Management of cardiac device-related infections: a review of protocol-driven care

A review on antimicrobial strategies in mitigating biofilm-associated infections on medical implants

Biomedical implants are crucial in providing support and functionality to patients with missing or defective body parts. However, implants carry an inherent risk of bacterial infections that are biofilm-associated and lead to significant complications. These infections often result in implant failure, requiring replacement by surgical restoration. Given these complications, it is crucial to study the biofilm formation mechanism on various biomedical implants that will help prevent implant failures. Therefore, this comprehensive review explores various types of implants (e.g., dental implant, orthopedic implant, tracheal stent, breast implant, central venous catheter, cochlear implant, urinary catheter, intraocular lens, and heart valve) and medical devices (hemodialyzer and pacemaker) in use. In addition, the mechanism of biofilm formation on those implants, and their pathogenesis were discussed. Furthermore, this article critically reviews various approaches in combating implant-associated infections, with a special emphasis on novel non-antibiotic alternatives to mitigate biofilm infections.

Infective Endocarditis among Pediatric Patients with Prosthetic Valves and Cardiac Devices: A Review and Update of Recent Emerging Diagnostic and Management Strategies

Infective endocarditis (IE) is a disease of the endocardium, which leads to the appearance of vegetation on the valves, cardiac structures, or, potentially, vascular endothelium of the heart. The risk of IE can be increased more than 140 times by congenital heart disease (50-59% of all IE), particularly if cyanotic. An increase in mortality may result from IE in patients with a complex cardiac pathology or patients with an implanted prosthetic material, most frequently conduits in a pulmonary position. Cardiac implantable electronic devices (CIED) infective endocarditis is a life-threatening complication representing 10% of all cases of endocarditis. Common signs of presentation are often fever and chills; redness and swelling at the pocket of the pacemaker, including the erosion and exteriorization of the device; and life-threatening sepsis. The use of intracardiac echocardiography for the diagnosis of IE is an innovative method. This may be needed, especially in older children undergoing complex cardiac surgery, when transthoracic echocardiography (TTE) and transesophageal echocardiography (TOE) failed to provide a reliable diagnosis. The 2018 European Heart Rhythm Association (EHRA) experts' consensus statement on transvenous lead extraction recommends complete device removal and antimicrobial therapy for any device-related infection, including CIED-IE. The most detected microorganism was Staphylococcus Aureus. In addition, cardiac surgery and interventional cardiology associated with the placement of prostheses or conduits may increase the risk of IE up to 1.6% for Melody valve implantation. Our manuscript presents a comprehensive review of infective endocarditis associated with cardiac devices and prostheses in the pediatric population, including recent advances in diagnosis and management.

Cardiovascular Implantable Electronic Device Infection and New Insights About Correlation Between Pro-inflammatory Markers and Heart Failure: A Systematic Literature Review and Meta-Analysis

Introduction: Surgical approaches to treat patients with abnormal pro-inflammatory parameters remain controversial, and the debate on the correlation between hematological parameter alteration in cardiac implantable electronic device (CIED) infection and the increase in mortality continues.

Methods: We performed a systematic review using the PubMed, Scopus, and Cochrane Library databases. Twenty-two articles from May 2007 to April 2020 were selected and divided according to the following topics: prevalence of microbes in patients with CIED infection; characteristics of patients with CIED infection; comparison between patients who underwent and did not undergo replantation after device extraction; and correlation between alteration of hematological parameters and poor prognosis analysis.

Results: Epidemiological analysis confirmed high prevalence of male sex, staphylococcal infection, and coagulase-negative staphylococci (CoNS). The most common comorbidity was heart failure. Complete removal of CIED and antimicrobial therapy combination are the gold standard. CIED replacement was associated with higher survival. High preoperative white blood cell count and C-reactive protein levels increased the risk of right ventricular failure (RVF) development. Increased red blood cell distribution width (RDW) value or decreased platelet count was correlated with poor prognosis. No correlation was noted between preoperative leukocytosis and CIED infection.

Discussion: A relevant correlation between leukocytosis and RVF was observed. Heart failure may be related to high RDW values and decreased platelet count. Data on the correlation between hematological parameter alteration and poor prognosis are missing in many studies because of delayed implantation in patients showing signs of infection.

Complications of retained cardiac defibrillator coil left in situ

A 42-year-old man presented to a regional hospital emergency department with a 4-day history of haemoptysis, shortness of breath, pleuritic chest pain, productive cough and subjective fevers. This episode was the third similar presentation in a 2-month period. The patient was known to have dilated cardiomyopathy secondary to amphetamine use and had previously required insertion of automated implantable cardiac defibrillator (AICD). Due to recurrent complications, the AICD had been replaced on two occasions and a superior vena cava (SVC) lead left in situ on its final removal. Clinical examination and investigations revealed lower respiratory tract infection and transthoracic echocardiogram revealed severe left ventricular failure with an ejection fraction of 16%. The patient was admitted under the general medical team for treatment and investigation of suspected bacteraemia and septicaemia secondary to colonisation of the retained AICD lead. He spent 6 days as an in-patient and was discharged on home where he was to be followed up by the advanced heart failure team in a tertiary centre for consideration of new AICD insertion and to explore possibility of retained coil removal. This case report discusses the concerns surrounding retained SVC leads and potential clinical sequalae. As this patient presented three times within a period of 2 months, it was suspected retained SVC lead was a predisposing factor for recurrent lower respiratory infection.

The Diagnosis and Treatment of Pacemaker-Associated Infection

BACKGROUND

Approximately 105 000 cardiac electronic devices are newly implanted in Germany each year. Germany has the highest implantation rate with respect to population of any European country. Infections in cardiac implants are serious complications, with an associated in-hospital mortality of 5-15%. It is thus very important to optimize the diagnostic and therapeutic strategies by which such infections can be detected early and treated effectively.

METHODS

This review is based on pertinent publications retrieved by a search in PubMed, with special attention to the current recommendations of international medical specialty societies.

RESULTS

According to the international literature, the incidence of device-associated infection is 1.7% (in six months) for implanted defibrillators and 9.5% (in two years) for resynchronization devices. No absolute figures on infection rates are available for Germany. Infection can involve either the site where the impulse generator is implanted or the intravascular portion of the electrodes. The most important elements of the diagnostic evaluation are: assessment of the local findings; pathogen identification by culture of peripheral blood, swabs of the infected site, or material recovered at surgery; and transesophageal echocardiography to detect endocarditic deposits on the electrodes or cardiac valves. The treatment consists of appropriate antibiotic administration and the complete removal of all foreign material. These special extractions are generally performed via the transvenous route. With the aid of various sheath systems, the procedure can be carried out safely and effectively, with a success rate above 95% and a complication rate below 3%. The indications for the implantation of a new device after eradication of the infection should be critically reassessed.

CONCLUSION

Untreated infection carries a high mortality. Evaluation and treatment according to a standardized clinical algorithm facilitate correct and timely diagnosis and the choice of an appropriate therapeutic strategy.

Racial and ethnic healthcare disparities in patients undergoing laser lead extraction

BACKGROUND

The rate of cardiovascular implantable electronic device infections (CIEDIs) has mirrored or exceeded the increased use of implantable cardiac devices in the United States. The presence of racial and ethnic disparities associated with CIEDIs has not been published. Our aim is to describe the presence of racial and ethnic disparities with respect to the management of CIEDIs.

METHODS

We reviewed a prospective single-center registry for patients undergoing removal of an implantable cardiac device between 1/2004 and 1/2016. 1173 consecutive patients underwent device extraction. 699 patients were identified as having an infection, 305 were identified as Caucasian and 394 were minorities (91 African Americans, 303 Hispanics). Patients had pre-operative transesophageal echocardiograms (TEEs) and collection of blood and exudate cultures. All underwent complete hardware extraction; leads were removed through the use of locking stylets and traction or laser extraction. En-bloc capsulectomy was performed with intraoperative specimen collection from pocket tissue, exudate, lead tips, and vegetations.

RESULTS

Minority patients were: younger (67.9 ± 14.5 years vs 72.4 ± 13.2 years), had a higher proportion of male gender, diabetes, and chronic renal failure (p < 0.001). Minorities experienced a higher rate of complications during extraction and a longer hospitalization (15.3 ± 9.9 days versus 17.4 ± 13.4 days, p < 0.001). There was no significant difference between the proportion of types of infection in both groups.

CONCLUSION

Minority patients with CIEDIs experienced more procedural complications during extraction and had a significantly longer length of index hospitalization than Caucasian patients.

Attempted salvage of infected cardiovascular implantable electronic devices: Are there clinical factors that predict success?

BACKGROUND

Published guidelines mandate complete device removal in cases of cardiovascular implantable electronic device (CIED) infection. Clinical predictors of successful salvage of infected CIEDs have not been defined.

METHODS

Data from the Multicenter Electrophysiologic Device Infection Collaboration, a prospective, observational, multinational cohort study of CIED infection, were used to investigate whether clinical predictors of successful salvage of infected devices could be identified.

RESULTS

Of 433 adult patients with CIED infections, 306 (71%) underwent immediate device explantation. Medical management with device retention and antimicrobial therapy was initially attempted in 127 patients (29%). "Early failure" of attempted salvage occurred in 74 patients (58%) who subsequently underwent device explantation during the index hospitalization. The remaining 53 patients (42%) in the attempted salvage group retained their CIED. Twenty-six (49%) had resolution of CIED infection (successful salvage group) whereas 27 patients (51%) experienced "late" salvage failure. Upon comparing the salvage failure group, early and late (N = 101), to the group experiencing successful salvage of an infected CIED (N = 26), no clinical or laboratory predictors of successful salvage were identified. However, by univariate analysis, coagulase-negative staphylococci as infecting pathogens (P = 0.0439) and the presence of a lead vegetation (P = 0.024) were associated with overall failed salvage.

CONCLUSIONS

In patients with definite CIED infections, clinical and laboratory variables cannot predict successful device salvage. Until new data are forthcoming, device explantation should remain a mandatory and early management intervention in patients with CIED infection in keeping with existing expert guidelines unless medical contraindications exist or patients refuse device removal.

Reimplantation and Repeat Infection After Cardiac-Implantable Electronic Device Infections: Experience From the MEDIC (Multicenter Electrophysiologic Device Infection Cohort) Database

BACKGROUND

Infection is a serious complication of cardiovascular-implantable electronic device implantation and necessitates removal of all hardware for optimal treatment. Strategies for reimplanting hardware after infection vary widely and have not previously been analyzed using a large, multicenter study.

METHODS AND RESULTS

The MEDIC (Multicenter Electrophysiologic Device Infection Cohort) prospectively enrolled subjects with cardiovascular-implantable electronic device infections at multiple institutions in the United States and abroad between 2009 and 2012. Reimplantation strategies were evaluated overall, and every patient who relapsed within 6 months was individually examined for clinical information that could help explain the negative outcome. Overall, 434 patients with cardiovascular-implantable electronic device infections were prospectively enrolled at participating centers. During the initial course of therapy, complete device removal was done in 381 patients (87.8%), and 220 of them (57.7%) were ultimately reimplanted with new devices. Overall, the median time between removal and reimplantation was 10 days, with an interquartile range of 6 to 19 days. Eleven of the 434 patients had another infection within 6 months, but only 4 of them were managed with cardiovascular-implantable electronic device removal and reimplantation during the initial infection. Thus, the repeat infection rate was low (1.8%) in those who were reimplanted. Patients who retained original hardware had a 11.3% repeat infection rate.

CONCLUSIONS

Our study findings confirm that a broad range of reimplant strategies are used in clinical practice. They suggest that it is safe to reimplant cardiac devices after extraction of previously infected hardware and that the risk of a second infection is low, regardless of reimplant timing.

Prevention of Cardiac Implantable Electronic Device Infections: Update and Evaluation of the Potential Role for Capsulectomy or the Antibiotic Pouch

Cardiac implantable electronic device (CIED) infections can have devastating implications for patient morbidity and mortality. Over the past decade, the infection rate has risen out of proportion to implant rates, and has prompted the development of innovative solutions designed to reduce infections. The first section of this review provides a summary of the contemporary knowledge regarding the incidence, prevalence, microbiology, and risk factors for cardiac implantable electronic device infections. The second section addresses prevention with an emphasis on the potential role of novel procedural approaches, such as capsulectomy and the antibacterial envelope, in reducing CIED infection.

Lead-related infective endocarditis: Factors influencing early and long-term survival in patients undergoing transvenous lead extraction

BACKGROUND

Lead-related infective endocarditis (LRIE) is a serious infectious disease with uncertain prognosis.

OBJECTIVE

The purpose of this study was to evaluate the factors that influence survival in patients with LRIE undergoing transvenous lead extraction (TLE).

METHODS

Clinical data obtained from 500 consecutive patients with LRIE undergoing TLE in the reference center in the years 2006 to 2015 were retrospectively analyzed. We evaluated the effect of demographic, clinical, and procedure-related factors on 30-day and long-term survival (mean 3-year follow-up).

RESULTS

Analysis of 30-day survival after TLE revealed 19 deaths (3.8%), with long-term mortality (mean 3-year follow-up) of 29.3% (146 deaths). Multivariate analysis showed unfavorable effects of age (hazard ratio [HR] 1.056, 95% confidence interval [CI] 1.030-1.082); decreased left ventricular ejection fraction (HR 0.687, 95% CI 0.545-0.866); renal failure (HR 3.099, 95% CI 1.865-5.150); and presence of vegetation fragments remaining after TLE (HR 1.384, 95% CI 1.089-1.760). Log-rank test and Kaplan-Meier survival curves demonstrated statistically worse prognosis in patients with large vegetations (>2 cm) and with vegetation remnants. Better prognosis was associated with LRIE coexisting with generator pocket infection.

CONCLUSION

Long-term mortality in LRIE patients is still high. Factors that influence negatively on prognosis include large cardiac vegetations and their remnants after TLE. Such vegetations develop most frequently in patients with decreased left ventricular ejection fraction and renal failure. Probably, early detection of LRIE would tend to limit the formation of large vegetations that invade the adjacent cardiac structures.

Cardiac device infection: Review based in the experience of a single center

INTRODUCTION

The incidence of cardiac implantable electronic device infections has increased significantly over the years and they are associated with significant morbidity and mortality. The epidemiology in the Central region of Portugal is not known.

OBJECTIVE AND METHODS

To characterize cardiac implantable electronic device infections through a retrospective study of 3158 patients admitted to our center between January 2008 and September 2014 and to review the subject in the light of the current state of the art.

RESULTS

The infection rate was 1.48% (pacemakers 1.21%, cardiac defibrillator/resynchronization devices 5.40%). The study population consisted of 47 patients with a mean age of 65±19 years, predominantly male (72.3%). Infections were mainly of pacemakers, the main device implanted in our population (n=2954), and most occurred late after first implantation. Clinically, most patients presented with fever and local inflammation. Blood cultures identified mainly Gram-positive microorganisms. Empiric antibiotic therapy with vancomycin was instituted in all patients, associated with gentamicin in 57%. The device was extracted in the majority of cases (72%). During follow-up (32±22 months) eight patients died (17%), seven of cardiovascular cause (15%), and seven were readmitted with device infection (15%).

CONCLUSIONS

Our rate of infection was low, similar to other published series, with a higher rate in cardiac defibrillator/resynchronization devices. After standard treatment with antibiotic therapy and device extraction, the prognosis was good.

Treatment of Infected Cardiac Implantable Electronic Devices

With their rising benefits, cardiac implantable electronic devices (CIEDs) such as pacemakers and left ventricular assist devices (LVADs) have witnessed a sharp rise in use over the past 50 years. As indications for use broaden, so too does their widespread employment with its attendant rise of CIED infections. Such large numbers of infections have inspired various algorithms mandating treatment. Early diagnosis of inciting organisms is crucial to tailoring appropriate antibiotic and or antifungal treatment. In addition, surgical debridement and explant of the device have been a longstanding modality of care. More novel therapies focus on salvage of the device by way of serial washouts and instilling drug-eluting antibiotic impregnated beads into the wound. The wound is then serially debrided until clean and closed. This technique is better suited to patients whose device cannot be removed, patients who are poor candidates for cardiac surgery, or patients who have failed conventional prior treatments.

Cardiac implantable electronic device infection in patients with end-stage renal disease

INTRODUCTION

Cardiac implantable electronic devices (CIED) are increasingly being used in end-stage renal disease (ESRD) patients. These patients have a high risk of device infection.

OBJECTIVES

To study the optimal management of device infections in patients with ESRD.

METHOD

We used the United States Renal Data System (USRDS) to assess the presence of a CIED and associated comorbidities, risk factors for infection, and mortality following device extraction or medical management in ESRD patients with CIED infection. Univariable, multivariable, and survival analyses were performed using USRDS data from 2005 to 2009.

RESULTS

Of 546,769 patients, 6.4% had CIED and 8.0% of those developed CIED infection. The major risk factors for device infection were black race, temporary dialysis catheter, and body mass index >25. Patients with artificial valves were excluded from the analysis. Only 28.4% of infected CIED were removed. CIED removal was more common in those with congestive heart failure. The median time to death following diagnosis of a CIED infection was 15.7 months versus 9.2 months for those treated via device extraction versus medical-only therapy (hazard ratio: 0.75; 95% confidence interval: 0.68-0.82).

CONCLUSION

Patients with ESRD and infected CIEDs have a poor prognosis. Rates of device extraction are low, but this strategy appears to be associated with modest improvement in survival.

[Fatal surgical extraction of cardiac resynchronisation therapy defibrillator leads in a context of endocarditis due to methicillin-resistant Staphylococcus epidermidis. A case report and review of literature]

A 82-year-old man equipped with a cardiac resynchronisation therapy defibrillator for dilated cardiomyopathy with normal coronary arteries, in complete atrioventricular block, develops six months after a change of the generator-pocket a severe endocarditis due to a methicillin-resistant Staphylococcus epidermidis with a large lead vegetation. After 4 days of adapted antimicrobial therapy, a surgical device removal is realised with unfortunately a fatal end during extraction. This observation points out the severity of cardiovascular device infections in old and weak population, as well as the difficulty of treatment choices because of both infectious and rhythmic constraints. The lead extraction is a strong recommendation but the modality and timing of extraction are not consensual, especially in cardioverter defibrillator-dependent patients. Surgical removal remains an alternative to percutaneous lead extraction but with a higher operative risk.

Clinical manifestations of lead-dependent infective endocarditis: analysis of 414 cases

It is important to identify clinical manifestations of lead-dependent infective endocarditis (LDIE), as it begins insidiously with the slow development of nonspecific symptoms. Clinical data from 414 patients with the diagnosis of LDIE according to Modified Duke Lead Criteria (MDLC) were analyzed. Patients with LDIE had been identified in a population of 1,426 subjects submitted to transvenous lead extraction (TLE) in the Reference Clinical Cardiology Center in Lublin between 2006 and 2013. The symptoms of LDIE and pocket infection were detected in 62.1 % of patients. The mean duration of LDIE symptoms prior to referral for TLE was 6.7 months. Fever and shivers were found in 55.3 % of patients, and pulmonary infections in 24.9 %. Vegetations were detected in 67.6 % of patients, and positive cultures of blood, lead, and pocket in 34.5, 46.4, and 30.0 %, respectively. The most common pathogens in all type cultures were coagulase-negative staphylococci (CNS), with Staphylococcus epidermidis domination; the second most common organism was Staphylococcus aureus. 76.3 % of patients were treated with empirical antibiotic therapy before hospitalization due to TLE. In the laboratory tests, the mean white blood cell count was 9,671 ± 5,212/μl, mean erythrocyte sedimentation rate 43 mm, C-reactive protein (CRP) 46.3 mg/dl ± 61, and procalcitonin 1.57 ± 4.4 ng/ml. The multivariate analysis showed that the probability of LDIE increased with increasing CRP. The diagnosis of LDIE based on MDLC may be challenging because of a relatively low sensitivity of major criteria, which is associated with early antibiotic therapy and low usefulness of minor criteria. The important clinical symptoms of LDIE include fever with shivering and recurrent pulmonary infections. The most specific pathogens were Staphylococcus epidermidis and Staphylococcus aureus. Laboratory tests most frequently revealed normal white blood cell count, relatively rarely elevated procalcitonin level, and significantly increased erythrocyte sedimentation rate (ESR) and CRP. This constellation of signs should prompt a more thorough search for LDIE.

Two cases of cardiac device-related endocarditis due to Streptococcus dysgalactiae subsp. equisimilis (group C or G streptococci)

Background

Cardiac device-related endocarditis is a very rare clinical manifestation of S. dysgalactiae subsp. equisimilis disease. This pathogen is a common cause of cellulitis. We here report two cases of cardiac device-related endocarditis due to Streptococcus dysgalactiae subsp. equisimilis. Blood cultures yielded this pathogen and both patients had recurrent bacteremia. Transthoracic and transesophageal echocardiography revealed lead vegetations. This is a new description of this pathogen to cause cardiac device-related endocarditis.

Case presentation

The first case is a 79-year-old finnish woman who received a dual-chamber pacemaker for intermittent complete heart block in April 2011. She had three episodes of S. dysgalactiae subsp. equisimilis bacteremia. During first episode she had arthritis of glenohumeral joint. Focus was unknown in the second and third bacteremic episodes. During third bacteremic episode transesophageal echocardiography (TEE) revealed lead vegetation. Patient underwent successful complete system removal. She was treated with benzylpenicillin four million IU six times a day for four weeks intravenously. The second case is a 92-year-old finnish man. A dual-chamber pacemaker was implanted on June 2012 due to total heart block. He had recurrent S. dysgalactiae subsp. equisimilis bacteremia with cellulitis. During the second bacteremic episode transthoracic echocardiography (TTE) was performed because of persistent fever. Echocardiography revealed lead vegetation. Abdominal CT revealed also an abscess in the psoas region. This elderly patient was very fragile, and the pacemaker system was not extracted. Therapy was continued with benzylpenicillin four million IU six times a day for six weeks intravenously and thereafter suppressive treatment with amoksisillin 500 mg three times a day was initiated.

Conclusion

Streptococcus dysgalactiae subsp. equisimilis (group C and G streptococci) seldom cause cardiac device endocarditis. Both patients had recurrent bacteremia of S. dysgalactiae subsp. equisimilis and echocardiography revealed cardiac device-related endocarditis. These cases emphasize the importance of considering endocarditis in elderly persons having cardiac devices together with the presence of unexplained bacteremia, fever without focus or persistent fever.

Implantable cardioverter defibrillator lead-related methicillin resistant Staphylococcus aureus endocarditis: Importance of heightened awareness

Methicillin resistant Staphylococcus aureus (MRSA) septicemia is associated with high morbidity and mortality especially in patients with immunosuppression, diabetes, renal disease and endocarditis. There has been an increase in implantation of cardiac implantable electronic devices (CIED) with more cases of device-lead associated endocarditis been seen. A high index of suspicion is required to ensure patient outcomes are optimized. The excimer laser has been very efficient in helping to ensure successful lead extractions in patients with CIED infections. We present an unusual case report and literature review of MRSA septicemia from device-lead endocarditis and the importance of early recognition and prompt treatment.