Infective endocarditis in patients with an implanted transcatheter aortic valve: Clinical characteristics and outcome of a new entity

Endocarditis in critically ill patients: a review

PURPOSE OF REVIEW

To summarize the advances in literature that support the best current practices regarding infective endocarditis (IE) in critically ill patients.

RECENT FINDINGS

IE due to rheumatic diseases has decreased significantly, and in fact, the majority of cases are associated with degenerative valvopathies, prosthetic valves, and cardiovascular implantable electronic devices. The Duke criteria were recently updated, addressing the increasing incidence of new risk factors for IE, such as IE associated with the use of endovascular cardiac implantable electronic devices and transcatheter implant valves. The presence of organ dysfunction, renal replacement therapies, or extracorporeal membrane oxygenation should be considered in the choice of drug and dosage in critically ill patients with suspected or confirmed IE. As highlighted for other severe infections, monitoring of therapeutic antibiotic levels is a promising technique to improve outcomes in critically ill patients with organ dysfunction.

SUMMARY

The diagnostic investigation of IE must consider the current epidemiological criteria and the diagnostic particularities that these circumstances require. A careful evaluation of these issues is necessary for the prompt clinical or surgical management of this infection.

Surgery for Infective Endocarditis after Primary Transcatheter Aortic-Valve Replacement-A Retrospective Single-Center Analysis

Transcatheter aortic-valve replacement (TAVR) is increasingly being used for the treatment of aortic-valve stenosis. Therefore, the total number of patients with an aortic-valve prosthesis is increasing, causing the incidence of prosthetic-valve endocarditis to increase.

METHODS

Between March 2016 and July 2019, ten patients underwent surgery due to prosthetic-valve endocarditis after TAVR. They were identified in our institutional database and analyzed.

RESULTS

Infective endocarditis was diagnosed 17 ± 16 month after TAVR. Mean age was 79 ± 4.4 years. Microbiological detection showed 6/10 positive blood cultures for enterococcus faecalis. Median EuroScore II was 24.64%. The mean size of the surgically replaced aortic prosthesis was 23.6 ± 1.3 and that of the TAVR was 28.4 ± 2.3 mm. The surgically implanted aortic valves had a mean gradient of 8.5 ± 2.2 mmHg. One patient died in hospital due to septic multiorgan failure. After discharge, all patients survived with a mean follow-up of 9 ± 8 month.

CONCLUSIONS

With a rising number of patients after TAVR, prosthetic-valve endocarditis will increasingly occur in patients who were previously considered high or intermediate risk. Our results show that patients with TAVR infective endocarditis can be operated on with good results. Surgical therapy should not be withheld from TAVR patients with infective endocarditis.

Case report: Fatal systemic embolism caused by early prosthetic valve endocarditis after Bentall surgery

Prosthetic valve endocarditis (PVE) is a rare but dangerous complication of Bentall surgery and Staphylococcus epidermidis PVE involving multiple valves simultaneously during the early postoperative period has not been reported. A 42 year old patient admitted to intensive care unit with fever 1 month after aortic valve replacement (Bentall procedure). Echocardiography was of great diagnosis value and suggested large, mobile vegetations on both the prosthetic aortic valve and native tricuspid valve. The presence of Staphylococcus epidermidis was revealed by multiple blood cultures. Surgery was not performed because of the history of aortic valve replacement 1 month ago. He developed acute right femoral artery thromboembolism, multiple cerebral infarction and splenic infarction during hospitalization and died of cerebral infarction after being discharged. This case underlines that patients with early PVE may have poor prognosis and fatal systemic embolism should be aware of in PVE patients with large vegetations present with dyskinesia, abdominal pain, and limb numbness. The timely echocardiography and vascular ultrasound are primary and reliable diagnostic methods in this scenario.

Infective Endocarditis in the Elderly: Challenges and Strategies

The specific management of infective endocarditis (IE) in elderly patients is not specifically addressed in recent guidelines despite its increasing incidence and high mortality in this population. The term "elderly" corresponds to different ages in the literature, but it is defined by considerable comorbidity and heterogeneity. Cancer incidence, specifically colorectal cancer, is increased in older patients with IE and impacts its outcome. Diagnosis of IE in elderly patients is challenging due to the atypical presentation of the disease and the lower performance of imaging studies. Enterococcal etiology is more frequent than in younger patients. Antibiotic treatment should prioritize diminishing adverse effects and drug interactions while maintaining the best efficacy, as surgical treatment is less commonly performed in this population due to the high surgical risk. The global assessment of elderly patients with IE, with particular attention to frailty and geriatric profiles, should be performed by multidisciplinary teams to improve disease management in this population.

Infective Endocarditis: New Challenges in a Classic Disease

Infective endocarditis is a relatively rare, but deadly infection, with an overall mortality of around 20% in most series. Clinical manifestations have evolved in response to significant epidemiological shifts in industrialized nations, with a move toward a nosocomial or health-care-related pattern, in older patients, with more episodes associated with prostheses and/or intravascular electronic devices and a predominance of staphylococcal and enterococcal etiology.Diagnosis is often challenging and is based on the conjunction of clinical, microbiological, and imaging information, with notable progress in recent years in the accuracy of echocardiographic data, coupled with the recent emergence of other useful imaging techniques such as cardiac computed tomography (CT) and nuclear medicine tools, particularly ¹⁸F-fluorodeoxyglucose positron emission/CT.The choice of an appropriate treatment for each specific case is complex, both in terms of the selection of the appropriate agent and doses and durations of therapy as well as the possibility of using combined bactericidal antibiotic regimens in the initial phase and finalizing treatment at home in patients with good evolution with outpatient oral or parenteral antimicrobial therapies programs. A relevant proportion of patients will also require valve surgery during the active phase of treatment, the timing of which is extremely difficult to define. For all the above, the management of infective endocarditis requires a close collaboration of multidisciplinary endocarditis teams.

Ampicillin Plus Ceftriaxone Regimen against Enterococcus faecalis Endocarditis: A Literature Review

Enterococcus faecalis infective endocarditis (EFIE) continues to represent a potentially fatal infectious disease characterized by elevated morbidity and mortality. Despite advances in antimicrobial therapy, changing demographics and the reduced availability of useful antibiotics combined with the dissemination of multi-drug resistant strains, the mortality rate remained unchanged in the last decades. Nowadays, optimizing the antibiotic regimen is still of paramount importance. Historically, aminoglycosides were considered as a cornerstone for treatment even though their use is associated with a high risk of kidney failure. It is against this background that, in recent years, several studies have been carried in order to assess the validity of alternative therapeutic approaches, including combinations of beta-lactams, that, acting synergistically, have yielded useful results in different clinical settings. In this scenario, we searched and critically report clinical studies assessing the efficacy and safety of double beta-lactam therapy in treating EFIE.

Current Challenges in the Management of Infective Endocarditis

Infective endocarditis is a relatively rare, but deadly cause of sepsis, with an overall mortality ranging from 20 to 25% in most series. Although the classic clinical classification into syndromes of acute or subacute endocarditis have not completely lost their usefulness, current clinical forms have changed according to the profound epidemiological changes observed in developed countries. In this review, we aim to address the changing epidemiology of endocarditis, several recent advances in the understanding of the pathophysiology of endocarditis and endocarditis-triggered sepsis, new useful diagnostic tools as well as current concepts in the medical and surgical management of this disease. Given its complexity, the management of infective endocarditis requires the close collaboration of multidisciplinary endocarditis teams that must decide on the diagnostic approach; the appropriate initial treatment in the critical phase; the detection of patients needing surgery and the timing of this intervention; and finally the accurate selection of patients for out-of-hospital treatment, either at home hospitalization or with oral antibiotic treatment.

A review of recommendations for infective endocarditis prevention in patients undergoing transcatheter aortic valve implantation

Infective endocarditis (IE) after transcatheter aortic valve implantation (TAVI) is a new disease entity. The rate of IE after TAVI is similar to that after surgical aortic valve replacement (SAVR), but mortality and prevalence of Enterococcus spp. as causing pathogens are significantly higher. Guidelines on infection prevention measures before TAVI procedures are currently lacking. We performed a structured review of the available data to provide interim recommendations based on guidelines to prevent infections issued by the World Health Organization as well as guidelines by professional societies from Europe and the USA. Such interim recommendations based on expert opinions are probably justified until large randomised trials provide strong evidence for infection control in TAVI, because IE after TAVI is often related to the TAVI procedure itself and the associated mortality rate is high. Antibiotic prophylaxis should be adapted from an intravenous cephalosporin to, e.g., amoxicillin/clavulanic acid, to cover enterococci. In addition, infection control should follow operating room standards as far as is reasonable, even if the evidence for this recommendation is very low. These recommendations are endorsed by the International Society for Cardiovascular Infectious Diseases (ISCVID).

Surgical treatment of transcatheter aortic valve infective endocarditis

There is growing interest in infections occurring after transcatheter aortic valve implantation (TAVI). The incidence, and clinical and anatomical features suggest many similarities with prosthetic valve endocarditis. The survival of patients with an infected TAVI prosthesis is generally poor; however, only a minority of them (10%) have undergone treatment with surgical explantation of the infected prosthesis. A literature search was performed using online databases. Papers reporting surgical treatment of TAVI prosthesis infections were retrieved, focusing on pre- and intraoperative characteristics and early outcome. Thirty-seven papers ultimately provided information on 107 patients. Their mean ± standard deviation (SD) age was 76 ± 8 years and 72% were male. The mean ± SD time interval between the TAVI procedure and reoperation was 10 ± 10 months. Annular abscess formation was described in 34% of cases and mitral valve involvement in 31%. All patients underwent TAVI prosthesis explantation and surgical aortic valve replacement; concomitant mitral valve replacement was necessary in 22% of cases. Postoperative in-hospital mortality was 28%. Surgical explantation of infected TAVI prostheses was associated with a high postoperative mortality, although these initial experiences included elderly and high-risk patients. Considering the expansion of TAVI procedures towards younger and lower-risk patients, surgical treatment of TAVI endocarditis may represent the best option for a life-saving procedure.

Endocarditis in Patients with Aortic Valve Prosthesis: Comparison between Surgical and Transcatheter Prosthesis

The interventional treatment of aortic stenosis is currently based on transcatheter aortic valve implantation/replacement (TAVI/TAVR) and surgical aortic valve replacement (SAVR). Prosthetic valve infective endocarditis (PVE) is the most worrisome complication after valve replacement, as it still carries high mortality and morbidity rate. Studies have not highlighted the differences in the occurrence of PVE in SAVR as opposed to TAVR, but the reported incidence rates are widely uneven. Literature portrays different microbiological profiles for SAVR and TAVR PVE: Staphylococcus, Enterococcus, and Streptococcus are the pathogens that are more frequently involved with differences regarding the timing from the date of the intervention. Imaging by means of transoesophageal echocardiography, and computed tomography (CT) Scan is essential in identifying vegetations, prosthesis dysfunction, dehiscence, periannular abscess, or aorto-ventricular discontinuity. In most cases, conservative medical treatment is not able to prevent fatal events and surgery represents the only viable option. The primary objectives of surgical treatment are radical debridement and the removal of infected tissues, the reconstruction of cardiac and aortic morphology, and the restoration of the aortic valve function. Different surgical options are discussed. Fast diagnosis, the adequacy of antibiotics treatment, and prompt interventions are essential in preventing the negative consequences of infective endocarditis (IE).

[Infection and TAVI]

Since trans-catheter valve implantation (TAVI) has emerged for severe symptomatic aortic stenosis treatment, infective endocarditis (IE) appears as a rare but severe complication. Like surgical aortic valve remplacement infective endocarditis (SAVR-IE), TAVI-IE has a noxious impact on morbidity and mortality. Compared to SAVR-IE, TAVI-IE present some similarities as well as differences. Most TAVI-IE occurred during the first year and enterococcus is the more common pathogen. A multimodality imaging approach including echocardiography, multislice computed tomography (CT) and positron emission tomography-CT with blood culture is necessary for the diagnosis. In this high-risk population, the vast majority of TAVI-IE patients are treated with antibiotic therapy alone. Consequently to the expanded indication, the increasing number of TAVI-IE will appear more frequently. If initially only few clinical cases of IE were reported, sparse observational multicenter registries have now been published. Relevant differences were noted on these registries, but some recent publications have provided new informations on IE. The present review reports incidence, symptoms, microbiological profil, risk factors and clinicals outcomes of TAVI-IE. Eventually, we describe the management and the treatment of IE in the context of TAVI.

Different types of endocarditis after transcatheter aortic valve implantation

INTRODUCTION

Infective endocarditis (IE) may take different faces in patients after transcatheter aortic valve implantation (TAVI).

OBJECTIVES

The primary aim of this study was to describe echocardiographic and clinical characteristics of TAVI's patients suffered from IE.

METHODS

In a single-center, retrospective study we analyzed 311 consecutive patients treated with TAVI for severe aortic stenosis between 2010 and 2018.

RESULTS

According to modified Duke criteria, we confirmed IE in 2.2% of the cohort, however PVE of TAVI's valve in 1.2% only; rest of the group suffered from CDRiE and IE of the mitral valve. In PVE's group vegetations were localized inside the frame with or without bioprosthesis moderate stenosis or regurgitation. Only 1 pts developed significant TAVI's bioprosthesis' paravalvular leak. We observed no native aortic anulus involvement. Mortality rate in the PVE-TAVI's group was 75% regardless of the type of treatment.

CONCLUSIONS

The above findings show that IE following TAVI is a serious complication and various scenarios (also CDRiE and native valve IE) should be considered.

Prosthetic valve endocarditis: A challenging complication of prosthetic valves

Background

This study aims to evaluate the surgical outcomes of prosthetic valve endocarditis.

Methods

A total of 21 patients (6 males, 15 females; mean age 58.9±12.6 years; range, 33 to 79 years) who were surgically treated for prosthetic valve endocarditis between January 2013 and January 2018 were retrospectively analyzed. Surgical indications included persistent fever for more than seven days after antibiotherapy, congestive heart failure refractory to medical treatment, vegetations larger than 1 cm on echocardiography, the presence of fungal endocarditis, severe valvular leak and valvular dysfunction, and staphylococcal prosthetic valve endocarditis.

Results

Five patients had previous aortic valve replacement and three of the aortic prostheses were re-replaced. Two patients had coexisting native mitral valve endocarditis and double valve replacement was done. Thirteen patients had previous mitral valve replacement and 12 of the mitral prostheses were re-replaced. One patient had coexisting native aortic valve endocarditis and double valve re-replacement was done. Three patients had previous aortic valve replacement + mitral valve replacement. Mitral valve endocarditis was diagnosed in two patients and these patients had only mitral valve re-replacement. The other patient had double valve endocarditis, and double valve replacement was done. The mean time from the first operation to the development of endocarditis was 7.3±5.7 years. Of five lost patients, two died from multiple organ failure, one from low cardiac output, one from pneumonia, and one from respiratory failure.

Conclusion

Radical resection of the infected tissues is critical to achieve favorable surgical outcomes. Single valve replacement of the infected valve may be preferred in patients having previous double valve replacement. Mechanical valves or bioprostheses can be used for re-replacement procedures.

Methicillin-Resistant Staphylococcus aureus Prosthetic Valve Endocarditis: Pathophysiology, Epidemiology, Clinical Presentation, Diagnosis, and Management

Staphylococcus aureus prosthetic valve endocarditis (PVE) remains among the most morbid bacterial infections, with mortality estimates ranging from 40% to 80%. The proportion of PVE cases due to methicillin-resistant Staphylococcus aureus (MRSA) has grown in recent decades, to account for more than 15% of cases of S. aureus PVE and 6% of all cases of PVE. Because no large studies or clinical trials for PVE have been published, most guidelines on the diagnosis and management of MRSA PVE rely upon expert opinion and data from animal models or related conditions (e.g., coagulase-negative Staphylococcus infection). We performed a review of the literature on MRSA PVE to summarize data on pathogenic mechanisms and updates in epidemiology and therapeutic management and to inform diagnostic strategies and priority areas where additional clinical and laboratory data will be particularly useful to guide therapy. Major updates discussed in this review include novel diagnostics, indications for surgical management, the utility of aminoglycosides in medical therapy, and a review of newer antistaphylococcal agents used for the management of MRSA PVE.

The Changing Epidemiology of Infective Endocarditis in the Twenty-First Century

PURPOSE OF THE REVIEW

Infective endocarditis (IE) is a relatively infrequent infectious disease. It does, however, causes serious morbidity, and its mortality rate has remained unchanged at approximately 25%. Changes in IE risk factors have deeply impacted its epidemiology during recent decades but literature from low-income countries is very scarce. Moreover, prophylaxis guidelines have recently changed and the impact on IE incidence is still unknown.

RECENT FINDINGS

In high-income countries, the proportion of IE related to prior rheumatic disease has decreased significantly and has been replaced proportionally by cases related to degenerative valvulopathies, prosthetic valves, and cardiovascular implantable electronic devices. Nosocomial and non-nosocomial-acquired cases have risen, as has the proportion caused by staphylococci, and the median age of patients. In low-income countries, in contrast, rheumatic disease remains the main risk factor, and streptococci the most frequent causative agents. Studies performed to evaluate impact of guidelines changes' have shown contradictory results. The increased complexity of cases in high-income countries has led to the creation of IE teams, involving several specialties. New imaging and microbiological techniques may increase sensitivity for diagnosis and detection of IE cases. In low-income countries, IE remained related to classic risk factors. The consequences of prophylaxis guidelines changes are still undetermined.

Pseudomonas aeruginosa Infective Endocarditis Following Aortic Valve Implantation: A Note of Caution

Transcatheter aortic valve implantation (TAVI) is an alternative treatment for severe aortic valve stenosis (AS) in patients with prohibitive risk for surgical aortic valve replacement (SAVR). Prosthetic valve endocarditis (PVE) is a rare complication of this relatively novel procedure and current guidelines do not include specific recommendations for its treatment.

We report a case of PVE due to Pseudomonas aeruginosa after TAVI that required SAVR, with successful outcome.

PVE usually occurs during the first year after TAVI and entails a high mortality risk because patients eligible for this min-imally invasive procedure are fragile (i.e. advanced age and/or severe comorbidities). Additionally, clinical presentation may be atypical or subtle and transesophageal echocardiogram (TEE) may not be conclusive, which delays diagnosis and treatment worsening the prognosis. This case highlights that open SAVR might be ultimately indicated as part of treatment for TAVI-PVE despite a high-risk surgery score.

Managing infective endocarditis in the elderly: new issues for an old disease

The incidence of infective endocarditis (IE) rises in industrialized countries. Older people are more affected by this severe disease, notably because of the increasing number of invasive procedures and intracardiac devices implanted in these patients. Peculiar clinical and echocardiographic features, microorganisms involved, and prognosis of IE in elderly have been underlined in several studies. Additionally, elderly population appears quite heterogeneous, from healthy people without past medical history to patients with multiple diseases or who are even bedridden. However, the management of IE in this population has been poorly explored, and international guidelines do not recommend adapting the therapeutic strategy to the patient's functional status and comorbidities. Yet, if IE should be treated according to current recommendations in the healthiest patients, concerns may rise for older patients who suffer from several chronic diseases, especially renal failure, and are on polypharmacy. Treating frailest patients with high-dose intravenous antibiotics during a prolonged hospital stay as recommended for younger patients could also expose them to functional decline and toxic effect. Likewise, the place of surgery according to the aging characteristics of each patient is unclear. The aim of this article is to review the recent data on epidemiology of IE and its peculiarities in the elderly. Then, its management and various therapeutic approaches that can be considered according to and beyond guidelines depending on patient comorbidities and frailty are discussed.