Diagnosis of Cardiac Device–Related Infective Endocarditis After Device Removal

Role of echocardiography in the diagnosis and clinical management of infective endocarditis

Infective endocarditis (IE) is a deadly disease, constituting both diagnostic and treatment challenges. A positive outcome requires rapid and accurate diagnosis, and for that, echocardiography unequivocally remains the cornerstone. Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) have complementary roles and have been markedly improved during the last decades. The transthoracic modality is the recommended first-line approach but may only be sufficient in patients where the probability of IE is low and/or with clear acoustic windows, especially in patients with right-sided IE. The transesophageal modality is superior to TTE in most aspects and is recommended for all other patients. Both TTE and TEE may delineate vegetation location and size, assess for paravalvular extension of infection, and have the added advantage of defining the hemodynamic effects of valvular or device infection. However, echocardiography still has significant limitations, and novel imaging techniques are increasingly being exploited to improve diagnostic potential. Cardiac computed tomography (CT) performs better than TEE in the detection of abscess or pseudoaneurysm, while magnetic resonance imaging (MRI) has limited value in the diagnostic phase of IE but adds knowledge to the evaluation of extracardiac events. Nuclear molecular techniques are evolving as key supplementary methods in difficult-to-diagnose cases. Although newer imaging modalities are undergoing preliminary evaluation and multimodal imaging will play an increasing role in IE, echocardiography will continue to be pivotal in patients with IE for the foreseeable future.

Novel dalbavancin-PLLA implant coating prevents hematogenous Staphylococcus aureus infection in a minimally invasive mouse tail vein model

Infective/bacterial endocarditis is a rare but life-threatening disease with a hospital mortality rate of 22.7% and a 1-year mortality rate of 40%. Therefore, continued research efforts to develop efficient anti-infective implant materials are of the utmost importance. Equally important is the development of test systems that allow the performance of new materials to be comprehensively evaluated. In this study, a novel antibacterial coating based on dalbavancin was tested in comparison to rifampicin/minocycline, and the suitability of a recently developed mouse tail vein model for testing the implant coatings was validated. Small polymeric stent grafts coated with a poly-L-lactic acid (PLLA) layer and incorporated antibiotics were colonized with Staphylococcus (S.) aureus before implantation into the tail vein of mice. The main assessment criteria were the hematogenous spread of the bacteria and the local tissue reaction to the contaminated implant. For this purpose, colony-forming units (CFU) in the blood, spleen and kidneys were determined. Tail cross sections were prepared for histological analysis, and plasma cytokine levels and expression values of inflammation-associated genes were examined. Both antibiotic coatings performed excellently, preventing the onset of infection. The present study expands the range of available methods for testing the anti-infectivity of cardiovascular implants, and the spectrum of agents for effective surface coating.

"Ghost", a Well-Known but Not Fully Explained Echocardiographic Finding during Transvenous Lead Extraction: Clinical Significance

"Ghosts" are fibrinous remnants that become visible during transvenous lead extraction (TLE).

METHODS

Data from transoesophageal echocardiography-guided TLE procedures performed in 1103 patients were analysed to identify predisposing risk factors for the development of so-called disappearing ghosts-flying ghosts (FG), or attached to the cardiovascular wall-stable ghosts (SG), and to find out whether the presence of ghosts affected patient prognosis after TLE.

RESULTS

Ghosts were detected in 44.67% of patients (FG 15.5%, SG 29.2%). The occurrence of ghosts was associated with patient age at first system implantation [FG (OR = 0.984; p = 0.019), SG (OR = 0.989; p = 0.030)], scar tissue around the lead (s) [FG (OR = 7.106; p < 0.001, OR = 1.372; p = 0.011), SG (OR = 1.940; p < 0.001)], adherence of the lead to the cardiovascular wall [FG (OR = 0.517; p = 0.034)] and the number of leads [SG (OR = 1.450; p < 0.002). The presence of ghosts had no impact on long-term survival after TLE in the whole study group [FG HR = 0.927, 95% CI (0.742-1.159); p = 0.505; SG HR = 0.845, 95% CI (0.638-1.132); p = 0.265].

CONCLUSIONS

The degree of growth and maturation of scar tissue surrounding the lead was the strongest factor leading to the development of both types of ghosts. The presence of either form of ghost did not affect long-term survival even after TLE indicated for infection.

Best Practices for Imaging Cardiac Device-Related Infections and Endocarditis: A JACC: Cardiovascular Imaging Expert Panel Statement

The diagnosis of cardiac device infection and, more importantly, accurate localization of the infection site, such as defibrillator pocket, pacemaker lead, along the peripheral driveline or central portion of the left ventricular assist device, prosthetic valve ring abscesses, and perivalvular extensions, remain clinically challenging. Although transthoracic and transesophageal echocardiography are the first-line imaging tests in suspected endocarditis and for assessing hemodynamic complications, recent studies suggest that cardiac computed tomography (CT) or CT angiography and functional imaging with ¹⁸F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) with CT (FDG PET/CT) may have an incremental role in technically limited or inconclusive cases on echocardiography. One of the key benefits of FDG PET/CT is in its detection of inflammatory cells early in the infection process, before morphological damages ensue. However, there are many unanswered questions in the literature. In this document, we provide consensus on best practices among the various imaging studies, which includes the detection of cardiac device infection, differentiation of infection from inflammation, image-guided patient management, and detailed recommendations on patient preparation, image acquisition, processing, interpretation, and standardized reporting.

Tissues attached to retrieved leadless pacemakers: Histopathological evaluation of tissue composition in relation to implantation time and complications

BACKGROUND

Leadless pacemakers (LPs) have proven safe and effective, but device revisions remain necessary. Either replacing the LP or implanting a new adjacent LP is feasible. Replacement seems more appealing, but encapsulation and tissue adhesions may hamper the safety and efficacy of LP retrieval.

OBJECTIVE

We determined the incidence and cellular characteristics of tissue adherent to retrieved LPs and the potential implications for end-of-life strategy.

METHODS

All 15 consecutive successful Nanostim LP retrievals in a tertiary center were included. We assessed the histopathology of adherent tissue and obtained clinical characteristics.

RESULTS

Adherent tissue was present in 14 of 15 retrievals (93%; median implantation duration 36 months; range 0-96 months). The tissue consisted of fibrosis (n = 2), fibrosis and thrombus (n = 9), or thrombus only (n = 3). In short-term retrievals (<1 year), mostly fresh thrombi without fibrosis were seen. In later retrievals, the tissue consisted of fibrosis often with organizing or lytic thrombi. Fibrosis showed different stages of organization, notably early fibrocellular and later fibrosclerotic tissue. Inflammatory cells were seen (n = 4) without signs of infection. Tricuspid valve material was retrieved in 1 patient after 36 months, resulting in increased tricuspid regurgitation.

CONCLUSION

Our results suggest that fibrosis and thrombus adherent to LPs are common and encapsulate the LP as seen in transvenous pacemakers. LPs may adhere to the tricuspid valve or subvalvular apparatus affecting retrieval safety. The end-of-life strategy should be optimized by incorporating risk stratification for excessive fibrotic encapsulation and adhesions.

The prognostic value of transesophageal echocardiography after transvenous lead extraction: landscape after battle

Background

In patients undergoing transvenous lead extraction (TLE) transesophageal echocardiography (TEE) provide valuable information after procedure.

Methods

We analyzed data from 936 TEE performed in patients undergoing TLE between 2015 and 2019 (mean follow-up 566.23±224.47 days) and assessed the role of echocardiographic phenomena after procedure.

Results

Increment in tricuspid regurgitation (TR) was observed in 9% of patients after TLE. Factors increasing the risk of TR were: binding sites between lead and right ventricle (RV) (OR: 5.429), tricuspid valve (TV) (OR: 3.42), superior vena cava (SVC) (OR: 3.30) and lead-to-lead adhesions (OR: 2.88). Predisposing factors of residual structures after TLE were: asymptomatic masses on the leads (AMEL) (OR: 1.68), binding sites between SVC and cardiac structures (OR: 1.72), and multiple leads (OR: 1.30). Probability of vegetation remnants increased in the presence of abandoned leads (OR: 7.91). The risk factors of tamponade were: dwell time of the oldest lead (OR: 1.17), lead-to-lead adhesion (OR: 22.47), binding sites between lead and TV (OR: 6.08), RA (OR: 11.50), SVC (OR: 4.47), higher LVEF (OR: 2.35; P=0.006), female gender (OR: 5.43), multiple leads (OR: 2.11), looped leads (OR: 4.90) and AMEL (OR: 6.42). The risk of lead fracture was increased by: lead-to-lead adhesion (OR: 5.69), fibrosis binding the lead to RV (OR: 5.16), RA (OR: 2.39) and dwell time of the oldest lead (OR: 1.068). The mortality rate was 11.97% during follow-up. The risk of death was increased by: severe TR and vegetation remnants.

Conclusions

The most important phenomena evaluated after TLE are: tricuspid valve function, residual fibrosis and vegetation remnants, progression of pericardial effusion and retained lead fragments. Postoperative TEE provides information about the results of TLE and helps establish further management.

A Novel Clinical Perspective on New Masses after Lead Extraction (Ghosts) by Means of Intracardiac Echocardiography

Background: A lead-reactive fibrous capsule (FC) identified by ultrasounds as an atrial or ventricular lead thickness of more than 1 mm above the vendor-declared lead diameter (TL) and its local fibrotic attachment to the cardiac wall (FAC) have never been investigated in vivo, so their relationship with post-extraction masses (ghost) is not known. Methods: Intracardiac echocardiography (ICE) was performed twice during the same extraction procedure in 40 consecutive patients: before and immediately after infected lead extraction Results: The ghost detection rate was high: 60% (24/40 patients); ICE could identify both TL and FAC, TL being noted in 25/40 (62%) patients and FAC in 12/40 patients (30%). Both TL and FAC were significantly associated with ghosts (p < 0.001 and p = 0.002, respectively), but TL had a higher prediction power. The specificity was similar: 94% (15/16) and 100% (16/16), respectively, but TL showed a much higher sensitivity: 100%, (24/24) vs 50% (12/24) (p = 0.016). The ghost group did not show a higher event rate in the follow-up (mean follow-up time = 20 ± 17 months). Conclusion: ICE is able to evaluate both TL and FAC in vivo; ghosts are mostly benign remnants of fibrotic lead capsule cut off during extraction and retained inside the heart by FAC.

A Ghost Left Behind After Transvenous Lead Extraction: A Finding to be Feared

Patient: Male, 72-year-old

Final Diagnosis: Infective endocarditis

Symptoms: Falls • weakness

Medication: —

Clinical Procedure: Removal of pacemaker

Specialty: Cardiology

Histological properties of oscillating intracardiac masses associated with cardiac implantable electric devices

Background

There have been a few cases of echogenic cardiac implantable electric device (CIED) lead‐associated oscillating intracardiac masses (ICMs) in leads imaged by echocardiography. The histological properties of ICMs could help clarify the etiological diagnosis. Although there is extensive literature on mass size, the histological properties of such masses have not been characterized. The aim of this research was to clarify the histological features of oscillating ICMs in CIED patients.

Methods

Preoperative echocardiography was performed in all candidates for CIED removal. In the patients with ICMs, specimens were obtained by 3 methods: direct tissue collection during open‐heart surgery; tissue collection together with the CIED lead during transvenous extraction; and tissue collection by catheter vacuum during transvenous CIED removal. A standard histopathological examination of ICM tissue was performed.

Results

A total of 106 patients underwent lead removal in our institute (April 2009‐March 2018); 14 patients had an ICM (13.2%), and 7 specimens were obtained in patients with CIED lead‐related ICM. Following histological examination, 2 types of ICM were identified: one mainly composed of thickened endocardium (EN type; 3 patients), and the other mainly an aggregate of inflammatory cells as a neutrophil cell (NC type; 4 patients).

Conclusions

Two histological types of intracardiac masses, including a thickened endocardium type and a neutrophil cell type, were identified. These classifications might help make an accurate histological diagnosis of lead‐associated intracardiac masses.

Pseudoleads on Transesophageal Echocardiography

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Management of an infected ICD.

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Definition of pseudoleads.

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Pseudoleads as seen on TEE following complete removal of an infected cardiac device.

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Management options for bacteremic patients with pseudoleads.

Nursing Management for Patients Postoperative Cardiac Implantable Electronic Device Placement

As cardiac implantable electronic devices (CIEDs) continue to evolve and patients continue to live longer, the use of these devices increases. CIEDs include permanent pacemakers, implanted cardioverter-defibrillators, and cardiac resynchronization therapy devices. Over the last 2 decades, the functionality of these devices has increased and can be complex. Critical care nurses should be equipped with the knowledge to care for patients immediately postoperative CIED placement and for patients admitted to critical care units with CIEDs already in place. Patients with CIEDs are a vulnerable population with special needs and considerations for management.

Unusual presence of 'ghosts' following lead extraction for recurrent reactive pericarditis: a case report

Background

The presence of a persistent fibrous sheath in right-sided heart chambers after transvenous lead extraction has already been described in some studies as echocardiographic tubular mobile masses called ‘ghosts’. Their presence has been associated with cardiac device-related infective endocarditis or local device infection, but to the best of our knowledge, this is the first case where ‘ghosts’ have been reported among non-infected patients.

Case summary

We present a case of a 73-year-old woman hospitalized due to worsening dyspnoea and a significant pericardial effusion, relapsed after pericardiocentesis with removal of about 1500 mL of non-haemorrhagic fluid. The patient’s history revealed a previous dual-chamber pacemaker implantation due to symptomatic sick sinus syndrome. Transoesophageal echocardiography (TOE), essential to exclude endocarditis vegetations suggested an etiopathogenesis of mechanical irritation caused by the distal end of the passive fixation atrial lead on the right atrial appendage wall. Considering the echocardiographic report and the condition of reactive pericarditis with the early relapse of the significant pericardial effusion after pericardiocentesis, we opted for a lead removal procedure to eliminate the stimulus causing the irritation, with transoesophageal echocardiographic monitoring, thus the early detection of a ‘ghost’ was possible.

Discussion

This is the first clinical case describing the presence of fibrin ‘ghosts’ sometime after the implantation of a pacemaker, highlighting a non-exclusively infectious genesis, and emphasizing the importance of TOE for the early detection of this post-extraction complication and its monitoring.

Transvenous Lead Extraction: A Clinical Commentary for Anesthesiologists

With increasing use of cardiovascular implantable electronic devices, the need for lead extractions has increased to an annual volume of more than 10,000 extractions worldwide. This article provides a focused clinical commentary on the perioperative management, identification, and treatment of life-threatening complications associated with lead extractions. In addition, a summary of indications, techniques, and lead extraction complications is provided. Although uncommon, lead extractions are associated with a consistent rate of major procedure-related complications and mortality. Major life-threatening complications include vascular laceration, cardiac avulsion, hemothorax, pericardial effusion, and cardiac arrest. Comprehensive preoperative risk assessment and adequate planning and preparedness are crucial to decreasing all procedure-related adverse events. The location of the procedure (electrophysiology suite v hybrid operating room) and the nature of cardiac surgical backup are determined after meticulous risk stratification. In addition to decisions on vascular access, invasive monitoring, and modality of rhythm support, transesophageal echocardiography plays a crucial role in early diagnosis, timely management, and potential prevention of these complications.

The details of an unusual "ghost" after transvenous lead extraction: Three-dimensional computed tomography analysis

Transvenous lead extraction (TLE) is performed to prevent deaths in patients with device infections. Intracardiac masses detected by echocardiography, i.e., “ghosts,” are reported in 8% of patients after a TLE in retrospective studies and in 14% in prospective studies. We herein describe a case with unusual ghosts after a TLE. Three-dimensional computed tomography (3DCT) is useful for revealing all the details of unusual ghosts. In this case, the residual silicone insulation and “cast,” including the fibrous sheath and severe calcifications could be visualized and differentiated by 3DCT.

Presence of 'ghosts' and mortality after transvenous lead extraction

Aims

The number of cardiovascular implantable electronic devices has increased progressively, leading to an increased need for transvenous lead extraction (TLE) due to device infections. Previous studies described 'ghost' as a post-removal, new, tubular, mobile mass detected by echocardiography following the lead's intracardiac route in the right-sided heart chambers, associated with diagnosis of cardiac device-related infective endocarditis. We aimed to analyse the association between 'ghosts' assessed by transesophageal echocardiography (TEE) and intracardiac echocardiography (ICE) and mortality in patients undergoing TLE.

Methods and results

We prospectively enrolled 217 patients (70 ± 13 years; 164 males) undergoing TLE for systemic infection (139), local device infection (67), and lead malfunction (11). All patients underwent TEE before and 48 h after TLE and ICE during TLE. Patients were allocated to two groups: either with (Group 1) or without (Group 2) post-procedural 'ghost'. Mid-term clinical follow-up was obtained in all patients (11 months, IQR 1-34 months). We identified 30 (14%) patients with 'ghost', after TLE. The significant predictors of 'ghost' were Charlson co-morbidity index (HR = 1.24, 95% CI 1.04-1.48, P = 0.03) and diagnosis of endocarditis assessed by ICE (HR = 1.82, 95% CI 1.01-3.29, P = 0.04). Mortality was higher in Group 1 than in Group 2 (28 vs. 5%; log-rank P < 0.001). Independent predictors of mid-term mortality were the presence of 'ghost' and systemic infection as the clinical presentation of device infection (HR = 3.47, 95% CI 1.18-10.18, P = 0.002; HR = 3.39, 95% CI 1.15-9.95, P = 0.001, respectively).

Conclusion

The presence of 'ghost' could be an independent predictor of mortality after TLE, thus identifying a subgroup of patients who need closer clinical surveillance to promptly detect any complications.

Diagnostic value of imaging in infective endocarditis: a systematic review

Sensitivity and specificity of the modified Duke criteria for native valve endocarditis are both suboptimal, at approximately 80%. Diagnostic accuracy for intracardiac prosthetic material-related infection is even lower. Non-invasive imaging modalities could potentially improve diagnosis of infective endocarditis; however, their diagnostic value is unclear. We did a systematic literature review to critically appraise the evidence for the diagnostic performance of these imaging modalities, according to PRISMA and GRADE criteria. We searched PubMed, Embase, and Cochrane databases. 31 studies were included that presented original data on the performance of electrocardiogram (ECG)-gated multidetector CT angiography (MDCTA), ECG-gated MRI, ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) PET/CT, and leucocyte scintigraphy in diagnosis of native valve endocarditis, intracardiac prosthetic material-related infection, and extracardiac foci in adults. We consistently found positive albeit weak evidence for the diagnostic benefit of ¹⁸F-FDG PET/CT and MDCTA. We conclude that additional imaging techniques should be considered if infective endocarditis is suspected. We propose an evidence-based diagnostic work-up for infective endocarditis including these non-invasive techniques.

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.

Outcomes of Transvenous Lead Extraction for Cardiovascular Implantable Electronic Device Infections in Patients With Prosthetic Heart Valves

Background—

Lead-related or valve-related endocarditis can complicate cardiovascular implantable electronic device (CIED) infection in patients with both CIED and prosthetic valves. The objective of this study was to determine the outcomes of transvenous lead extraction for CIED infection in patients with prosthetic valves.

Methods and Results—

We retrospectively screened 794 transvenous lead extraction procedures, between September 1, 2001 and August 31, 2012, at Mayo Clinic to identify patients with prosthetic valves who underwent lead extraction for infection. Demographic, clinical, and follow-up characteristics were analyzed. In total, 51 patients (6%) met the study inclusion criteria, of whom 20 had pocket infection and 31 had lead-related or valve-related, or both, endocarditis or bloodstream infection (mean age, 67 [18] years). Staphylococcal species were the most common pathogens, including Staphylococcus aureus in 20 cases (39%) and coagulase-negative staphylococci in 19 cases (37%). Overall, 127 transvenous leads (median lead age, 52 months) were extracted. Of these leads, 123 (97%) were removed completely. The in-hospital mortality rate was 9.8%; no deaths were attributable to the extraction procedure. Ninety-five percent of patients who survived had no evidence of recurrent device-related or valve-related infection.

Conclusions—

Transvenous lead extraction seems safe and curative in patients with CIED infection and prosthetic valves. Cure of infection can be achieved in the majority of patients with complete CIED removal and antimicrobial therapy and without valve surgery.

The diagnostic ability of echocardiography for infective endocarditis and its associated complications

Echocardiography, transthoracic and transoesophageal, plays a key role in the diagnosis and prognosis assessment of patients with infective endocarditis. It constitutes a major Duke criterion and is pivotal in treatment guiding. Seven echocardiographic findings are major criteria in the diagnosis of infective endocarditis (IE) (vegetation, abscess, pseudoaneurysm, fistulae, new dehiscence of a prosthetic valve, perforation and valve aneurysm). Echocardiography must be performed as soon as endocarditis is suspected. Transoesophageal echocardiography should be done in most cases of left-sided endocarditis to better define the anatomic lesions and to rule out local complications. Transoesophageal echocardiography is not necessary in isolated right-sided native valve IE with good quality transthoracic examination and unequivocal echocardiographic findings. Echocardiography is a very useful tool to assess the prognosis of patients with IE at any time during the course of the disease. Echocardiographic predictors of poor outcome include presence of periannular complications, prosthetic dysfunction, low left ventricular ejection fraction, pulmonary hypertension and very large vegetations.

Management of Cardiac Implantable Electronic Device Infection

Despite improved preventive measures, infection associated with the use of cardiac implantable electronic devices (CIEDs) to treat often life-threatening conditions is rising at an average annual rate of almost 5 %. This rise is being driven by the increasing complexity of CIED technology and by the advancing age and co-morbidities of the patients. Although CIED infection is usually suspected based on local signs at the generator pocket site, diagnosis can be challenging in patients presenting no local manifestations or symptoms. Diagnostic methods include microbiological testing and echocardiography, and may be completed by positron emission tomography (PET)/computed tomography (CT) scan in selected cases. CIED infection requires a multidisciplinary approach in view of hardware extraction, targeted antibiotic therapy and reimplantation on an as-needed basis. Antibiotic prophylaxis targeting staphylococcal flora is recommended but the relation of these infections to medical care exposes patients to multi-resistant bacteria. New preventive measures utilising an antibacterial sleeve look promising. Treatment can be started on an empirical basis using an antistaphylococcal agent but must be continued using targeted antibiotic therapy. Crucial questions remain as to the best prevention strategy, optimal duration and timing of antibiotic therapy, and the most effective reimplantation technique.

Guidelines for the diagnosis, prevention and management of implantable cardiac electronic device infection. Report of a joint Working Party project on behalf of the British Society for Antimicrobial Chemotherapy (BSAC, host organization), British Heart Rhythm Society (BHRS), British Cardiovascular Society (BCS), British Heart Valve Society (BHVS) and British Society for Echocardiography (BSE)

Infections related to implantable cardiac electronic devices (ICEDs), including pacemakers, implantable cardiac defibrillators and cardiac resynchronization therapy devices, are increasing in incidence in the USA and are likely to increase in the UK, because more devices are being implanted. These devices have both intravascular and extravascular components and infection can involve the generator, device leads and native cardiac structures or various combinations. ICED infections can be life-threatening, particularly when associated with endocardial infection, and all-cause mortality of up to 35% has been reported. Like infective endocarditis, ICED infections can be difficult to diagnose and manage. This guideline aims to (i) improve the quality of care provided to patients with ICEDs, (ii) provide an educational resource for all relevant healthcare professionals, (iii) encourage a multidisciplinary approach to ICED infection management, (iv) promote a standardized approach to the diagnosis, management, surveillance and prevention of ICED infection through pragmatic evidence-rated recommendations, and (v) advise on future research projects/audit. The guideline is intended to assist in the clinical care of patients with suspected or confirmed ICED infection in the UK, to inform local infection prevention and treatment policies and guidelines and to be used in the development of educational and training material by the relevant professional societies. The questions covered by the guideline are presented at the beginning of each section.

Extraction of chronically implanted cardiovascular electronic device leads

OPINION STATEMENT

Cardiovascular implantable electronic devices (CIED) are a remarkable success story. These systems are widely used to prevent symptomatic bradycardia, treat malignant tachyarrhythmia, and to restore a more physiologic contraction to a failing left ventricle. Implantation of a CIED usually involves a lifelong commitment to this therapy, which, unfortunately, is not free from complication requiring removal and/or replacement of all or part of the system. The major obstacle to removal of a CIED is the fibrous attachments that develop between a lead and co-existent leads, veins, and the heart. This process increases over time such that, by one year, removal by traction alone may be problematic and, if aggressive, result in complication. Physicians, surgeons, and engineers have refined techniques of percutaneous lead extraction and developed tools, which have facilitated the process, increased success, and lowered the incidence of complication. Extraction may be performed for a variety of indications some of which are unanimously agreed upon while others remain controversial. Proponents of a broadened application of extraction have proffered the concept of 'lead management,' which includes the removal of all leads that are not clinically relevant to the patient. The benefit of this approach would be to limit the risk of future complication, such as venous occlusion or thromboembolism, and to obviate the increase in difficulty of extraction (due to longer implant duration) that might accompany removal should that be required in the future. Intuitively appealing as this approach might be, there is little evidence supporting it, and the extraordinarily large number of patients currently implanted with recalled ICD leads is indicative of the potential impact this practice may have. This review will discuss extraction, its indications, and outcomes.

Cardiac imaging in infectious endocarditis

Infectious endocarditis remains both a diagnostic and a treatment challenge. A positive outcome depends on a rapid diagnosis, accurate risk stratification, and a thorough follow-up. Imaging plays a key role in each of these steps and echocardiography remains the cornerstone of the methods in use. The technique of both transthoracic echocardiography and transoesophageal echocardiography has been markedly improved across the last decades and most recently three-dimensional real-time echocardiography has been introduced in the management of endocarditis patients. Echocardiography depicts structural changes and abnormalities in the heart, but it does not uncover the underlying pathophysiological processes at the cellular or molecular level. This problem is addressed with introduction of new molecular imaging methods as (18)F-fluorodesoxyglucose ((18)F-FDG) PET-CT and single photon emission computed tomography fused with conventional CT (SPECT/CT). Of these methods, (18)F-FDG PET-CT carries the best promise for a future role in endocarditis. But there are distinct limitations with both SPECT/CT and (18)F-FDG PET-CT which should not be neglected. MRI and spiral CT are methods primarily used in the search for extra cardial infectious foci. A flowchart for the use of imaging in both left-sided and right-sided endocarditis is suggested.

Diagnostic yield of FDG positron-emission tomography/computed tomography in patients with CEID infection: a pilot study

AIMS

Whole body imaging with (18)F-fluorodeoxyglucose positron-emission tomography/computed tomography (FDG PET/CT) has proven useful in various infectious diseases. The purpose of this pilot study was to assess the diagnostic yield of FDG PET/CT in patients with cardiac implantable electronic device (CIED) infection.

METHODS AND RESULTS

A total of 21 patients with CIED infection were prospectively included. Diagnosis of CIED infection was made in accordance with current criteria. It was classified in three categories, i.e. superficial skin infection, pocket site infection, or cardiac device-related infective endocarditis (CDRIE). All patients underwent FDG PET/CT. Scans were interpreted blindly, i.e. without prior knowledge of diagnosis, by experienced nuclear medicine physicians. The accuracy of FDG PET/CT was assessed for each diagnostic category. Findings demonstrated superficial skin infection in 1 patient, pocket site infection in 15, and CDRIE in 13 (definite: 7; possible: 6). In patients with pocket site infection, the sensitivity and specificity of FDG PET/CT were 86.7% [59.5-98.3, 95% confidence interval (CI)] and 100% [42.1-100, 95% CI]. The only patient with superficial skin infection was accurately identified by FDG PET/CT. The sensitivity and specificity of FDG PET/CT in patients with CDRIE were 30.8% [9.1-61.4, 95% CI] and 62.5% [24.5-91.5, 95% CI]. Most false-negative results occurred in patients who had undergone previous antimicrobial treatment.

CONCLUSION

This study indicates that FDG PET/CT is highly accurate for the diagnosis of skin and pocket CIED infection but low for infective endocarditis. This suggests that the reliability of FDG PET/CT findings in management decision making varies according to the type of CIED infection.

Role of transthoracic and transesophageal echocardiography in right-sided endocarditis: one echocardiographic modality does not fit all

The added value of transesophageal echocardiography (TEE) over transthoracic echocardiography in the assessment of left-sided infective endocarditis has been extensively validated in the literature. Little research has dealt with the role of echocardiography in right-sided infective endocarditis (RSE), however. In this review, the differences between RSE and left-sided endocarditis and the different types of RSE according to the types of patients who have the disease are described. Both issues have important implications for echocardiographic workup. Moreover, a systematic echocardiographic protocol to avoid missing right-sided vegetations and several specific morphologic aspects of RSE are reviewed. Normal right-sided structures, which may mimic vegetations, particularly when the clinical picture is compatible, are described. Finally, the value of transthoracic echocardiography and TEE in RSE is reviewed according to the publications available. The diagnostic yield of transthoracic echocardiography is comparable with that of TEE in intravenous drug users. On the contrary, TEE is mandatory in patients with cardiac devices. A Bayesian-based diagnostic approach is proposed for a third poorly characterized group of patients with RSE who are not drug addicts, have no cardiac devices, and have no left-sided endocarditis (the "three no's" endocarditis group).

Device-related infective endocarditis, with special consideration of implanted intravascular and cardiac devices in a predominantly male population

BACKGROUND

The relationship between invasive medical devices and infective endocarditis (IE) has not been comprehensively assessed. We describe our experience of patients with IE, with particular attention to the role of pre-existing intravascular catheters and implanted cardiac devices in the pathogenesis.

METHODS

We performed a retrospective review of hospital records over a 10-y period (1997-2007), and included patients with 'definite' or 'possible' IE as per the modified Duke criteria. The complete electronic medical record was reviewed for the presence of intravascular devices prior to the onset of IE, including intravascular catheters and implanted cardiac devices (defibrillators and pacemakers).

RESULTS

We identified 155 patients with IE. Infection involved a native valve in 124 (80%) patients and a prosthetic valve in 15 (9.7%). In the remaining 16 (10.3%) patients, infection was attributed to an implanted cardiac device. The most commonly identified source of infection was a central venous catheter, accounting for 17.4% of patients, followed by an implanted cardiac device in 10.3% of patients. Staphylococcus aureus was the most commonly isolated organism in catheter-associated IE and cardiac device-associated IE (31.9% and 62.5%, respectively). Thirty-five (22.5%) patients died within 90 days. Mortality was 31.9% in patients with IE caused by methicillin-resistant S. aureus (MRSA).

CONCLUSIONS

Intravascular catheters and cardiac implantable devices are common sources of infection leading to IE, and the intracardiac devices themselves often become infected, with MRSA as the predominant pathogen.