Permanent pacemaker and implantable cardioverter defibrillator infections: seven years of diagnostic and therapeutic experience of a single center

Unravelling staphylococcal small-colony variants in cardiac implantable electronic device infections: clinical characteristics, management, and genomic insights

Objectives

Staphylococcal small-colony variants (SCVs) are common in cardiac implantable electronic device (CIED) infections. This is the first retrospective and multi-case study on CIED infections due to staphylococcal SCVs, aiming to provide a theoretical basis for the clinical management of CIED and device-related infections caused by staphylococcal SCVs.

Methods

Ninety patients with culture positive CIED infections were enrolled between 2021 and 2022. We compared the demographic and clinical characteristics of patients with and without SCVs and performed genomic studies on SCVs isolates.

Results

Compared to patients without SCVs, those with SCVs had a longer primary pacemaker implantation time and were more likely to have a history of device replacement and infection. They showed upregulated inflammatory indicators, especially higher NEUT% (52.6 vs. 26.8%, P = 0.032) and they had longer hospital stays (median 13 vs. 12 days, P = 0.012). Comparative genomics analysis was performed on Staphylococcus epidermidis wild-type and SCVs. Some genes were identified, including aap, genes encoding adhesin, CHAP domain-containing protein, LPXTG cell wall anchor domain-containing protein, and YSIRK-type signal peptide-containing protein.

Conclusion

Staphylococcal SCVs affect the clinical characteristics of CIED infections. The process of staphylococcal SCVs adherence, biofilm formation, and interaction with neutrophils play a vital role.

The Systemic Immune-Inflammation Index and Predicting Cardiac Implantable Electronic Device Infections

This study aimed to evaluate the utility of the systemic immune-inflammation index (SII) in predicting the development of Cardiac Implantable Electronic Device (CIED) infections. A retrospective analysis was performed using the medical records of 2185 patients who underwent CIED (including de novo, revision, or upgrade) implantation at our institution from January 2012 to December 2019. We recorded CIED infections and risk factors according to the patient, device, and procedural characteristics during the median 28.7 months (6.2-56.8) follow-up. CIED infections were identified in 52 patients. Diabetes, chronic renal disease, SII before implantation, new cardiac resynchronization therapy (CRT) implantation, CRT-battery replacement, revision or upgrade, and the number of previous procedures were independent predictors of CIED infections. The area under the curve (AUC) of SII to predict CIED infection was .733 (95% CI: .654-.811). A raised SII may be a useful predictor of CIED infection.

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.

Risk factors for cardiac implantable electronic device infections: a nationwide Danish study

AIMS

Cardiac implantable electronic device (CIED) infection is a severe complication to modern management of cardiac arrhythmias. The CIED type and the type of surgery are recognized as risk factors for CIED infections, but knowledge of patient-related risk factors is scarce. This study aimed to identify lifelong patient-related risk factors for CIED infections.

METHODS AND RESULTS

Consecutive Danish patients undergoing a CIED implantation or reoperation between January 1996 and April 2018 were included. The cohort consisted of 84 429 patients undergoing 108 494 CIED surgeries with a combined follow-up of 458 257 CIED-years. A total of 1556 CIED explantations were classified as either pocket (n = 1022) or systemic CIED infection (n = 534). Data were cross-linked with records from the Danish National Patient Registry and the Danish National Prescription Registry. Using multiple-record and multiple-event per subject proportional hazard analysis, specific patient-related risk factors were identified but with several variations amongst the subtypes of CIED infection. CIED reoperations were associated with the highest risk of pocket CIED infection but also CIED type, young age, and prior valvular surgery [hazard ratio (HR): 1.62, 95% confidence interval (CI): 1.29-2.04]. Severe renal insufficiency/dialysis (HR: 2.40, 95% CI: 1.65-3.49), dermatitis (HR: 2.80, 95% CI: 1.92-4.05), and prior valvular surgery (HR: 2.09, 95% CI: 1.59-2.75) were associated with the highest risk of systemic CIED infections. Congestive heart failure, ischaemic heart disease, malignancy, chronic obstructive pulmonary disease, and temporary pacing were not significant at multivariate analysis.

CONCLUSION

Specific comorbidities and surgical procedures were associated with a higher risk of CIED infections but with variations amongst pocket and systemic CIED infection. Pocket CIED infections were associated with CIED reoperations, young age and more complex type of CIED, whereas systemic CIED infections were associated with risk factors predisposing to bacteraemia.

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.

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.

Epidemiology of cardiac implantable electronic device infections: incidence and risk factors

Cardiac implantable electronic device (CIED) infection is a potentially devastating complication of CIED procedures, causing significant morbidity and mortality for patients. Of all CIED complications, infection has the greatest impact on mortality, requirement for re-intervention and additional hospital treatment days. Based on large prospective studies, the infection rate at 12-months after a CIED procedure is approximately 1%. The risk of CIED infection may be related to several factors which should be considered with regards to risk minimization. These include technical factors, patient factors, and periprocedural factors. Technical factors include the number of leads and size of generator, the absolute number of interventions which have been performed for the patient, and the operative approach. Patient factors include various non-modifiable underlying comorbidities and potentially modifiable transient conditions. Procedural factors include both peri-operative and post-operative factors. The contemporary PADIT score, derived from a large cohort of CIED patients, is useful for the prediction of infection risk. In this review, we summarize the key information regarding epidemiology, incidence and risk factors for CIED infection.

Postimplantation pocket hematoma increases risk of cardiac implantable electronic device infection: A meta-analysis

INTRODUCTION

 Several studies have shown an inconsistent relationship between postimplantation pocket hematoma and cardiac implantable electronic device (CIED) infection. In this study, we performed a systematic review and meta-analysis to explore the effect of postimplantation hematoma and the risk of CIED infection.

METHODS

 We searched the databases of MEDLINE and EMBASE from inception to March 2020. Included studies were cohort studies, case-control studies, cross-sectional studies, and randomized controlled trials that reported incidence of postimplantation pocket hematoma and CIED infection during the follow-up period. CIED infection was defined as either a device-related local or systemic infection. Data from each study were combined using the random effects, generic inverse variance method of Der Simonian and Laird to calculate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Fourteen studies were included in final analysis, involving a total of 28 319 participants. In random-effect model, we found that postimplantation pocket hematoma significantly increases the risk of overall CIED infection (OR = 6.30, 95% CI: 3.87-10.24, I 2 = 49.3%). There was no publication bias observed in the funnel plot as well as no small-study effect observed in Egger's test.

CONCLUSIONS

Our meta-analysis demonstrated that postimplantation pocket hematoma significantly increases the risk of CIED infection. Precaution should be taken during device implantation to reduce postimplantation hematoma and subsequent CIED infection.

Device-related infection in de novo transvenous implantable cardioverter-defibrillator Medicare patients

BACKGROUND

Cardiac device infection is a serious complication of implantable cardioverter-defibrillator (ICD) placement and requires complete device removal with accompanying antimicrobial therapy for durable cure. Recent guidelines have highlighted the need to better identify patients at high risk of infection to assist in device selection.

OBJECTIVE

To estimate the prevalence of infection in de novo transvenous (TV) ICD implants and assess factors associated with infection risk in a Medicare population.

METHODS

A retrospective cohort study was conducted using 100% Medicare administrative and claims data to identify patients who underwent de novo TV-ICD implantation (July 2016-December 2017). Infection within 720 days of implantation was identified using ICD-10 codes. Baseline factors associated with infection were identified by univariable logistic regression analysis of all variables of interest, including conditions in Charlson and Elixhauser comorbidity indices, followed by stepwise selection criteria with a P ≤ .25 for inclusion in a multivariable model and a backwards, stepwise elimination process with P ≤ .1 to remain in the model. A time-to-event analysis was also conducted.

RESULTS

Among 26,742 patients with de novo TV-ICD, 519 (1.9%) developed an infection within 720 days post implant. While more than half (54%) of infections occurred during the first 90 days, 16% of infections occurred after 365 days. Multivariable analysis revealed several significant predictors of infection: age <70 years, renal disease with dialysis, and complicated diabetes mellitus.

CONCLUSION

The rate of de novo TV-ICD infection was 1.9%, and identified risk factors associated with infection may be useful in device selection.

Strategies to Prevent Cardiac Implantable Electronic Device Infection

The association between the risk of mortality and cardiovascular implantable electronic device (CIED) infections has been well-established in the literature. As CIED implantations have increased in frequency in the past few decades, the incidence of CIED-related infections has also risen. Given the morbidity, mortality, and health-care costs associated with CIED infections, the prevention of device-related infection is a critical goal. Risk factors for developing CIED infections can be categorized as patient-, procedure-, or device-related. Numerous studies have highlighted different strategies for preventing CIED-related infections, which include patient optimization, device selection, and periprocedural preparation and treatment. Nonetheless, as the comorbidity burden of patients undergoing CIED implantation continues to increase, significant challenges in the successful elimination of CIED-related infections remain. This review provides a comprehensive overview of available evidence-based approaches and strategies to reduce the risk of CIED infections.

The European Society of Cardiology Cardiac Resynchronization Therapy Survey II: A comparison of cardiac resynchronization therapy implantation practice in Europe and France

BACKGROUND

The first European Cardiac Resynchronization Therapy (CRT) Survey, conducted in 2008-2009, showed considerable variations in guideline adherence and implantation practice. A second prospective survey (CRT Survey II) was then performed to describe contemporary clinical practice regarding CRT among 42 European countries.

AIM

To compare the characteristics of French CRT recipients with the overall European population of CRT Survey II.

METHODS

Demographic and procedural data from French centres recruiting all consecutive patients undergoing either de novo CRT implantation or an upgrade to a CRT system were collected and compared with data from the European population.

RESULTS

A total of 11,088 patients were enrolled in CRT Survey II, 754 of whom were recruited in France. French patients were older (44.7% aged≥75 years vs 31.1% in the European group), had less severe heart failure symptoms, a higher baseline left ventricular ejection fraction and fewer co-morbidities. Additionally, French patients had a shorter intrinsic QRS duration (19.1% had a QRS<130ms vs 12.3% in the European cohort). Successful implantation rates were similar, but procedural and fluoroscopy times were shorter in France. French patients were more likely to receive a CRT pacemaker than European patients overall. Of note, antibiotic prophylaxis was reported to be administered less frequently in France, and a higher rate of early device-related infection was observed. Importantly, French patients were less likely to receive optimal drugs for treating heart failure at hospital discharge.

CONCLUSION

This study highlights contemporary clinical practice in France, and describes substantial differences in patient selection, implantation procedure and outcomes compared with the other European countries participating in CRT Survey II.

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.

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.

Device infections in implantable cardioverter defibrillators versus permanent pacemakers: A systematic review and meta-analysis

INTRODUCTION

Recent studies suggest that implantable cardioverter defibrillators (ICDs) are associated with increased risk of cardiac implantable electronic device (CIED) infections when compared with permanent pacemakers (PPMs). However, there were controversies among studies. In this study we performed a systematic review and meta-analysis to explore the risk of device infection in ICD versus PPM.

METHODS

We searched the databases of MEDLINE and EMBASE from inception to January 2019. Data from each study were combined using the random-effects, generic inverse variance method of Der Simonian and Laird to calculate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

Twenty-seven studies involving 202 323 CIEDs (36 782 ICDs and 165 541 PPMs) were included. Infections occurred from 9 days to 6 years postoperatively. When compared with PPM, ICD had a significantly higher risk of device infection in overall analysis (OR = 1.62, 95% CI: 1.29-2.04). The risk was seen in subgroups such as single chamber or dual chamber device (OR = 1.57, 95% CI: 1.18-2.09), de novo implantation (OR = 1.62, 95% CI: 1.29-2.69), revision implantation (OR = 1.63, 95% CI: 1.24-2.13), and cardiac resynchronization therapy (CRT) (OR = 1.75, 95% CI: 1.18-2.60). CRT-defibrillator increased risk of infection over CRT-pacemaker in revision implantation (OR = 1.81, 95% CI: 1.20-2.74) but not in de novo implantation (OR = 1.07, 95% CI: 0.23-4.88). The increased risk of infection among defibrillator was higher in CRT compared to non-CRT but not significant (P = 0.654).

CONCLUSIONS

Our meta-analysis demonstrates a statistically significant increased risk of device infection in CIED patients who received ICD when compared to PPM.

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.

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.

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.

Percutaneous Lead Extraction in Infection of Cardiac Implantable Electronic Devices: a Systematic Review

INTRODUCTION

In the last two decades, the increased number of implants of cardiac implantable electronic devices has been accompanied by an increase in complications, especially infection. Current recommendations for the appropriate treatment of cardiac implantable electronic devices-related infections consist of prolonged antibiotic therapy associated with complete device extraction. The purpose of this study was to analyze the importance of percutaneous extraction in the treatment of these devices infections.

METHODS

A systematic review search was performed in the PubMed, BVS, Cochrane CENTRAL, CAPES, SciELO and ScienceDirect databases. A total of 1,717 studies were identified and subsequently selected according to the eligibility criteria defined by relevance tests by two authors working independently.

RESULTS

Sixteen studies, describing a total of 3,354 patients, were selected. Percutaneous extraction was performed in 3,081 patients. The average success rate for the complete percutaneous removal of infected devices was 92.4%. Regarding the procedure, the incidence of major complications was 2.9%, and the incidence of minor complications was 8.4%. The average in-hospital mortality of the patients was 5.4%, and the mortality related to the procedure ranged from 0.4 to 3.6%. The mean mortality was 20% after 6 months and 14% after a one-year follow-up.

CONCLUSION

Percutaneous extraction is the main technique for the removal of infected cardiac implantable electronic devices, and it presents low rates of complications and mortality related to the procedure.

New Insights into Predictors of Cardiac Implantable Electronic Device Infection

Infection is an important complication of cardiac implantable electronic device procedures. To further study the factors associated with infection, we retrospectively reviewed the records of 3,205 consecutive patients who had undergone de novo or revision cardiac electronic device implantation at our institution from March 2011 through March 2015. We recorded all infections and specified whether they were related to the characteristics of the patient, device, or procedure. To identify predictors of infection, we performed multivariate analysis. Device infections were identified in 85 patients (2.7%), at a mean follow-up time of 27 ± 11 months. The main predictors of device infection were use of an implantable cardioverter-defibrillator or a cardiac resynchronization therapy defibrillator device (odds ratio [OR]=16; 95% CI, 4.14-61.85; P=0.0001), stage 3 chronic kidney disease (OR=9.41; 95% CI, 1.77-50.04; P=0.009), a revision procedure (OR=8.8; 95% CI, 3.37-23.2; P=0.0001), or postoperative hematoma (OR=6.9; 95% CI, 1.58-30.2; P=0.01). We also identified 2 novel predictors of infection: a low body mass index of <20 kg/m² (OR=1.03; 95% CI, 1.01-1.06; P=0.005), and use of povidone-iodine rather than chlorhexidine-alcohol for topical antisepsis (OR=4.4; 95% CI, 2.01-9.4; P=0.03). We conclude that comorbidities, device characteristics, procedure types, and postoperative noninfective complications all increase the risk of device infection after a cardiac implantable electronic device procedure.

Repeated procedures at the generator pocket are a determinant of implantable cardioverter-defibrillator infection

BACKGROUND

Rates of cardiac-device infections have increased in recent years, but the current incidence and risk factors for infection in patients with implantable cardioverter-defibrillators (ICDs) are not well known.

HYPOTHESIS

The increasing number of ICD infections is related to accumulated pocket manipulations over time.

METHODS

This single-center, prospective study included patients that underwent ICD implantation from 2008 to 2015. The endpoint was time to infection. Multivariate analysis was performed to identify independent risk factors related to infection.

RESULTS

The study included a total of 570 patients, of whom 419 (73.5%) underwent a first implantation. Mean age was 59 ± 14 years, and 80% were male. During a median follow-up of 36 months (interquartile range, 18-61 months; 1887 patient-years), infection was identified in 26 patients (4.56%), an incidence of 14.9 × 1000 patient-years. Median time to infection was 9.7 months (interquartile range, 1.35-23.4 months), and 38.5% were late infections (beyond 12 months of follow-up). In patients with replacement implants, the incidence was 3-fold higher than in first implantations (27.7 vs 9.1 × 1000 patient-years; P = 0.002). Cox regression identified 2 independent predictors of ICD infection: cumulative number of interventions at the generator pocket (hazard ratio: 1.92, 95% confidence interval: 1.42-2.6, P < 0.001) and pocket hematoma (hazard ratio: 7.0, 95% confidence interval: 2.7-17.9, P < 0.0001).

CONCLUSIONS

The incidence of infection in ICD patients is greater than previously reported, largely due to late infections. Each new cumulative intervention at the same generator pocket nearly doubles the risk of infection.

Cardiac implantable electronic device infections: Who is at greatest risk?

BACKGROUND

Cardiac implantable electronic device (CIED) infections are associated with hospitalization, mortality, increased costs, and adverse outcomes.

OBJECTIVE

Determine the burden of infections for CIEDs based on device type, associated comorbidities, and clinical characteristics over a 12-year period.

METHODS

Utilizing data from the National Inpatient Sample database for cases from 2000 through 2012, we identified procedures for device-related infection (DRI) using International Statistical Classification of Diseases and Related Health Problems, Ninth Revision, Clinical Modification (ICD-9-CM) codes for CIED removal with diagnosis codes for device-related infection or systemic infection. Cases were categorized into 4 groups: single-chamber pacemaker, dual-chamber pacemaker, cardiac resynchronization therapy (CRT) device, and intracardiac defibrillator (ICD).

RESULTS

Of 4,144,683 device-related procedures, 85,203 (2.06%) were associated with DRI. From 2000 through 2012, procedures related to DRI increased from 1.45% to 3.41% (P < .001). The risk of infection for CRT devices was the highest, peaking in 2012 (adjusted odds ratio [OR] 2.43, P < .001). During second half of the study, comorbidities associated with DRI were diabetes (OR: 1.11, P < .001), end-stage renal disease (OR: 3.23, P < .001), hematoma (OR: 2.44, P < .001), malnutrition (OR: 2.66, P < .001), venous thromboembolism (OR: 2.37, P < .001), chronic kidney disease (OR: 1.26, P < .001), and organ transplantation (OR: 2.37, P < .001). Charges associated with CRT DRIs increased nearly 2-fold in a decade. Higher inpatient mortality related to device infection were stroke (OR: 3.19, P < .001), end-stage renal disease (OR: 2.91, P < .001), malnutrition (OR: 2.67, P < .001), cirrhosis (OR: 2.05, P = .001), and organ transplantation (OR: 2.16, P < .001).

CONCLUSION

CIED infections are increasing for all device types and particularly for CRT devices. Precise reasons for rising DRI procedures remain unclear, although conditions leading to immune compromise appear significant.

Cardiac implantable electronic devices in tracheotomized muscular dystrophy patients: Safety and risks

BACKGROUND/OBJECTIVES

Muscular dystrophies are genetic muscle disorders, in which heart involvement and chronic respiratory impairment affect survival. Cardiac conduction disturbances require implantable cardiac pacemaker. Implantable defibrillators may also be necessary to prevent cardiac sudden death. The safety and risk of cardiac electronic devices' implantation are not known in patients with muscular dystrophy. We aimed to assess the risks related to cardiac implantable electronic devices (CIED) in muscular dystrophy patients ventilated by tracheostomy.

METHODS

We reviewed all medical charts of neuromuscular patients and identified all CIED implantations of pacemakers (PM) or defibrillators (ICD) in patients ventilated using tracheostomy.

RESULTS

Twelve device implantations were included, performed in 9 patients (5 DMD, 1 Becker muscular dystrophy and 3 DM1). Mean age was 39.9years±13.0. All patients were wheel-chair bound and tracheotomized. Six pacemakers (PM) and 6 cardiac resynchronization (CRT) devices, including 2 defibrillators (CRT-D) were implanted. Following device implantation, two patients had a pneumothorax and one died from severe heart failure after an unsuccessful CRT implant attempt. Follow-up lasted up to 8years (mean 2.6±2.9years), during which one patient presented a PM pocket infection, requiring PM explantation and epicardial reimplantation.

CONCLUSION

We found a high prevalence of early complications (16.6% pneumothorax) after CIED implantation and an acceptable long-term infectious risk (8.3%). These results highlight the feasibility of CIED implantation in tracheotomized patients with muscular dystrophies and the need for a particular caution in the management of these patients during invasive procedures. ClinicalTrials.gov (identifier: NCT02501083).

A case of defibrillator-associated infective endocarditis due to Campylobacter fetus

Campylobacter spp. are Gram-negative, spiral motile bacteria. Infections caused by Campylobacter fetus are frequently of invasive character, but they are very rare. The described case of infection of a cardioverter defibrillator implantation site was effectively cured with antibiotics, but it required removal of the cardioverter defibrillator.

Cardiac Electrophysiology Laboratories: A Potential Target for Antimicrobial Stewardship and Quality Improvement?

BACKGROUND Infections following cardiovascular implantable electronic device (CIED) procedures, including pacemaker and implantable cardioverter-defibrillators, are devastating and costly. Preimplantation prophylactic antimicrobials are effective for reducing postprocedural infections. However, routine postprocedural antimicrobials are not associated with improved outcomes, and they may be harmful. Thus, we sought to characterize antimicrobial use patterns following CIED procedures. DESIGN All patients who underwent CIED procedures from October 1, 2007 to September 30, 2013 and had procedural information entered into the VA Clinical Assessment Reporting and Tracking (CART) software program were included in this study. All antibiotic prescriptions lasting more than 24 hours following device implantation or revision were identified using pharmacy databases, and postprocedural antibiotic use lasting more than 24 hours was characterized. RESULTS In total, 3,712 CIED procedures were performed at 34 VA facilities on 3,570 patients with a mean age of 71.7 years (standard deviation [SD], 11.1 years), 98.4% of whom were male. Postprocedural antibiotics >24 hours were prescribed following 1,579 of 3,712 CIED procedures (42.5%). The median duration of therapy was 5 days (interquartile range [IQR], 3-7 days). The most commonly prescribed antibiotic was cephalexin (1,152 of 1,579; 72.9%), followed by doxycycline (118 of 1,579; 7.47%) and ciprofloxacin (93 of 1,579; 5.9%). Vancomycin was used in 73 of 1,579 prescriptions (4.62%). Among the highest quartile of procedural volume, prescribing practices varied considerably, ranging from 3.2% to 77.6%. CONCLUSIONS Nearly 1 in 2 patients received prolonged postprocedural antimicrobial therapy following CIED procedures, and the rate of postprocedural antimicrobial therapy use varied considerably by facility. Given the lack of demonstrated benefit of routine prolonged antimicrobial therapy following CIED procedures, antimicrobial use following cardiac device interventions may be a potential target for quality improvement programs and antimicrobial stewardship. Infect Control Hosp Epidemiol 2016;37:1005-1011.

Cardiac Implantable Electronic Device Infection: From an Infection Prevention Perspective

A cardiac implantable electronic device (CIED) is indicated for patients with severely reduced ejection fraction or with life-threatening cardiac arrhythmias. Infection related to a CIED is one of the most feared complications of this life-saving device. The rate of CIED infection has been estimated to be between 2 and 25; though evidence shows that this rate continues to rise with increasing expenditure to the patient as well as healthcare systems. Multiple risk factors have been attributed to the increased rates of CIED infection and host comorbidities as well as procedure related risks. Infection prevention efforts are being developed as defined bundles in numerous hospitals around the country given the increased morbidity and mortality from CIED related infections. This paper aims at reviewing the various infection prevention measures employed at hospitals and also highlights the areas that have relatively less established evidence for efficacy.

Safety and feasibility of biventricular devices reuse in general and elderly population--a single-center retrospective cohort study

Introduction

Cardiac resynchronization therapy (CRT) is known to have very important beneficial effects on heart failure patients. Unfortunately, biventricular implantable cardiac devices (CRT devices), through which this therapy is implemented, are very expensive and sometimes hard to achieve, especially in underdeveloped/developing economies, making this an important problem of public health. As a possible solution, CRT reuse is of great interest nowadays, but unlike simple devices, data in the literature are scarce about biventricular device reuse.

Aim

To address safety concerns, we aimed to analyze infection burden in the general and elderly population and also early battery depletion and generator malfunction of resterilized biventricular devices compared to new devices.

Methods

A cohort of 261 CRT patients (286 devices), who underwent implantation between 2000 and 2014, was retrospectively analyzed. The study group included 115 patients and 127 resterilized devices, that was divided into a subgroup of 69 elderly patients (≥60 years) and 74 devices and a subgroup of 47 younger patients (<60 years) and 53 devices, and the control group included 146 patients and 159 new devices. The groups were compared using a multivariate logistic regression model.

Results

A number of 12 (4.2%) infectious complications were encountered, five (3.9%) in the study group and seven (4.4%) in the control group (odds ratio, 2.83 [0.59–13.44], P=0.189), one (1.3%) in the elderly and four (7.5%) in the younger subgroup (odds ratio, 3.80 [0.36–40.30], P=0.266), with no statistically significant difference between them. There was only one case of early battery depletion, after 17 months, in one study group patient. No generator malfunction was detected.

Conclusion

Reuse of biventricular cardiac implantable electronics seems feasible and safe in both the general population and the elderly population, and it could be a promising alternative when new devices cannot be obtained in a safe period of time.

Lead-Dependent Infective Endocarditis: The Role of Factors Predisposing to Its Development in an Analysis of 414 Clinical Cases

BACKGROUND

Lead-dependent infective endocarditis (LDIE) is a serious and insidious infective disease spreading along the leads to valve leaflets and endocardial surface. LDIE is still a lesser known disease with unclear risk factors, most often evaluated jointly for all infectious complications.

METHODS

Clinical data from 414 patients with the diagnosis of LDIE according to the Modified Duke Leads Criteria were analyzed. Patients with LDIE were identified in a population of 1,426 subjects submitted to transvenous lead extraction (TLE) in the Reference Center on Lead Extraction in Lublin, Poland, between March 2006 and July 2013 due to infectious (619 patients-43.4%) and noninfectious (807-56.6% of patients) reasons. During the period of 2006-2011, the analysis was conducted retrospectively; from early 2012 on, patients were enrolled prospectively. The effect of potential risk factors on the development of the disease was evaluated in a comparative analysis of clinical data from the LDIE patients and from 807 subjects with noninfectious indications for TLE. Additionally, in order to identify the factors predisposing to the development of LDIE, the population of infectious patients was divided into three subgroups: with isolated LDIE (157 patients), with LDIE and pocket infection (PI; 257 patients), and with isolated PI (205 patients). The groups and subgroups were analyzed for the presence of patient-dependent risk factors (age, gender, accompanying diseases, anticoagulation, or antiplatelet therapy) and procedure-related risk factors (the number and lead dwell time, pacing system, prior procedures, lead loops, and intracardiac abrasion of the leads). Furthermore, microbes' identification was conducted.

RESULTS

The LDIE patients were older (67.3 vs 62.3; P = 0.001) and were more frequently male (68.6% vs 55.0%; P = 0.001) as compared with patients submitted to TLE for noninfectious reasons, but not in comparison with subjects diagnosed with isolated LDIE. In univariate analysis, the independent prognostic factors of LDIE were: type 2 diabetes-increase of risk by 37.7% (hazard ratio [HR] = 1,377; 95% confidence interval [CI] [1,088-1,742]), elevated above 2 mg% creatinine level-increase of risk by 61.5% (HR = 1,615; 95% CI [1,96-2,182]), antiplatelet therapy (HR = 1,285; 95% CI [1,052-1,057]), number of intracardiac leads prior to TLE (HR = 1,199; 95% CI [1,075-1,337]), intracardiac device with implantable cardioverter defibrillator (ICD) lead (HR = 1,909; 95% CI [1,492-2,444]), intracardiac device with coronary sinus lead (HR = 1,411; 95% CI [1,099-1,810]), number of procedures prior to TLE (HR = 1,092; 95% CI [1,017-1,172]), and abrasion of intracardiac leads (HR = 1,350; 95% CI [1,097-1,662]). Multivariate logistic regression demonstrated that the independent risk factors of LDIE were: chronic renal failure (HR = 1,406; 95% CI [1,033-1,915]), number of intracardiac leads prior to TLE (HR = 1,152; 95% CI [1,017-1,305]), intracardiac devices with ICD leads (HR = 1,719; 95% CI [1,330-2,223]), and presence of abrasion of intracardiac leads (HR = 1,405; 95% CI [1,129-1,750]). Microbiological analysis showed the domination of coagulase-negative staphylococci with relative advantage of Staphylococcus epidermidis in pathogenesis of LDIE.

CONCLUSIONS

The factors predisposing to LDIE are mainly related to procedures performed on the patients. LDIE develops more frequently in patients with multiple leads, especially ICD. An important, until now lesser known, risk factor for LDIE is intracardiac abrasion of the leads strongly connected with procedural agents and properties of specific kind of bacteries. A new concept of the pathogenesis of LDIE was proposed on the basis of present analysis.

Rates of and Factors Associated With Infection in 200 909 Medicare Implantable Cardioverter-Defibrillator Implants

Background—

The rate of implantable cardioverter-defibrillator (ICD) infections has been increasing faster than that of implantation. We sought to determine the rate and predictors of ICD infection in a large cohort of Medicare patients.

Methods and Results—

Cases submitted to the ICD Registry from 2006 to 2009 were matched to Medicare fee-for-service claims data using indirect patient identifiers. ICD infections occurring within 6 months of hospital discharge after implantation were identified by ICD-9 codes. Logistic regression was used to examine factors associated with risk of ICD infection. Of 200 909 implants, 3390 patients (1.7%) developed an ICD infection. The infection rate was 1.4%, 1.5%, and 2.0% for single, dual, and biventricular ICDs, respectively ( P <0.001). Generator replacement had a higher rate compared with initial implant (1.9% versus 1.6%, P <0.001). The factors associated with infection were adverse event during implant requiring reintervention (odds ratio [OR], 2.692; 95% confidence interval [CI], 2.304–3.145), previous valvular surgery (OR, 1.525; 95% CI, 1.375–1.692), reimplantation for device upgrade, malfunction, or manufacturer advisory (OR, 1.354; 95% CI, 1.196–1.533), renal failure on dialysis (OR, 1.342; 95% CI, 1.123–1.604), chronic lung disease (OR, 1.215; 95% CI, 1.125–1.312), cerebrovascular disease (OR, 1.172; 95% CI, 1.076–1.276), and warfarin (OR, 1.155; 95% CI, 1.060–1.257).

Conclusions—

Patients who developed an ICD infection were more likely to have had peri-ICD implant complications requiring early reintervention, previous valve surgery, device replacement for reasons other than battery depletion, and increased comorbidity burden. Efforts should be made to carefully consider when to reenter the pocket at any time other than battery replacement.

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.

Risk factors and prognosis for clot formation on cardiac device leads

BACKGROUND

Clot formation on cardiac device leads is poorly understood. We sought to determine how often clot is seen on device leads by transthoracic echo (TTE), identify risk factors, and to describe the natural history of this phenomenon.

METHODS

We reviewed 71,888 echocardiographic studies performed at the University of California, San Francisco from 2005 to 2011. We searched for cases where clot was found adhered to a device lead with no diagnosis of endocarditis. For every case, three age-matched controls with a device but no clot were selected from the echo database.

RESULTS

We found 15 cases with clot adhered to a device lead among 1,086 patients with devices who had TTE (1.4%). In univariate analysis, females had more than four times greater odds of having a clot on their device lead and patients with a history of atrial fibrillation (AF) had an eight times greater odds. Percentage mode switch was also associated with clot formation. Only AF was still associated with clot formation after multivariate analysis. Follow-up data were available for nine of 15 patients. All nine patients had intensification of their anticoagulant/antiplatelet regimen following clot discovery. Complete resolution or shrinkage of clot was observed in eight of nine patients. The one case with no change was a patient who continued taking only aspirin (higher dose) after clot discovery. None of the nine patients had embolic phenomenon.

CONCLUSION

Patients with AF are at higher risk for clot formation on device leads. After clot detection, treatment with anticoagulants usually results in resolution of the clot without embolic phenomenon.