Variability in clinical features of early versus late cardiovascular implantable electronic device pocket infections

Risk factors associated with higher mortality in patients with cardiac implantable electronic device infection

INTRODUCTION

Cardiac Implantable Electronic Devices (CIEDs) are widely used for the management of advanced heart failure and ventricular arrhythmias. CIED-Infection (CIED-I) has very high mortality, especially in the subsets of patients with limited health-care access and delayed presentation. The purpose of this study is to identify the risk-predictors mortality in subjects with CIED-I.

METHODS

We performed a retrospective cohort study of a regional database in patients presenting with CIED infections to tertiary care medical centers across Western New York, USA from 2012 to 2020. The clinical outcomes included recurrent device infection (any admission for CIED-I after the first hospitalization for device infection), septic complications (pulmonary embolism, respiratory failure, septic shock, decompensated HF, acute kidney injury) and mortality outcomes (death during hospitalization, within 30 days from CIED-I, and within 1 year from CIED-I). We studied associations between categorical variables and hard outcomes using χ2 tests and used one-way analysis of variance to measure between-groups differences.

RESULTS

We identified 296 patients with CIED-I, among which 218 (74%) were male, 237 (80%) were white and the mean age at the time of infection was 69.2 ± 13.7 years. One-third of the patients were referred from the regional facilities. Staphylococcus aureus was responsible for most infections, followed by Enterococcus fecalis. On multivariate analysis, the covariates associated with significantly increased mortality risk included referral from regional facility (OR: 2.0;1.0-4.0), hypertension (Odds ratio, OR: 3.2;1.3-8.8), right ventricular dysfunction (OR: 2.6;1.2-5.1), end-stage renal disease (OR: 2.6;1.1-6.2), immunosuppression (OR: 11.4;2.5-53.3), and septic shock as a complication of CIED-I (OR: 3.9;1.3-10.8).

CONCLUSION

Hypertension, right ventricular dysfunction, immunosuppression, and end-stage renal disease are associated with higher mortality after CIED-I. Disproportionately higher mortality was also noted in subjects referred from the regional facilities. This underscores the importance of early clinical risk-assessment, and the need for a robust referral infrastructure to improve patient outcomes.

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].

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.

Early, Delayed and Late Cardiac Implantable Electronic Device Infections: Do the Timing of Onset and Pathogens Matter?

Infections involving cardiac implantable electronic devices (CIEDs) occur at different times after device-related procedures. The aim of this study was to investigate the timing of onset and factors influencing the occurrence of all types of CIED infections to identify the type of pathogen and to examine the long-term survival of patients with all types of CIED infections. We performed a post hoc analysis of the clinical data from 3344 patients who underwent transvenous lead extraction (TLE) at a single high-volume center between 2006 and 2020, including a group of 890 patients with CIED infections. The occurrence of pocket infection (PI), lead-related infective endocarditis (LRIE) and PI coexisting with LRIE (PI + LRIE) was assessed at the following time intervals: 0−12 months, 13−36 months and > 36 months since last CIED-related procedure. In the study group, there were 274 (30.79%) early infections, 266 (29.89%) delayed infections and 350 (39.32%) late infections. Pocket infection was the most common early complication (97; 39.43%), while LRIE was predominant over 36 months from the last CIED procedure (172; 54.09%). The most common early infections were PIs that were associated with the preceding CIED-related procedure. Late LRIE was most likely to occur in patients with intracardiac lead abrasion. The probability of early versus late LRIE was higher in patients with CoNS cultures. The timing of infection onset irrespective of its type does not affect long-term survival after transvenous lead extraction. The majority of infectious complications (69%) occur more than 12 months after the last CIED-related procedure. Early infections are probably associated with pocket contamination during CIED-related procedure, while delayed and late systemic infections are related to other lead-dependent factors (especially to intracardiac lead abrasion). Time to LRIE onset is associated with pathogen type. The timing of symptom onset does not affect long-term survival after TLE.

Echocardiography and FDG-PET/CT scan in Gram-negative bacteremia and cardiovascular infections

PURPOSE OF REVIEW

Current evidence on cardiovascular infections in Gram-negative blood stream infections (GNBSI) with focus on the use of transesophageal echocardiography (TEE) and 18F-Fluorodeoxyglucose - positron emission tomography/Computed tomography (FDG-PET/CT) in the diagnostic workup.

RECENT FINDINGS

Most evidence focuses on characteristics of diagnosed cardiovascular infections and the proportion caused by GNBSI. These proportions are low (1-5%) when it comes to native and prosthetic valve endocarditis as well as cardiac implantable electronic device (CIED) infections whereas the proportion of vascular graft infections caused by GNBSI seems substantially higher (30-40%). Information on the prevalence of cardiovascular infection in patients with GNBSI is limited to a few studies finding around 3% endocarditis in patients with GNBSI and a prosthetic heart valve and 4-16% device-related infection in patients with CIED and GNBSI.

SUMMARY

Patients with GNBSI and native or prosthetic valves should only undergo work-up for endocarditis (TEE and FDG-PET/CT) if they present GNBSI relapse or signs suggestive of endocarditis. CIED patients with GNBSI with Pseudomonas or Serratia spp. should undergo TEE and PET/CT because of the high prevalence of device-related infection. In other GNBs without IE suggestive signs, normal BSI treatment is reasonable and only cases with relapse need work-up. GNBSI in patients with vascular grafts should lead to consideration of PET/CT.

Clinical utility of sonication for diagnosing infection and colonization of cardiovascular implantable electronic devices

Our study aimed to evaluate the sensitivity of the sonication tool for the microbiological diagnosis of cardiovascular implantable electronic device infections (CIEDIs). The extracted cardiac implants of 52 patients were assessed: 19 with CIEDI and 33 with elective generator replacement or revision without clinical infection. Sonication fluid culture of explanted CIEDs yielded higher numbers of microorganisms than pocket tissue or swab cultures. The sensitivity of sonication fluid culture was significantly higher than that of pocket swab and tissue culture for microbiological diagnosis of CIEDI. The microorganisms isolated most frequently via sonication of explanted CIEDs were Gram-positive cocci (70%), of which 50% was coagulase-negative Staphylococcus. Sonication fluid culture detected colonization in 36.4% of the non-infected patients. Sonication fluid culture represents a promising diagnostic strategy with increased sensitivity compared to conventional culture methods for microbiological diagnosis of cardiac devices associated with infection and colonization.

The emergence of Staphylococcus aureus as the primary cause of cardiac device-related infective endocarditis

BACKGROUND

Increasing use of cardiovascular implantable electronic devices (CIED), as permanent pacemakers (PPM), implantable cardioverter defibrillators (ICD), or cardiac resynchronization therapy (CRT), is associated with the emergence of CIED-related infective endocarditis (CIED-IE). We aimed to characterize CIED-IE profile, temporal trends, and prognostic factors.

METHODS

CIED-IE diagnosed at Rennes University Hospital during years 1992-2017 were identified through computerized database, and included if they presented all of the following: (1) clinical signs of infection; (2) microbiological documentation through blood and/or CIED lead cultures; (3) lead or valve vegetation, or definite IE according to Duke criteria. Data were retrospectively extracted from medical charts. The cohort was categorized in three periods: 1992-1999, 2000-2008, and 2009-2017.

RESULTS

We included 199 patients (51 women, 148 men, median age 73 years [interquartile range, 64-79]), with CIED-IE: 158 PPMs (79%), 24 ICD (12%), and 17 CRT (9%). Main pathogens were coagulase-negative staphylococci (CoNS: n = 86, 43%), Staphylococcus aureus (n = 60, 30%), and other Gram-positive cocci (n = 28, 14%). Temporal trends were remarkable for the decline in CoNS (P = 0.002), and the emergence of S. aureus as the primary cause of CIED-IE (24/63 in 2009-2017, 38%). Factors independently associated with one-year mortality were chronic obstructive pulmonary disease (COPD: hazard ratio 3.84 [1.03-6.02], P = 0.03), left-sided endocarditis (HR 2.25 [1.09-4.65], P = 0.03), pathogens other than CoNS (HR 3.16 [1.19-8.39], P = 0.02), and CIED removal/reimplantation (HR 0.41 [0.20-0.83], P = 0.01).

CONCLUSIONS

S. aureus has emerged as the primary cause of CIED-IE. Left-sided endocarditis, COPD, pathogens other than CoNS, and no CIED removal/reimplantation are independent risk factors for one-year mortality.

Antibiotic Prophylaxis and Treatment in Early Cardiac Implantable Electronic Devices Infection

Background

Cardiac implantable electronic devices - PM, ICD, and CRTs- are well-proven life-sustaining and the ultimate destination for many heart conditions. Based on scientific evidence, there is a worldwide incremental increase in CIED implantations numbers.

Objective

Early infection of cardiac implantable electronic devices (CIED)- pacemaker (PM), implantable cardioverter-defibrillator (ICD), and cardiac resynchronization therapy (CRT)- is a growing health challenge. We examined the effectiveness of antibiotic prophylaxis and treatment of early infection of CIED in a single center.

Methods

This is a retrospective, single-center observational study. Data were collected from patients' records from July 2017-July, 2019. All Patients received intravenous ceftriaxone 2gm before incision, Gentamicin 120mg pocket irrigation, and oral Amoxicillin/Clavulanate for 5 days post-implantation.

Results

A 639 consecutive CIED implantations - PM (n=474, mean age, 64yr, female=49%), ICD (n=106, mean age 56yr, female=17%) and CRT (n=59, mean age, 54yr, female=20%)- were performed over 3years. The incidence of early infection was 1.9% (12 cases), female=41%. PM=5/474, ICD=5/106, and CRT=2/59. Three out of the 12 patients had total device explant due to pocket abscess; one PM had a generator changed; one ICD who had a pneumothorax, and the third one had reimplantation after ICD lead perforation. Nine cases were managed conservatively using saline dressing and oral Amoxicillin/Clavulanate, 3/9 patients developed a hematoma, 4/9 patients developed purulent suture line infection. None of them had infection recurrence on three months follow up.

Conclusion

Early infection of CIED is a rare complication with multiple predisposing factors. Our protocol is reassurance and prompt initiation of management protocol to prevent and treat this issue's sequences.

Usefulness of 18F-FDG PET/CT in Patients with Cardiac Implantable Electronic Device Suspected of Late Infection

The presence of a cardiovascular implantable electronic device (CIED) can be burdened by complications such as late infections that are associated with significant morbidity and mortality and require immediate and effective treatment. The aim of this study was to evaluate the role of ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT) in patients with suspected CIED infection. Fifteen patients who performed a ¹⁸F-FDG PET/CT for suspicion of CIED infection were retrospectively analyzed; 15 patients, with CIED, that underwent ¹⁸F-FDG PET/CT for oncological reasons, were also evaluated. Visual qualitative analysis and semi-quantitative analysis were performed. All patients underwent standard clinical management regardless ¹⁸F-FDG PET/CT results. Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) resulted as 90.91%, 75%, 86.67%, 90.91% and 75% respectively. Maximum standardized uptake values (SUV_max) and semi-quantitative ratio (SQR) were collected and showed differences statistically significant between CIED infected patients and those who were not. Exploratory cut-off values were derived from receiver operating characteristic (ROC) curves for SUV_max (2.56) and SQR (4.15). This study suggests the clinical usefulness of ¹⁸F-FDG PET/CT in patients with CIED infection due to its high sensitivity, repeatability and non-invasiveness. It can help the clinicians in decision making, especially in patients with doubtful clinical presentation. Future large-scale and multicentric studies should be conducted to establish precise protocols about ¹⁸F-FDG PET/CT performance.

Lead extraction for reduction of chronic pain related to cardiovascular implantable electronic device

AIMS

Chronic pain at the cardiovascular implantable electronic device (CIED) generator or lead insertion site that is not otherwise manageable carries a IIA indication for extraction. However, limited data exist evaluating causes of pain and outcomes of extraction in eliminating pain. A multi-centre retrospective observational study was conducted to evaluate outcomes of patients undergoing device extraction for treatment of chronic device pain.

METHODS AND RESULTS

Twenty-seven out of 2188 lead extraction candidates (1.3%) met the chronic pain IIA indication for extraction [50 ± 16 years; 14 (51%) women]. Onset, severity, triggers, and pain management were measured before and after extraction. Device type, procedure done (with/without reimplantation), and positive tissue cultures were noted. Pain was reported as constant (n = 14; 50%), intermittent (n = 13; 46%), and movement-triggered (n = 14; 50%). Average severity of pain was seven out of 10 (10 being the worst). Post-extraction, 18 (66%) received freedom from pain, including all patients with poorly formed pockets (n = 2) and subclinical infections (n = 2). Of the 18, 11 underwent reimplantation (61%) without recurrent pain. Nine still had pain (44 ± 17 years; seven women) after extraction. Eight of the nine underwent reimplantation, three on the contralateral chest wall and five ipsilaterally. Pain severity decreased (n = 5), increased (n = 1), or was unchanged (n = 3).

CONCLUSION

Chronic pain at the CIED generator site can present as chronic or movement-triggered pain, and can be due to subclinical infection or a poorly formed device pocket. Extraction relieved constant and intermittent pain in two-thirds of patients. Extraction appears less successful in eliminating pain in women who undergo subsequent reimplantation.

The predictors and economic burden of early-, mid- and late-onset cardiac implantable electronic device infections: a retrospective cohort study in Ontario, Canada

The rate of cardiac implantable electronic device (CIED) infection is increasing with time. We sought to determine the predictors, relative mortality, and cost burden of early-, mid- and late-onset CIED infections. We conducted a retrospective cohort study of all CIED implantations in Ontario, Canada between April 2013 and March 2016. The procedures and infections were identified in validated, population-wide health-care databases. Infection onset was categorized as early (0-30 days), mid (31-182 days) and late (183-365 days). Cox proportional hazards regression was used to assess the mortality impact of CIED infections, with infection modelled as a time-varying covariate. A generalized linear model with a log-link and γ distribution was used to compare health-care system costs by infection status. Among 17 584 patients undergoing CIED implantation, 215 (1.2%) developed an infection, including 88 early, 85 mid, and 42 late infections. The adjusted hazard ratio (aHR) of death was higher for patients with early (aHR 2.9, 95% CI 1.7-4.9), mid (aHR 3.3, 95% CI 1.9-5.7) and late (aHR 19.9, 95% CI 9.9-40.2) infections. Total mean 1-year health costs were highest for late-onset (mean Can$113 778), followed by mid-onset (mean Can$85 302), and then early-onset (Can$75 415) infections; costs for uninfected patients were Can$25 631. After accounting for patient and procedure characteristics, there was a significant increase in costs associated with early- (rate ratio (RR) 3.1, 95% CI 2.3-4.1), mid- (RR 2.8, 95% CI 2.4-3.3) and late- (RR 4.7, 95% CI 3.6-6.2) onset infections. In summary, CIED infections carry a tremendous clinical and economic burden, and this burden is disproportionately high for late-onset infections.

Predictors of Bloodstream Infection in Patients Presenting With Cardiovascular Implantable Electronic Device Pocket Infection

Background

Generator pocket infection is the most frequent presentation of cardiovascular implantable electronic device (CIED) infection. We aim to identify predictors of underlying bloodstream infection (BSI) in patients presenting with CIED pocket infection.

Methods

We retrospectively reviewed all adults with CIED pocket infection cared for at our institution from January 2005 through January 2016. The CIED pocket infection cases were then subclassified as with or without associated BSI. Variables with P values <.05 at univariate analysis were included in a multivariable model to identify independent predictors of underlying BSI.

Results

We screened 429 cases of CIED infection, and 95 met the inclusion criteria. Of these, 68 cases (71.6%) were categorized as non-BSI and 27 (28.4%) as BSI. There were no statistically significant differences in patient comorbid conditions or device characteristics between the 2 groups. In multivariable analysis, the presence of systemic inflammatory response syndrome criteria (tachycardia, tachypnea, fever or hypothermia, and leukocytosis or leukopenia) and hypotension were independent predictors of underlying BSI in patients presenting with CIED pocket infection. Overall, patients in the non-BSI group who did not receive pre-extraction antibiotics had a higher frequency of positive intraoperative pocket/device cultures than those with pre-extraction antibiotic exposure (79.4% vs 58.6%; P = .06).

Conclusions

Patients with CIED pocket infection who meet systemic inflammatory response syndrome criteria and/or are hypotensive at admission are more likely to have underlying BSI and should be started on empiric antibiotics after blood cultures are obtained. If these features are absent, it may be reasonable to withhold empiric antibiotics to optimize yield of pocket/device cultures during extraction.

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

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

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.

Hypoglossal nerve stimulator generator migration: INSPIRE device reimplantation with parallels to cardiac implantable electronic devices

Implantation rates of hypoglossal nerve stimulators, such as INSPIRE, are increasing. The device is still in its early stages of complication reporting, which to date includes implant related infection requiring device removal, and stimulation lead cuff dislodgement requiring replacement. Here we present a 48-year-old female who experienced generator migration and stimulator lead tension requiring an additional operation in order to resecure the generator device. This proved unsuccessful and a second surgery was performed with complete relocation of the device generator to inhibit device migration. This is the first documented case of INSPIRE migration to date, though the implant generator has comparable likeness to cardiovascular implantable electronic devices (CIEDs) where migration risk factors are better studied. Given our patient's case, we identify obesity and abundant breast tissue as potential risk factors for device migration. We believe such factors can be identified prior to initial device implantation to avoid migration and the need for surgical revision. Superior positioning of the generator proved successful, and can be a solution in those with similar body habitus as TYRX pouching and additional security sutures were ineffective. Also, for revisions requiring tunneling of the stimulation lead as in this case we recommend the use of zero degree endoscope for ease of adhesion lysis.

Impact of Abandoned Leads on Cardiovascular Implantable Electronic Device Infections: A Propensity Matched Analysis of MEDIC (Multicenter Electrophysiologic Device Infection Cohort)

OBJECTIVES

This study sought to evaluate the impact of abandoned cardiovascular implantable electronic device (CIED) leads on the presentation and management of device-related infections.

BACKGROUND

Device infection is a serious consequence of CIEDs and necessitates removal of all hardware for attempted cure. The merits of extracting or retaining presumed sterile but nonfunctioning leads is a subject of ongoing debate.

METHODS

The MEDIC (Multicenter Electrophysiologic Device Infection Cohort) prospectively enrolled patients with CIED infections at 10 institutions in the United States and abroad between January 1, 2009, and December 31, 2012. Within a propensity-matched cohort, relevant clinical information was compared between patients who had 1 or more abandoned leads at the time of infection and those who had none.

RESULTS

Matching produced a cohort of 264 patients, including 176 with no abandoned leads and 88 with abandoned leads. The groups were balanced with respect to Charlson comorbidity index, oldest lead age, device type, sex, and race. At the time of admission, those with abandoned leads were less likely to demonstrate systemic signs of infection, including leukocytosis (p = 0.023) and positive blood cultures (p = 0.005). Conversely, patients with abandoned leads were more likely to demonstrate local signs of infections, including skin erosion (p = 0.031) and positive pocket cultures (p = 0.015). In addition, patients with abandoned leads were more likely to require laser extraction (p = 0.010).

CONCLUSIONS

The results of a large prospective registry of CIED infections demonstrated that patients with abandoned leads may present with different signs, symptoms, and microbiological findings and require laser extraction more than those without abandoned leads.

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

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

Technologies for Prolonging Cardiac Implantable Electronic Device Longevity

Prolonged longevity of cardiac implantable electronic devices (CIEDs) is needed not only as a passive response to match the prolonging life expectancy of patient recipients, but will also actively prolong their life expectancy by avoiding/deferring the risks (and costs) associated with device replacement. CIEDs are still exclusively powered by nonrechargeable primary batteries, and energy exhaustion is the dominant and an inevitable cause of device replacement. The longevity of a CIED is thus determined by the attrition rate of its finite energy reserve. The energy available from a battery depends on its capacity (total amount of electric charge), chemistry (anode, cathode, and electrolyte), and internal architecture (stacked plate, folded plate, and spiral wound). The energy uses of a CIED vary and include a background current for running electronic circuitry, periodic radiofrequency telemetry, high-voltage capacitor reformation, constant ventricular pacing, and sporadic shocks for the cardiac resynchronization therapy defibrillators. The energy use by a CIED is primarily determined by the patient recipient's clinical needs, but the energy stored in the device battery is entirely under the manufacturer's control. A larger battery capacity generally results in a longer-lasting device, but improved battery chemistry and architecture may allow more space-efficient designs. Armed with the necessary technical knowledge, healthcare professionals and purchasers will be empowered to make judicious selection on device models and maximize the utilization of all their energy-saving features, to prolong device longevity for the benefits of their patients and healthcare systems.

Incidence, Treatment Intensity, and Incremental Annual Expenditures for Patients Experiencing a Cardiac Implantable Electronic Device Infection

Background—

Because of the increasing use of cardiac implantable electronic devices (CIEDs), it is important to estimate the incidence and annual healthcare expenditures associated with CIED infections.

Methods and Results—

Patients with a record of an initial or replacement (full implant or generator only) CIED implant during the calendar years 2009 to 2012 in MarketScan Commercial Claims and Medicare Supplemental database were identified. CIED infections were classified into 4 categories: (1) infection not managed by inpatient admission nor implant removal, (2) infection managed by inpatient admission but no implant removal, (3) infection managed by an implant removal either in an inpatient or in an outpatient setting, and (4) infection with severe sepsis and managed in an inpatient setting with implant removal. Using separate models for initial and replacement cohorts, annualized incidence of infection and incremental annual expenditures by treatment intensity were estimated. Cumulative incidence of infection at 1 year post implant was 1.18% for initial CIED implants and 2.37% for replacement. Median time to infection was 35 days for initial and 23 days for replacement. Incremental healthcare expenditures by treatment intensity categories for initial implant patients at 1 year were $16 651, $104 077, $45 291, and $279 744. For replacement patients, incremental expenditures at 1 year by treatment intensity categories were $26 857, $43 541, $48 759, and $362 606.

Conclusions—

The management of CIED infections results in a substantial healthcare burden with a significant increase in annual expenditures the year after implant when device infection occurs.

Microbial diagnosis of infection and colonization of cardiac implantable electronic devices by use of sonication

OBJECTIVES

The clinical utility of sonication as an adjunctive diagnostic tool for the microbial diagnosis of cardiac implantable device-associated infections (CIDAIs) was investigated.

METHODS

The implants of 83 subjects were investigated, 15 with a CIDAI and 68 without a clinical infection. Clinical data were analyzed prospectively and sonication fluid cultures (83 patients, 100%) and traditional cultures (31 patients, 37.4%) were performed

RESULTS

Generator pocket infection and device-related endocarditis were found in 13 (86.7%) and four (26.7%) subjects, respectively. The mean numbers of previous technical complications and infections were higher in the infected patients compared to the non-infected patients (8 vs. 1, p<0.001; 2 vs. 0, p<0.031, respectively). The sensitivity and specificity for detecting CIDAI was 73.3% (11/15) and 48.5% (33/68) for sonication fluid culture, and 26.7% (4/15) and 100% (16/16) for traditional culture (p<0.001), respectively. A higher number of organisms were identified by sonication fluid than by tissue culture (58 vs. 4 specimens; p<0.001). The most frequent organisms cultured were Gram-positive cocci (66.1%), mainly coagulase-negative staphylococci (35.5%). Thirty-five (51.5%) non-infected subjects were considered colonized due to the positive identification of organisms exclusively through sonication fluid culture.

CONCLUSIONS

Sonication fluid culture from the removed cardiac implants has the potential to improve the microbiological diagnosis of CIDAIs.

Management of Cardiovascular Implantable Electronic Devices Infections in High-Risk Patients

The incidence of infection following implantation of cardiovascular implantable electronic devices (CIEDs) is increasing, as is the number of pulse generator replacements and upgrades. The rate of infections is rising faster than the rate of device implantation, mainly due to the increasing age and number of comorbidities of patients receiving the devices. Patients with a CIED infection usually require hospitalisation, multiple consultations, prolonged intravenous antibiotics and, in the majority of cases, CIED explantation and replacement. A significant proportion die of their infection. CIED infection therefore represents a substantial health and economic burden, and management of infections is critical. Numerous risk factors have been identified including host, procedure and device-related factors. Established strategies for preventing CIED infections include intravenous antibiotics and aseptic techniques. The TYRX™ Absorbable Antibacterial Envelope offers potential as an effective method to reduce CIED infections. Several studies have found a statistically significant association between antibacterial envelope use and reduced incidence of CIED infection in high-risk patients. A prospective, randomised trial to further evaluate this potentially important strategy for CIED infection prophylaxis is underway.