacy, and user adoption challenges. Although biomaterials, particularly biodegradable polymers, can play a major role in regenerative medicine, their suboptimal mechanical and degradation properties often limit their use, and they do not support inherent biological processes that facilitate tissue regeneration. As of 2020, nine synthetic biodegradable polymers used in medical devices are cleared or approved for use in the United States of America. Despite the limitations in the design, production, and marketing of these devices, this small number of biodegradable polymers has dominated the resorbable medical device market for the past 50 years. This perspective will review the history and applications of biodegradable polymers used in medical devices, highlight the need and requirements for regenerative biomaterials, and discuss the path behind the recent successful introduction of citrate-based biomaterials for manufacturing innovative medical products aimed at improving the outcome of musculoskeletal surgeries.

Preclinical evaluation of a third-generation absorbable antibacterial envelope

BACKGROUND

The TYRX (Medtronic) absorbable antibacterial envelope has been shown to stabilize implantable cardiac devices and reduce infection. A third-generation envelope was developed to reduce surface roughness with a redesigned multifilament mesh and enhanced form factor but identical polymer coating and antibiotic concentrations as the currently available second-generation envelope.

OBJECTIVE

The purpose of this study was to compare drug elution, bacterial challenge efficacy, stabilization, and absorption of second- vs third-generation envelopes.

METHODS

Antibiotic elution was assessed in vitro and in vivo. For efficacy against gram-positive/gram-negative bacteria, 40 rabbits underwent device insertions with or without third-generation envelopes. For stabilization (migration, rotation), 5 sheep were implanted with 6 devices each in second- or third-generation envelopes. Prespecified acceptance criteria were <83-mm migration and <90° rotation. Absorption was assessed via gross pathology.

RESULTS

Elution curves were equivalent (similarity factors ≥50 per Food and Drug Administration guidance). Third-generation envelopes eluted antibiotics above minimal inhibitory concentration (MIC) in vivo at 2 hours postimplant through 7 days, consistent with second-generation envelopes. Bacterial challenge showed reductions (P <.05) in infection with second- and third-generation envelopes. Device migration was 5.5 ± 3.5 mm (third-generation) vs 9. 9 ±7.9 mm (second-generation) (P <.05). Device rotation was 18.9° ± 11.4° (third-generation) vs 17.6° ± 15.1° (second-generation) and did not differ (P = .79). Gross pathology confirmed the absence of luminal mesh remainders and no differences in peridevice fibrosis at 9 or 12 weeks.

CONCLUSION

The third-generation TYRX absorbable antibacterial envelope demonstrated equivalent preclinical performance to the second-generation envelope. Antibiotic elution curves were similar, elution was above MIC for 7 days, infections were reduced compared to no envelope, and acceptance criteria for migration, rotation, and absorption were met.

Physician antibiotic hydration preferences for biologic antibacterial envelopes during cardiac implantable device procedures

Background

Cardiac implantable electronic device (CIED) infection is a potentially serious complication of CIED procedures. Infection risk mitigation includes using guideline-recommended pre-operative intravenous antibacterial prophylaxis (IV ABX). The use of antibiotic-eluting CIED envelopes has also been shown to reduce infection risk. The relationship between and potential benefits associated with guideline-recommended IV ABX in combination with antibacterial envelopes have not been characterized.

Methods

Biologic envelopes made from non-crosslinked extracellular matrix (ECM) were implanted into 1,102 patients receiving CIEDs. The implanting physician decided patient selection for using a biologic envelope and envelope hydration solution. Observational data was analyzed on IV ABX utilization rates, antibacterial envelope usage, and infection outcomes.

Results

Overall compliance with IV ABX was 96.6%, and most patients received a biologic envelope hydrated in antibiotics (77.1%). After a mean follow-up of 223 days, infection rates were higher for sites using IV ABX <80% of the time vs. sites using ≥80% (5.6% vs. 0.8%, p = 0.008). Physicians demonstrated preference for hydration solutions containing gentamicin in higher-risk patients, which was found by multivariate analysis to be associated with a threefold reduction in infection risk (OR 3.0, 95% CI, 1.0-10.0).

Conclusion

These findings suggest that use of antibiotics, particularly gentamicin, in biologic envelope hydration solution may reduce infection risk, and use of antibacterial envelopes without adjunct IV ABX may not be sufficient to reduce CIED infections.

Clinical trial registration

[https://clinicaltrials.gov/], identifier [NCT02530970].

Risk Scores for Cardiac Implantable Electronic Device Infection: Which One to Believe In?

Infections are important complications of cardiac implantable electronic devices (CIED), with a high prognostic impact. Several risk factors for CIED infections are known. Different studies have been published proposing different risk scores, in order to preoperatively assess the individual likelihood of developing a CIED infection. Among the different scores, large heterogeneity exists and there is no consensus or convergence on a single score finding large applicability in global practice. The aim of this review is to comprehensively present and analyze all the available risk scores for CIED infection, with particular regard to the evidence of comparison studies.

Deep brain stimulation for phantom limb pain

Phantom limb pain is a rare cause of chronic pain in children but it is associated with extremely refractory pain and disability. The reason for limb amputation is often due to treatment for cancer or trauma and it has a lower incidence compared to adults. The mechanism of why phantom pain exists remains uncertain and may be a result of cortical reorganisation as well as ectopic peripheral input. Treatment is aimed at reducing both symptoms as well as managing pain related disability and functional restoration. Neuromodulatory approaches using deep brain stimulation for phantom limb pain is reserved for only the most refractory cases. The targets for brain stimulation include the thalamic nuclei and motor cortex. Novel targets such as the anterior cingulate cortex remain experimental as cases of serious adverse effects such as seziures have limited their widespread uptake. A multidisciplinary approach is crucial to successful rehabilitation using a biopsychosocial pain management approach.

Antibiotic-Eluting Envelopes for the Prevention of Cardiac Implantable Electronic Device Infections: Rationale, Efficacy, and Cost-Effectiveness

Infections related to cardiac implantable electronic devices (CIED) are associated with significant morbidity and mortality. Despite optimal use of antimicrobials and other preventive strategies, the incidence of CIED infections is increasing over time leading to considerable costs to the healthcare systems. Recently, antibiotic-eluting envelopes (AEEs) have been introduced as a promising technology to prevent CIED infections. This review will address the current evidence on stratification of CIED infection risk, present the rationale behind AEE, and summarize the currently available evidence for CIED infection prevention as well as demonstrate the cost-effectiveness of this novel technology.

Incidence and Predictors of Infections and All-Cause Death in Patients with Cardiac Implantable Electronic Devices: The Italian Nationwide RI-AIAC Registry

BACKGROUND

The incidence of infections associated with cardiac implantable electronic devices (CIEDs) and patient outcomes are not fully known.

AIM

To provide a contemporary assessment of the risk of CIEDs infection and associated clinical outcomes.

METHODS

In Italy, 18 centres enrolled all consecutive patients undergoing a CIED procedure and entered a 12-months follow-up. CIED infections, as well as a composite clinical event of infection or all-cause death were recorded.

RESULTS

A total of 2675 patients (64.3% male, age 78 (70-84)) were enrolled. During follow up 28 (1.1%) CIED infections and 132 (5%) deaths, with 152 (5.7%) composite clinical events were observed. At a multivariate analysis, the type of procedure (revision/upgrading/reimplantation) (OR: 4.08, 95% CI: 1.38-12.08) and diabetes (OR: 2.22, 95% CI: 1.02-4.84) were found as main clinical factors associated to CIED infection. Both the PADIT score and the RI-AIAC Infection score were significantly associated with CIED infections, with the RI-AIAC infection score showing the strongest association (OR: 2.38, 95% CI: 1.60-3.55 for each point), with a c-index = 0.64 (0.52-0.75), p = 0.015. Regarding the occurrence of composite clinical events, the Kolek score, the Shariff score and the RI-AIAC Event score all predicted the outcome, with an AUC for the RI-AIAC Event score equal to 0.67 (0.63-0.71) p < 0.001.

CONCLUSIONS

In this Italian nationwide cohort of patients, while the incidence of CIED infections was substantially low, the rate of the composite clinical outcome of infection or all-cause death was quite high and associated with several clinical factors depicting a more impaired clinical status.

Cardiovascular implantable electronic devices in hemodialysis patients: an updated review

Cardiovascular diseases are the leading life-threatening complications in hemodialysis patients. In this scenario, both tachy-arrhythmias and brady-arrhythmias are involved with related hemodialysis and nonhemodialysis-dependent mechanisms; moreover, those arrhythmias usually occur in different time intervals before sudden cardiac death (SCD). Furthermore, current evidence shows that the presence of advanced chronic kidney disease (CKD) reduces the benefits of implantable cardioverter--defibrillators (ICDs), which increases the risk of both arrhythmic and nonarrhythmic death, especially in patients with advanced stages of heart failure. Notably, patients with advanced CKD show a more severe degree of heart failure compared with mild CKD patients. However, the benefits of the ICD implantation in the primary prevention of hemodialysis patients is still controversial, and by now, no significant benefits have emerged compared with nonhemodialysis-dependent CKD patients. In secondary prevention, hemodialysis patients with ICD implantation have higher mortality rates compared with nonhemodialysis-dependent CKD patients with ICD. On the other hand, most articles include hemodialysis patients with reduced left ventricular ejection fraction, neglecting those with preserved systolic function. This review focuses on the epidemiology of SCD in the setting of hemodialysis and the current evidence on ICD implantation in patients on hemodialysis therapy analyzing novel strategies, which might reduce the risk of ICD placing.

Burden of disease and costs of infections associated with cardiac implantable electronic devices

INTRODUCTION

Infections are complications of Cardiac Implantable Electronic Device (CIED) procedures, associated with high mortality (20-25% at 1 year), long hospitalizations (23-30 days), and high costs for health-care systems (often higher than 30.000 €). The incidence rates are around 1-4%. Prevention strategies appear to be the best approach for minimizing the occurrence of CIED infections, but in real-world, the recommendations for the best practices are not always followed. Among the recommended preventive measures, the antibacterial envelope has proven to be effective in reducing CIED-related infections.

AREAS COVERED

Published studies investigate the role of antibacterial envelopes in infection prevention and the use of infection risk scores to select high-risk patients undergoing CIED implantation/replacement who can benefit from additional preventive measures.

EXPERT OPINION

A proficient selection of the best candidates for the antibacterial envelope can be the basis for reducing the healthcare system's costs, in line with the principles of cost-effectiveness. Risk scores have been developed to select patients at high risk of CIED infections and their use appears simple and more complete than individual factors alone. Among them, the PADIT score seems to be effective in selecting patients eligible for antibacterial envelope insertion, with a good cost-effectiveness profile.

Rate of device-related infections using an antibacterial envelope in patients undergoing cardiac resynchronization therapy reoperations

AIMS 

Cardiac resynchronization therapy (CRT) reoperations are associated with a particularly high risk of device-related infection (DRI). An antibacterial envelope reduces the occurrence of DRIs in a broad population of moderate-tohigh-risk patients. To investigate the efficacy of an antibacterial envelope in a very high-risk population of patients undergoing CRT reoperation.

METHODS AND RESULTS

In this Danish two-centre, observational cohort study, we included consecutive patients who underwent a CRT pacemaker- or defibrillator reoperation procedure between January 2008 and November 2019. We obtained data from the Danish Pacemaker and ICD Register and through systematic medical chart review. Follow-up was restricted to 2 years. A total of 1943 patients were included in the study of which 736 (38%) received an envelope. Envelope patients had more independent risk factors for infection than non-envelope patients. Sixty-seven (3.4%) patients met the primary endpoint of DRI requiring device system extraction; 50 in the non-envelope group and 17 in the envelope group [4.1% vs. 2.3%, adjusted hazard ratio (HR) 0.52, 95% confidence interval (CI) 0.30-0.90; P = 0.021]. This difference persisted in propensity score analysis (HR 0.51, 95% CI 0.29-0.90; P = 0.019).

CONCLUSION 

Use of an antibacterial envelope was associated with a clinically and statistically significant reduction in DRIs in patients undergoing CRT reoperations. Our results were comparable to those recently reported from a large randomized controlled trial, which is suggestive of a proportional effect of the envelope even in very high-risk patients.

Avoiding implant complications in cardiac implantable electronic devices: what works?

Nearly one in ten patients experience complications in relation to cardiac implantable electronic device (CIED) implantations. CIED complications have serious implications for the patients and for the healthcare system. In light of the rising rates of new implants and consistent rate of complications, primary prevention remains a major concern. To guide future efforts, we sought to review the evidence base underlying common preventive actions made during a primary CIED implantation.

Antibiotic eluting envelopes: evidence, technology, and defining high-risk populations

Cardiovascular implantable electronic devices (CIED) are effective and important components of modern cardiovascular care. Despite the dramatic improvements in the functionality and reliability of these devices, over time patients are at risk for developing several morbidities, the most feared of which are local and systemic infections. Despite significant financial investment and aggressive therapy with hospitalization, intravenous antibiotics, and transvenous lead extraction, the outcomes include a 1-year mortality rate as high as 25%. This risk of infection has increased over time, likely due to the increased complexity of the surgical interventions required to insert and replace these devices. The only way to reduce this morbidity and mortality is to prevent these infections, and other than preoperative antibiotics, there were little data supporting effective therapy until the WRAP-IT trial provided randomized data showing that pocket infections can be reduced by 60% at 12 months and major CIED infections reduced by 40% at 1 year with the use of the absorbable antibiotic eluting envelope in patient CIED procedures at high risk of infection. Not all CIED procedures are at high risk of infection and justify the use of the envelope, but cost-effectiveness data support the use of the antibiotic envelope particularly in patients with defibrillator replacements, revisions, and upgrades, such as to a resynchronization device and in patients with prior CIED infection, history of immunocompromise, two or more prior procedures, or a history of renal dysfunction.

Heparin-mediated antibiotic delivery from an electrochemically-aligned collagen sheet

BACKGROUND

Implantable medical devices and hardware are prolific in medicine, but hardware associated infections remain a major issue.

OBJECTIVE

To develop and evaluate a novel, biologic antimicrobial coating for medical implants.

METHODS

Electrochemically compacted collagen sheets with and without crosslinked heparin were synthesized per a protocol developed by our group. Sheets were incubated in antibiotic solution (gentamicin or moxifloxacin) overnight, and in vitro activity was assessed with five-day diffusion assays against Pseudomonas aeruginosa. Antibiotic release over time from gentamicin-infused sheets was determined using in vitro elution and high performance liquid chromatography (HPLC).

RESULTS

Collagen-heparin-antibiotic sheets demonstrated larger growth inhibition zones against P. aeruginosa compared to collagen-antibiotic alone sheets. This activity persisted for five days and was not impacted by rinsing sheets prior to evaluation. Rinsed collagen-antibiotic sheets did not produce any inhibition zones. Elution of gentamicin from collagen-heparin-gentamicin sheets was gradual and remained above the minimal inhibitory concentration for gentamicin-sensitive organisms for 29 days. Conversely, collagen-gentamicin sheets eluted their antibiotic load within 24 hours. Overall, heparin-associated sheets demonstrated larger inhibition zones against P. aeruginosa and prolonged elution profile via HPLC.

CONCLUSION

We developed a novel, local antibiotic delivery system that could be used to coat medical implants/hardware in the future and reduce post-operative infections.

Cardiovascular implantable electronic devices and native arteriovenous fistula in hemodialysis patients: novel perspectives

The benefits from cardiovascular implantable electronic devices (CIED) implantation in hemodialysis (HD) patients are still far to be thoroughly defined, especially on primary prevention. In addition, CIED placement is not a risk-free procedure, because it could be followed by a not negligible burden of complications that could compromise the health and the vascular access of HD patients. In fact, the arteriovenous fistula (AVF) dysfunction following CIED implantation is usually due to a hemodynamically significant alteration of blood flow. This condition could lead to a potential decrease of dialysis efficacy and a raised risk of thrombosis of both the central vein and the efferent vein of the AVF.The pathological pathway that leads to AVF dysfunction after CIED implantation may involve the irritating actions of the CIED and their leads to the vascular wall in HD patients that are more prone to show previous vascular diseases.The aim of this review is to focus the physiopathology of the CIED-induced AVF dysfunction, the current treatment strategies and the novel perspectives that could be taken into consideration and offered to the HD population to preserve both their AVF and their quality of life.

Surgical Techniques, Complications, and Long-Term Health Effects of Cardiac Implantable Electronic Devices

Cardiovascular implantable electronic device (CIED) has helped with advanced technological improvement in the cardiac field and has been a long-term alternative to medical management. There are different forms of CIEDs such as pacemakers, implantable cardioverter-defibrillators, and cardiac resynchronization therapy. These devices are efficient in establishing near-normal hemodynamics and circulation that ultimately aid physicians to improve the quality of life for their patients. However, there are risk factors that can result in postoperative complications, including infection, lead and pulse generator complications, heart complications, medication-related complications, and psychosocial complications. To ensure optimal outcome of CIED placement, preprocedural measures need to be in place such as matching the right candidate and using appropriate devices. This review aims to highlight the surgical techniques for CIEDs, the associated postoperative complications, and long-term health effects.

Prevention of Cardiac Implantable Electronic Device-Related Infection in Patients With Cancer: The Role of a Comprehensive Prophylactic Bundle Approach That Includes the Antimicrobial Mesh

Background

Oncological patients have several additional risk factors for developing a cardiac implantable electronic device (CIED)–related infection. Therefore, we evaluated the clinical impact of our comprehensive bundle approach that includes the novel minocycline and rifampin antimicrobial mesh (TYRX) for the prevention of CIED infections in patients living with cancer.

Methods

We retrospectively reviewed all consecutive patients who had a CIED placement at our institution during 2012–2017 who received preoperative vancomycin, intraoperative pocket irrigation with bacitracin and polymyxin B, plus TYRX antimicrobial mesh, followed by postoperative oral minocycline.

Results

A total of 154 patients had a CIED, with 97 permanent pacemakers (PPMs), 23 implantable cardioverter defibrillators (ICDs), and 34 cardiac resynchronization therapy (CRT) devices. An underlying solid cancer was present in 62% of patients, while 38% had a hematologic malignancy. Apart from a higher proportion of surgical interventions in the PPM group than in the ICD and CRT groups (P = .007), no other oncologic variables were statistically significantly different between groups. Despite an extensive median follow-up period (interquartile range) of 21.9 (6.7–33.8) months, 16 patients (10%) had a mechanical complication, while only 2 patients (1.3%) developed a CIED infection, requiring the device to be explanted.

Conclusions

Our comprehensive prophylactic bundle approach using TYRX antimicrobial mesh in an oncologic population at high risk for infections was revealed upon extensive follow-up to be both safe and effective in maintaining the rate of CIED infection at 1.3%, well within published averages in the broader population of CIED recipients.

Antibiotic eluting poly(ester urea) films for control of a model cardiac implantable electronic device infection

Cardiac implantable electronic device (CIED) infections acquired during or after surgical procedures are a major complication that are challenging to treat therapeutically, resulting in chronic and sometimes fatal infections. Localized delivery of antibiotics at the surgical site could be used to supplement traditional systemic administration as a preventative measure. Herein, we investigate a cefazolin-eluting l-valine poly(ester urea) (PEU) films as a model system for localized antibiotic delivery for CIEDs. Poly(1-VAL-8) PEU was used to fabricate a series of antibiotic-loaded films with varied loading concentrations (2%, 5%, 10% wt/wt) and thicknesses (40 µm, 80 µm, 140 µm). In vitro release measurements show thickness and loading concentration influence the amount and rate of cefazolin release. Group 10%-140 µm (load-thickness) showed 22.5% release of active pharmaceutical ingredient (API) in the first 24 h and 81.2% of cumulative percent release through day 14 and was found most effective in bacterial clearance in vitro. This group was also effective in clearing a bacterial infection in a model in vivo rat study while eliciting a limited inflammatory response. Our results suggest the feasibility of cefazolin-loaded PEU films as an effective sustained release matrix for localized delivery of antibiotics. SIGNIFICANCE STATEMENT: Implant-associated infections acquired during surgical procedures are a major complication that have proven a challenge to treat clinically, resulting in chronic and sometimes fatal infections. In this manuscript, we investigate an antibiotic-eluting L-valine poly(ester urea) (PEU) films as a model system for localized delivery of cefazolin. Significantly, we demonstrate a wide variation in temporal delivery and dosing within this family of PEUs and show that the delivery can be extended by varying the film thickness. The in vivo results show efficacy in an infected wound model and suggest antibiotic loaded PEU films function as an effective sustained release matrix for localized delivery of antibiotics across a number of clinical indications.

Economic impact of cardiac implantable electronic device infections: cost analysis at one year in a large U.S. health insurer

Aims: Cardiac device infections (CDIs) are serious adverse events associated with morbidity and mortality, significant costs and increased healthcare utilization. The objective of the current study was to characterize the CDI rate by device type, risk factors for infection and healthcare costs from a large U.S. health insurer perspective.Materials and Methods: A retrospective analysis of a large U.S. health insurer database identified commercial and Medicare Advantage with Part D (MAPD) members ≥18 years with ≥1 claim for a cardiac implantable electronic device (CIED) procedure between 01 October 2011 and 31 October 2015. CIEDs included pacemakers (IPG), implantable cardioverter defibrillators (ICDs), and cardiac resynchronization therapy - pacemakers without (CRT-P) and with defibrillation (CRT-D). Probabilities of CDI through one-year post implant were estimated using the Kaplan-Meier method. A regression model with stepwise variable selection was used to select risk factors associated with CDIs.Results: A total of 63,406 patients were included with an overall CDI rate of 1.28% (1.0% de novo and 1.74% replacement devices), varying by device type: IPG = 0.91%; ICD = 1.63%; CRT-p = 1.50%; CRT-D = 2.22%. The average adjusted annual medical costs were 2.4 times greater [95% confidence interval (CI) = 2.1-2.7] for those with an infection compared to those without, and the incremental cost difference was estimated to be $57,322 [95% CI $46,572-$70,484]. Observed risk factors of CDIs included prior device infection [Odds ratio (OR) = 11.356; 95% CI = 7.923-16.276], undergoing a CIED replacement procedure (OR = 1.644; 95% CI = 1.361-1.987), implantation of a high-power device (OR = 1.354; 95% CI = 1.115-1.643), and younger age (age < 65) (OR = 1.607; 95% CI = 1.307-1.976).Conclusions: The CDI rate at one year ranged from 0.91%-2.22% depending on device type. Management of CDIs among commercial and MAPD members is associated with high healthcare expenditures.

The role of an antibiotic envelope in the prevention of major cardiac implantable electronic device infections: A systematic review and meta-analysis

BACKGROUND

Over the past decade, rates of cardiac implantable electronic device (CIED) related infections have increased and been associated with increased morbidity, mortality and financial burden on healthcare systems.

METHODS

To examine the effect of an antibacterial envelope in reducing major CIED related infections, we performed a systematic review and meta-analysis by searching PubMed/MEDLINE, CENTRAL, Google scholar and Clinicaltrials.gov for studies that examined the effect of an antibiotic envelope in reducing major related CIED infections, comprising of device-related endocarditis, systemic infection requiring systemic antibiotics and or device extraction, compared to control up till February 15th, 2020. A random-effects meta-analysis was conducted by calculating risk ratios (RR) and respective 95% confidence intervals (CI).

RESULTS

We include 6 studies that comprise of 11,897 patients, of which 5844 received an antibiotic envelope and 6053 did not. Compared with control, utilization of an antibiotic envelope at the time of procedure was associated with a significant 74% relative risk reduction in major CIED related infections among patients at high risk for infection (RR: 0.26 [95% CI, 0.08-0.85]; P = .03), while no significant reduction was observed among patients enrolled from studies with any risk for infection (RR: 0.53 [95% CI, 0.06-4.52]; P = .56). Additionally, no reduction in mortality among patients that received an envelope compared to control was observed (RR: 1.15 [95% CI, 0.53-2.50]; P = .72).

CONCLUSION

The utilization of an antibiotic envelope at the time of device implantation or upgrade reduces major CIED infections, especially if used in patients perceived to be at higher risk for infection.

Efficacy of antibacterial envelope in prevention of cardiovascular implantable electronic device infections in high-risk patients: A systematic review and meta-analysis

BACKGROUND

Limited evidence is available to determine the efficacy of an antibacterial enveloped (AE) cardiovascular implantable electronic device (CIED).

OBJECTIVE

To assess if the use of antibacterial enveloped devices in high-risk patients are associated with lower chances of major CIED infections and mortality compared to non-enveloped devices.

METHODS

A comprehensive literature search on multiple databases was performed. The relative odds ratio (OR) of major CIED infection and mortality was calculated using a random-effect model.

RESULTS

A total of six studies consisting of 11,897 patients, were included; 5844 with an AE-CIED and 6053 with conventional CIED. In the pooled cohort, patients with AE-CIED had a 66% lower odds of major CIED infection (OR 0.34, 0.13, 0.86, CI 95%, p = 0.02) compared to CIED. Propensity matched analysis showed a 71% lower odds of major infection in the AE-CIED group (OR 0.29, 95% CI 0.10-0.82, p = 0.02). Stratified analysis based on the type of study (retrospective vs. prospective) and duration of follow up (6 months vs. greater than six months) also showed numerically lower infection odds in the AE-CIED. Similarly, the relative odds of mortality were lower in patients with AE-CIED (OR 0.55, 95% CI 0.16-1.91, p = 0.34) compared to CIED patients; however, this difference was statistically non-significant.

CONCLUSION

In high-risk patients, AE-CIED might offer lower odds of CIED infections. It has numerically lower (45%) but statistically non-significant odds of mortality if used in conjunction with the standard infection prevention protocol. More large scale studies and long-term follow-ups are required to validate our findings.

Antibiotic envelope is associated with reduction in cardiac implantable electronic devices infections especially for high-power device-Systematic review and meta-analysis

BACKGROUND

Infections after cardiac implantable electronic device (CIED) placement are associated with significant morbidity and mortality. The incidence of CIED is increasing overtime despite the optimal use of antimicrobial agents. This systematic review and meta-analysis will address the latest evidence on the use of AE to mitigate the risk of CIED infection, and which subset of patients will they benefit the most.

METHODS

We performed a comprehensive search on topics that assesses antibiotic envelope and implantable cardiac electronic device up until August 2019.

RESULTS

There were a total of 32,329 subjects from six studies. Antibiotic envelope was associated with a lower risk of major infection with OR 0.42 [0.19, 0.97], P = .04; I2: 58% and HR 0.52 [0.32, 0.85], P = .009; I2: 80%. Upon sensitivity analysis by removing a study, the OR became 0.40 [0.27, 0.59], P < .001; I2: 46%. Subgroup analysis for 12 months' infection was OR 0.65 [0.43, 0.99], P = .04; I2: 49%. Meta-analysis of propensity-matched cohort showed a reduced risk of infection with AE (OR of 0.14 [0.05, 0.41], P < .001; I2:0%). Mortality was similar in both AE and control groups. Antibiotic envelope reduced the incidence of infection in patients receiving high-power device (OR 0.44 [0.27, 0.73], P = .001; I2:0%) but not low-power device.

CONCLUSION

Antibiotic envelope (TYRX) was found to be safe and effective in reducing the risk of major infections in high-risk patients receiving CIED implantation, especially in those receiving high-power CIED.

Role of antibiotic envelopes in preventing cardiac implantable electronic device infection: A meta-analysis of 14 859 procedures

INTRODUCTION

We conducted an updated meta-analysis assessing the role of antibiotic envelopes in preventing Cardiac implantable electronic devices (CIED)-related infections as compared to standard infection prevention strategies.

METHODS

A systematic search was conducted on Medline/PubMed and EMBASE/Ovid database. We used Mantel-Haenszel method with fixed-effect model to compute risk ratio (RR) with 95% confidence interval (CI). We also performed subgroup and trial sequential analysis on the data.

RESULTS

Antibiotic envelope reduced the risk of both all infections [RR: 0.41, CI: 0.31-0.54, P < .05, I 2 = 75%, χ 2 P < .05] and major infections [RR: 0.48, CI: 0.32-0.70, P < .05, I 2 = 60%, χ 2 P = .04].

CONCLUSION

Prophylactic use of antibiotic envelopes as an adjuvant therapy to standard infection prevention strategies, helps in reducing the risk of CIED infections.

The never-ending story of CIED infection prevention: Shall we WRAP-IT and go?

CIED infection is perceived as substantial, ranging from 1% to 4% in literature depending on different studies and on the population profile, and can appear either as surgical site or endovascular infection or both. Several factors have been found to be associated to CIED infection, that can be summarized as patient-related (clinical profile, associated comorbidities, ongoing treatment as anticoagulants and immunosuppressants), Procedure-related (complexity of CIED surgery, type of surgery, previous pocket exploration), and center-/operator-related (center/operator volume). Thus, it is difficult to disentangle the extent of benefit that any intervention may offer to decrease this threatened complication, owing to its multifaceted complexity. The recently completed PADIT and WRAP-IT trials have significantly improved our knowledge in this field (nearly 20 000 patients enrolled), reporting an infection rate of 1% to 1.2% in control-arm patients and a 20% to 67% infection decrease when incremental antibiotic prophylaxis is added on top of optimized preventative strategies. Observational registries highlighted that participation in a prospective survey of CIED infection dramatically decrease infection rate by optimization of antisepsis protocols and operator awareness, that explains the low event rate observed in PADIT and WRAP-IT. While this consideration prompts each center to engage into a proactive infection prevention program, it makes a point in favor of antibiotic prophylaxis delivered locally in 7 days or more, as enabled by TYRX in the WRAP-IT trial. However, care sustainability (the number needed to treat in the most favorable WRAP-IT scenario is 100) suggests further analysis to understand the settings (patient- or procedure-related) most likely to benefit by such an enhanced prevention strategy.

Antibacterial Envelope to Prevent Cardiac Implantable Device Infection

BACKGROUND

Infections after placement of cardiac implantable electronic devices (CIEDs) are associated with substantial morbidity and mortality. There is limited evidence on prophylactic strategies, other than the use of preoperative antibiotics, to prevent such infections.

METHODS

We conducted a randomized, controlled clinical trial to assess the safety and efficacy of an absorbable, antibiotic-eluting envelope in reducing the incidence of infection associated with CIED implantations. Patients who were undergoing a CIED pocket revision, generator replacement, or system upgrade or an initial implantation of a cardiac resynchronization therapy defibrillator were randomly assigned, in a 1:1 ratio, to receive the envelope or not. Standard-of-care strategies to prevent infection were used in all patients. The primary end point was infection resulting in system extraction or revision, long-term antibiotic therapy with infection recurrence, or death, within 12 months after the CIED implantation procedure. The secondary end point for safety was procedure-related or system-related complications within 12 months.

RESULTS

A total of 6983 patients underwent randomization: 3495 to the envelope group and 3488 to the control group. The primary end point occurred in 25 patients in the envelope group and 42 patients in the control group (12-month Kaplan-Meier estimated event rate, 0.7% and 1.2%, respectively; hazard ratio, 0.60; 95% confidence interval [CI], 0.36 to 0.98; P = 0.04). The safety end point occurred in 201 patients in the envelope group and 236 patients in the control group (12-month Kaplan-Meier estimated event rate, 6.0% and 6.9%, respectively; hazard ratio, 0.87; 95% CI, 0.72 to 1.06; P<0.001 for noninferiority). The mean (±SD) duration of follow-up was 20.7±8.5 months. Major CIED-related infections through the entire follow-up period occurred in 32 patients in the envelope group and 51 patients in the control group (hazard ratio, 0.63; 95% CI, 0.40 to 0.98).

CONCLUSIONS

Adjunctive use of an antibacterial envelope resulted in a significantly lower incidence of major CIED infections than standard-of-care infection-prevention strategies alone, without a higher incidence of complications. (Funded by Medtronic; WRAP-IT ClinicalTrials.gov number, NCT02277990.).

Root cause analysis of epidural spinal cord stimulator implant infections with resolution after implementation of an improved protocol for surgical placement

Background

Placing a spinal stimulator for the purpose of restoring paralysed function is a novel procedure; however, paralysis predisposes people to infection. Preventing surgical site infections is critical to benefit this population.

Objective

The objective of this study was to review the root cause analysis of postoperative wound infections by a hospital epidemiology team following implantation of epidural spinal cord neurostimulators in patients with chronic spinal cord injury.

Methods

A team was assembled to review the case of every individual who had been enrolled to receive a neurostimulator at the facility. A root cause analysis was performed evaluating five categories: the patient; equipment; facility/environment; procedure; and personnel.

Findings

The root cause analysis included 11 patients. Two patients became infected. Three others dehisced their wound without becoming infected. All patients were given preoperative antibiotics on time. A mean of 17 personnel were in the operating room during surgery. Vancomycin powder was used in the patients who either dehisced their wound or became infected.

Conclusions

The root cause analysis provides guidance for other institutions performing the same novel procedure. This analysis did not reveal a direct association, but did generate several areas for improvement including increasing pre-surgical screening, cleaning transient equipment (e.g., computer screens), limiting traffic in the operating room, using new sterile instruments for each stage of the procedure, not reopening the back incision, not applying vancomycin powder, and using an antimicrobial envelope for the stimulator.

Evaluation of Antibiotic-Impregnated Mesh in Preventing the Recurrence of Capsular Contracture

BACKGROUND

Capsular contracture (CC) is the most frequently reported complication following breast augmentation. A growing body of evidence implicates subclinical (biofilm) infection around breast implants as an important cause of CC; however, effective prophylactic and treatment modalities remain controversial.

OBJECTIVES

This article aims to review a single surgeon's experience using an antibiotic-impregnated mesh as a prophylactic measure against biofilm formation and recurrent CC.

METHODS

This study retrospectively reviewed 5 consecutive patients presenting with CC (Baker grades III and IV) who were managed by capsulectomy with implant replacement and simultaneous insertion of an antibiotic-impregnated mesh. Patient demographics and major complications were recorded, including CC recurrence, reoperation, and infection.

RESULTS

Complete correction of the contracture with no recurrence was achieved in all patients at a median followup of 25 months.

CONCLUSIONS

This study demonstrates a novel technique using an antibiotic mesh to reduce bacterial access to breast implants at the time of insertion. Further investigation is warranted with more clinical cases in order to recommend this technique for the management of subclinical infection and CC.

LEVEL OF EVIDENCE: 4

Infection Management

Cardiovascular implantable electronic devices (CIEDs) and the indications for their use have significantly risen over the past decades to include patients who are older with more medical comorbidities. Predictably, the rates of CIED infection have increased substantially. CIED infection is associated with high morbidity, mortality, and financial costs. This article discusses the appropriate management of CIED infections, which is imperative to limit the problems associated with infection.

Reimplantation After Lead Removal

The number of implanted cardiovascular implantable electronic devices (CIEDs) has increased significantly in the last 30 years, which has led to an upsurge in CIED complications, such as infection and lead malfunction requiring CIED extraction. The decision-making process of CIED reimplantation requires meticulous planning that includes careful consideration of several aspects: the reason for extraction, the indication for CIED reimplantation, patients' wishes, timing of reimplantation, the need for a bridging device, and the type and location of device to be reimplanted. In this article, the authors review this decision-making process and the necessary steps to achieve optimal patient outcomes.

Proposal for a Novel Score to Determine the Risk of Cardiac Implantable Electronic Device Infection

INTRODUCTION AND OBJECTIVES

The use of cardiac implantable electronic devices (CIEDs) has expanded in recent years. Infection related to these devices constitutes one of the main complications and is associated with high morbidity, mortality, and financial cost. The aim of this study was to construct a predictive risk score of acquiring CIED infection.

METHODS

We designed a retrospective, nested case-control study. Both cases and controls belonged to a cohort that included all patients who underwent a CIED-related procedure between January 2009 and December 2015. Cases were defined as patients with infection, and 3 infection-free controls were randomly selected from the cohort for each case included.

RESULTS

During the study period, 2323 procedures were performed. A total of 33 CIED-related infections were identified. Ninety-nine patients were selected as controls. Independent risk factors were the Charlson index (OR, 1.33; 95%CI, 1.07-1.67), oral anticoagulation (OR, 3.51; 95%CI, 1.44-8.54), revision or replacement of a previous device (OR, 2.75; 95%CI, 1.12-6.71) and the presence of more than 2 leads (OR, 3.42; 95%CI, 1.25-9.37). A predictive risk score was generated and denominated CIED-AI (Charlson Index, more than 2 leads/Electrodes, Device revision/replacement, oral Anticoagulation, previous Infection). This score had an area under the receiver operating characteristic curve of 0.79 (95%CI, 0.71-0.88).

CONCLUSIONS

The CIED-AI score may help to identify patients at higher risk of infection, who could be candidates for intensive preventive measures.

Cardiovascular Implantable Electronic Device Infections

Infections associated with cardiac implantable electronic devices are increasing and are associated with significant morbidity and mortality. This article reviews the epidemiology, microbiology, and risk factors for acquisition of these infections. The complex diagnostic and management strategies associated with these serious infections are reviewed with an emphasis on recent updates and advances, as well as existing controversies. Additionally, the latest in preventative strategies are reviewed.

Transvenous Lead Extractions: Current Approaches and Future Trends

The use of cardiac implantable electronic devices (CIEDs) has continued to rise along with indications for their removal. When confronted with challenging clinical scenarios such as device infection, malfunction or vessel occlusion, patients often require the prompt removal of CIED hardware, including associated leads. Recent advancements in percutaneous methods have enabled physicians to face a myriad of complex lead extractions with efficiency and safety. Looking ahead, emerging technologies hold great promise in making extractions safer and more accessible for patients worldwide. This review will provide the most up-to-date indications and procedural approaches for lead extractions and insight on the future trends in this novel field.

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.

Cardiac implantable electronic device and vascular access: Strategies to overcome problems

For arrhythmia treatment or sudden cardiac death prevention in hemodialysis patients, there is a frequent need for placement of a cardiac implantable electronic device (pacemaker, implantable cardioverter defibrillator, or cardiac resynchronization device). Leads from a cardiac implantable electronic device can cause central vein stenosis and carry the risk of tricuspid regurgitation or contribute to infective endocarditis. In patients with end-stage kidney disease requiring vascular access and cardiac implantable electronic device, the best strategy is to create an arteriovenous fistula on the contralateral upper limb for a cardiac implantable electronic device and avoidance of central vein catheter. Fortunately, cardiac electrotherapy is moving toward miniaturization and less transvenous wires. Whenever feasible, one should avoid transvenous leads and choose alternative options such as subcutaneous implantable cardioverter defibrillator, epicardial leads, and leadless pacemaker. Based on recent reports on the leadless pacemaker/implantable cardioverter defibrillator effectiveness, in patients with rapid progression of chronic kidney disease (high risk of renal failure) or glomerular filtration rate <20 mL/min/1.73 m², this option should be considered by the implanting cardiologist for future access protection.

Cost-effectiveness of TYRX absorbable antibacterial envelope for prevention of cardiovascular implantable electronic device infection

AIMS

Infection is a major complication of cardiovascular implantable electronic device (CIED) therapy that usually requires device extraction and is associated with increased morbidity and mortality. The TYRX Antibacterial Envelope is a polypropylene mesh that stabilizes the CIED and elutes minocycline and rifampin to reduce the risk of post-operative infection.

METHODS

A decision tree was developed to assess the cost-effectiveness of TYRX vs standard of care (SOC) following implantation of four CIED device types. The model was parameterized for a UK National Health Service perspective. Probabilities were derived from the literature. Resource use included drug acquisition and administration, hospitalization, adverse events, device extraction, and replacement. Incremental cost-effectiveness ratios (ICERs) were calculated from costs and quality-adjusted life-years (QALYs).

RESULTS

Over a 12-month time horizon, TYRX was less costly and more effective than SOC when utilized in patients with an ICD or CRT-D. TYRX was associated with ICERs of £46,548 and £21,768 per QALY gained in patients with an IPG or CRT-P, respectively. TYRX was cost-effective at a £30,000 threshold at baseline probabilities of infection exceeding 1.65% (CRT-D), 1.95% (CRT-P), 1.87% (IPG), and 1.38% (ICD).

LIMITATIONS AND CONCLUSIONS

Device-specific infection rates for high-risk patients were not available in the literature and not used in this analysis, potentially under-estimating the impact of TYRX in certain devices. Nevertheless, TYRX is associated with a reduction in post-operative infection risk relative to SOC, resulting in reduced healthcare resource utilization at an initial cost. The ICERs are below the accepted willingness-to-pay thresholds used by UK decision-makers. TYRX, therefore, represents a cost-effective prevention option for CIED patients at high-risk of post-operative infection.

Enhanced Antimicrobial Effects of Decellularized Extracellular Matrix (CorMatrix) with Added Vancomycin and Gentamicin for Device Implant Protection

BACKGROUND

The incidence of cardiac implantable electronic device (CIED) infections has risen significantly over the past years. Although several devices are currently available to decrease the incidence of infection, most are made from nonviable synthetic material and are more prone to infection than vascularized tissue.

OBJECTIVE

This study was undertaken to assess the resistance to infection of the CorMatrix CanGaroo (CorMatrix Cardiovascular, Roswell, GA, USA), a CIED envelope made of decellularized extracellular matrix (ECM) hydrated in different antibiotic solutions.

METHODS

This study was comprised of two in vitro tests and one animal trial. For all the tests, the ECM was hydrated in a mixture of vancomycin (25 mg/mL) and gentamicin (20 mg/mL) or gentamicin alone (40 mg/mL). The drug elution characteristics were assessed followed by the effectiveness of CanGaroo to prevent the bacterial growth of Staphylococcus aureus and Staphylococcus epidermidis in culture. Then, the direct inoculation of pacemaker implant pockets with both Staphylococcus species was performed in rabbits implanted with either a pacemaker alone or a pacemaker with antibiotic-soaked CorMatrix ECM pouches.

RESULTS

The hydration of CanGaroo envelopes in both antibiotic mixtures resulted in antimicrobial activity against both Staphylococcus species, with an early bolus release of antibiotics followed by a slow release lasting for up to 6 days. In vivo, there was a substantial decrease in the occurrence of infection.

CONCLUSIONS

The hydration of the CanGaroo ECM with an antibiotic solution prevented Staphylococcus species growth in vitro and substantially reduced the incidence of CIED pocket infections in an in vivo rabbit model.