Infective endocarditis: innovations in the management of an old disease

Percutaneous aspiration of aortic valve vegetation in a patient with aortic valve endocarditis

Key Clinical Message

Percutaneous aspiration for debulking of vegetations in right-sided infective endocarditis has been well-described, however, this technique can be employed successfully for left-sided vegetations in select high-risk patients.

Abstract

We report a case of percutaneous aspiration of an aortic valve vegetation in a patient with prosthetic valve endocarditis. This novel approach was selected after patient declined surgical intervention for an enlarging vegetation despite antibiotic therapy. The procedure was successful, resulting in the complete removal of solid vegetation without complications.

A Contemporary Review of the Use of Extracorporeal CytoSorb® Hemoadsorption Therapy in Patients with Infective Endocarditis

Infective endocarditis (IE) is a rare but severe disease with high morbidity and mortality. Cardiac surgery plays a major role in the contemporary clinical management of IE patients. During cardiac surgery, cardiopulmonary bypass significantly contributes to an increased risk of organ dysfunction and mortality by inducing an acute inflammatory response, vascular endothelial cell injury, impairment of the coagulation cascade, and ischemia-reperfusion injury. During the past decade, the use of extracorporeal hemoadsorption therapy with the CytoSorb® hemoadsorber (CytoSorbents Europe GmbH, Berlin, Germany) has been proposed as an adjuvant therapy to mediate inflammatory responses in IE patients undergoing cardiac surgery with cardiopulmonary bypass. However, there is currently no systematic evaluation of the effect of CytoSorb® hemoadsorption on clinical outcomes such as hemodynamics, organ dysfunction, and mortality in patients with IE. Therefore, in this review, we exclusively discuss contemporary findings concerning the rationale, clinical evidence, and future perspectives for CytoSorb® hemoadsorption therapy in IE patients.

Prosthetic Valve Endocarditis After Aortic Valve Replacement With Bovine Versus Porcine Bioprostheses

BACKGROUND

Whether a bovine or porcine aortic valve bioprosthesis carries a higher risk of endocarditis after aortic valve replacement is unknown. The aim of this study was to compare the risk of prosthetic endocarditis in patients undergoing aortic valve replacement with a bovine versus porcine bioprosthesis.

METHODS AND RESULTS

This nationwide, population-based cohort study included all patients who underwent surgical aortic valve replacement with a bovine or porcine bioprosthesis in Sweden from 1997 to 2018. Regression standardization was used to account for intergroup differences. The primary outcome was prosthetic valve endocarditis, and the secondary outcomes were all-cause mortality and early prosthetic valve endocarditis. During a maximum follow-up time of 22 years, we included 21 022 patients, 16 603 with a bovine valve prosthesis and 4419 with a porcine valve prosthesis. The mean age was 73 years, and 61% of the patients were men. In total, 910 patients were hospitalized for infective endocarditis: 690 (4.2%) in the bovine group and 220 (5.0%) in the porcine group. The adjusted cumulative incidence of prosthetic valve endocarditis at 15 years was 9.5% (95% CI, 6.2%-14.4%) in the bovine group and 2.8% (95% CI, 1.4%-5.6%) in the porcine group. The absolute risk difference between the groups at 15 years was 6.7% (95% CI, 0.8%-12.5%).

CONCLUSIONS

The risk of endocarditis was higher in patients who received a bovine compared with a porcine valve prosthesis after surgical aortic valve replacement. This association should be considered in patients undergoing both surgical and transcatheter aortic valve replacement.

ASSESS-IE: a Novel Risk Score for Patients with Infective Endocarditis

Mortality in patients with infective endocarditis (IE) remains high. The existing risk scores are relatively complex with limited clinical application. This study was conducted to establish a new risk model to predict in-hospital and 6-month mortality in IE patients. A total of 1549 adult patients with definite IE admitted to Guangdong Provincial People's Hospital (n=1354) or Xiamen Cardiovascular Hospital (n=195) were included. The derivation cohort consisted of 1141 patients. The score was developed using the multivariate stepwise logistic regression analysis for in-hospital death. Bootstrap analysis was used for validation. Discrimination and calibration were evaluated by the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit test. Six risk factors were used as score parameters (1 point for each): aortic valve affected, previous valve replacement surgery, severe heart failure, elevated serum direct bilirubin, moderate-severe anemia and acute stage. The predictive value and calibration of the ASSESS-IE score for in-hospital death were excellent in the derivation (area under the curve [AUC]=0.781, p<0.001; Hosmer-Lemeshow p=0.948) and validation (AUC=0.779, p<0.001; Hosmer-Lemeshow p=0.520) cohorts. The score remained excellent in bootstrap validation (AUC=0.783). The discriminatory ability of the ASSESS-IE score for in-hospital (AUC: 0.781 vs. 0.799, p=0.398) and 6-month mortality (AUC: 0.778 vs. 0.814, p=0.040) were similar with that of Park's score which comprised 14 variables. The ASSESS-IE risk score is a new and robust risk-stratified tool for patients with IE, which might further facilitate clinical decision-making.

International Survey on Perioperative Management of Patients With Infective Endocarditis

OBJECTIVES

To estimate the current practice in the perioperative management of patients undergoing cardiac surgery due to infective endocarditis.

DESIGN

A prospective, open, 24-item, web-based cross-sectional survey.

SETTING

Online survey endorsed by the European Association of Cardiothoracic Anesthesiology and Intensive Care (EACTAIC).

PARTICIPANTS

Members of the EACTAIC.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 156 responses from 44 countries were received, with a completion rate of 99%. The response rate was 16.6%. Most respondents (76%) practiced cardiac anesthesia in European hospitals, and most respondents stated that a multidisciplinary endocarditis team was not established at their center, that cardiac anesthesiologists appeared to be involved infrequently in those teams (36%), and that they were not involved in decision-making on indication and timing of surgery (88%). In contrast, the cardiac anesthesiologist performed intraoperative antibiotic therapy (62%) and intraoperative transesophageal echocardiography (90%). Furthermore, there was a relative heterogeneity concerning perioperative monitoring, as well as for coagulation and transfusion management.

CONCLUSIONS

This international survey evaluated current practice among cardiac anesthesiologists in the perioperative management of patients with infective endocarditis and the anesthesiologist's role in multidisciplinary decision-making. Heterogeneity in treatment approaches was identified, indicating relevant knowledge gaps that should encourage further clinical research to optimize treatment and postoperative outcomes in this specific population.

Real world experience of therapeutic monitoring of medically treated prosthetic valve infective endocarditis by 18F-FDG-PET/CT

INTRODUCTION

18F-FDG-PET/CT is recommended to improve the diagnosis of prosthetic valve infective endocarditis (PVIE) and is a major criterion in the ESC-2015 classification. However, there is little evidence for its usefulness in the follow-up of medically treated PVIE patients.

METHODS

A monocentric retrospective analysis of patients hospitalized for PVIE between January 2013 and December 2019 who were not treated with surgery and who had at least two 18F-FDG-PET/CT examinations during their medical management.

RESULTS

Among 170 patients with PVIE, 117 were treated with antibiotic therapy but no surgery. Of these, 36 (31%) had at least two 18F-FDG-PET/CT examinations. At initial imaging, 28 patients had heterogeneous FDG uptake on their prosthetic valve and eight on their associated aortic graft. Hypermetabolism of spleen and bone marrow (HSBM) was observed in 18 and 19 patients, respectively. At the first follow-up 18F-FDG-PET/CT, 21 (58%) patients still had heterogeneous uptake, indicating persistent active endocarditis. HSBM was still present at the last follow-up imaging in four of the six patients with recurrent PVIE.

CONCLUSION

18F-FDG-PET/CT monitoring of medically treated patients with PVIE provides valuable additional information and prospective multicentric study should be conducted to assess its usefulness.

Management of anticoagulation in patients with infective endocarditis

Infective endocarditis (IE) carries a high risk of vascular complications (e.g., cerebral embolism, intracerebral hemorrhage, and renal infarction), which are correlated with increased early and late mortality. Although anticoagulation is the cornerstone for management of thromboembolic complications, it remains controversial and challenging in patients with IE. An appropriate anticoagulation strategy is crucial to improving outcomes and requires a good understanding of the indication, timing, and regimen of anticoagulation in the setting of IE. Observational studies have shown that anticoagulant treatment failed to reduce the risk of ischemic stroke in patents with IE, supporting that IE alone is not an indication for anticoagulation. In the absence of randomized controlled trials and high-quality meta-analyses, however, current guidelines on IE were based largely on observational data and expert opinion, providing few specific recommendations on anticoagulation. A multidisciplinary approach and patient engagement are required to determine the timing and regimen of anticoagulation in patients with IE, especially in specific situations (e.g., receiving warfarin anticoagulation at the time of IE diagnosis, cerebral embolism or ischemic stroke, intracerebral hemorrhage, or urgent surgery). Collectively, individualized strategies on anticoagulation management of IE should be based on clinical evaluation, available evidence, and patient engagement, and ultimately be developed by the multidisciplinary team.

Commensal Streptococcal Infective Endocarditis of the Native Mitral Valve in a Transcatheter Aortic Valve Replacement (TAVR) Patient: A Heartful, a Handful, and a Mouthful

An 88-year-old woman with an extensive medical history presented to the hospital with altered mental status, vague abdominal pain, and dysuria. A previous transcatheter aortic valve replacement (TAVR) prosthesis was known to be failing and was suspected to have acquired a vegetation. No other infective endocarditis (IE) stigmata were present. Fortunately, the work-up for replacement was allowed to proceed with a broader cardiac examination from which a mitral vegetation was identified and IE then treated.

Application of metagenomic next-generation sequencing in patients with infective endocarditis

Objectives

Metagenomic next-generation sequencing (mNGS) technology is helpful for the early diagnosis of infective endocarditis, especially culture-negative infective endocarditis, which may guide clinical treatment. The purpose of this study was to compare the presence of culture-negative infective endocarditis pathogens versus culture-positive ones, and whether mNGS test results could influence treatment regimens for patients with routine culture-negative infective endocarditis.

Methods

The present study enrolled patients diagnosed with infective endocarditis and tested for mNGS in the First Affiliated Hospital of Zhengzhou University from February 2019 to February 2022 continuously. According to the culture results, patients were divided into culture-negative group (Group CN, n=18) and culture-positive group (Group CP, n=32). The baseline characteristics, clinical data, pathogens, 30 day mortality and treatment regimen of 50 patients with infective endocarditis were recorded and analyzed.

Results

Except for higher levels of PCT in the Group CN [0.33 (0.16-2.74) ng/ml vs. 0.23 (0.12-0.49) ng/ml, P=0.042], there were no significant differences in the basic clinical data and laboratory examinations between the two groups (all P>0.05). The aortic valve and mitral valve were the most involved valves in patients with infective endocarditis (aortic valve involved: Group CN 10, Group CP 16; mitral valve involved: Group CN 8, Group CP 21; P>0.05) while 9 patients had multiple valves involved (Group CN 2, Group CP 7; P>0.05). The detection rate of non-streptococci infections in the Group CN was significantly higher than that in the Group CP (9/18 vs. 3/32, P=0.004). There was no significant difference in patients with heart failure hospitalization and all-cause death at 30 days after discharge (3 in Group CN vs. 4 in Group CP, P>0.05). It is worth noting that 10 patients with culture-negative infective endocarditis had their antibiotic regimen optimized after the blood mNGS.

Conclusions

Culture-negative infective endocarditis should be tested for mNGS for early diagnosis and to guide clinical antibiotic regimen.

Impact of the Duration of Postoperative Antibiotics on the Prognosis of Patients with Infective Endocarditis

Appropriate postoperative antibiotic treatment in patients with infective endocarditis (IE) reduces the risks of recurrence and mortality. However, concerns about adverse drug reactions arise due to prolonged antibiotic usage. Therefore, we compared the recurrence and mortality rates according to the duration of postoperative antibiotic therapy in patients with IE. From 2005 to 2017, we retrospectively reviewed 416 patients with IE treated at a tertiary hospital in South Korea; among these, 216 patients who underwent heart valve surgery and received appropriate antibiotics were enrolled. The patients were divided into two groups based on the duration of usage of postoperative antibiotic therapy; the duration of postoperative antibiotic therapy was more than two weeks in 156 patients (72.2%) and two weeks or less in 60 patients (27.8%). The primary endpoint was IE relapse. The secondary endpoints were 1-year IE recurrence, 1-year mortality, and postoperative complication rates. The median age was 53 (interquartile range: 38-62) years. The relapse rate of IE was 0.9% (2/216). There was no statistical difference in relapse (0.0% vs. 1.3%, p = 0.379), 1-year recurrence (1.7% vs. 1.3%, p = 0.829), or 1-year mortality (10.0% vs. 5.8%, p = 0.274) between patients with postoperative antibiotic administration of two weeks or less versus more than two weeks. The duration of postoperative antibiotic therapy did not affect the 1-year mortality rate (log-rank test, p = 0.393). In conclusion, there was no statistically significant difference in recurrence, mortality, or postoperative complications according to the duration of postoperative antibiotic therapy.

Strengths and limitations of patient registries in infective endocarditis

BACKGROUND

Infective endocarditis (IE) is a serious albeit relatively infrequent disease. Given the paucity of cases, particularly in non-referral centres, patient registries have progressively gained relevance to inform about the epidemiology, clinical presentation, and natural history of IE in the last two decades. Although they have become key to advancing knowledge of IE, registries also have shortcomings that lead to relevant consequences that are often overlooked.

OBJECTIVES

We aimed to discuss the strengths and limitations of registries in IE.

SOURCES

We conducted a PubMed search of relevant articles published between January 2000 and June 2022.

CONTENT

The backbone of the contemporary knowledge on IE has been built upon data collected in prospective registries, which has allowed us to collect data on relatively unknown aspects of the disease, identify knowledge gaps, and generate new hypotheses, serving as platforms for further research endeavours. Well-exploited registries can provide key information on how IE is distributed across populations and how it differentially impacts patients and subgroups. However, registries face several difficulties, such as the definition of IE, which includes subjective variables and changes over time. Other limitations include difficulty achieving a comprehensive collection of cases (which depends on both project funding and information systems), over-representation of the centres that created the registry, lack of inclusion of variables to assess endpoints that are relevant to patients in terms of quality of life and prognosis, and ethical issues.

IMPLICATIONS

The review of the advantages and disadvantages of registries aims to improve the quality of the information collected, the viability of the registry itself, and the ability to answer questions that are relevant to both researchers and patients.

The clinical pattern differentiates ANCA-positive infective endocarditis patients from ANCA-associated vasculitis patients: a 23 years' retrospective cohort study in China and follow-ups

Objectives

Patients with infective endocarditis (IE) may present rheumatic manifestations concurrent with various autoantibodies and thus mimic antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). This study aims to characterize the specific features in a long-term cohort of ANCA-positive IE patients and to perform comparative analysis with primary AAV patients.

Methods

We performed a retrospective thorough review of 475 consecutive IE patients over 23 years, identifying 22 patients positive for proteinase 3 and/or myeloperoxidase and 36 treatment-naïve AAV patients. The clinical, laboratory, and follow-up data were collected to perform comparative analysis.

Results

Our study illustrated that ANCA-positive IE patients were younger and had a shorter duration than AAV patients. Pulmonary lesions, ENT signs, peripheral neuropath, and proteinuria were more commonly seen in AAV patients, while heart valve involvement, spleen enlargement, and cerebral hemorrhage were more typical for IE patients (all p < 0.05). Besides, ANCA-positive IE patients presented a higher level of PR3-ANCA but lower C3 (both p < 0.05). Hyperleukocytosis and thrombocytopenia were more frequently found in AAV patients (both p < 0.05). No significant difference was noticed in the survival rate.

Conclusions

Our study urges the early differential diagnosis of IE in ANCA-positive patients. It supports the claim that ANCA-positive IE patients and AAV patients do not share the same clinical spectrum. Echocardiography, serological profiles, and evaluation of multi-organ involvement might be required to improve diagnostic accuracy.

Key Points •Early differential diagnosis of ANCA-positive IE from AAV is challenging even for expert rheumatologists. •Our study is so far one of the largest to include 22 ANCA-positive IE patients in one single center and spanning over 23 years. It is also the first study to include both ANCA-positive IE patients and AAV patients in one center. •Our study aides to identify a clinical picture to differentiate ANCA-Positive IE Patients from AAV Patients.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10067-022-06313-w.

Sex Differences in Characteristics of Patients with Infective Endocarditis: A Multicenter Study

Infectious diseases like infective endocarditis (IE) may manifest or progress differently between sexes. This study sought to identify the differences in demographic and clinical characteristics among male and female patients with IE. Data were obtained from a newly developed registry comprising all adult patients with first IE admission at the four major tertiary cardiovascular centers in West Virginia, USA during 2014−2018. Patient characteristics were compared between males and females using Chi-square test, Fisher’s exact test, and Wilcoxon rank-sum test. A secondary analysis was restricted to IE patients with drug use only. Among 780 unique patients (390 males, 390 females), significantly more women (a) were younger than males (median age 34.9 vs. 41.4, p < 0.001); (b) reported drug use (77.7% vs. 64.1%, p < 0.001); (c) had tricuspid valve endocarditis (46.4% vs. 30.8%, p < 0.001); and (d) were discharged against medical advice (20% vs. 9.5%, p < 0.001). These differences persisted even within the subgroup of patients with drug use-associated IE. In a state with one of the highest incidences of drug use and overdose deaths, the significantly higher incident IE cases in younger women and higher proportion of women leaving treatment against medical advice are striking. Differential characteristics between male and female patients are important to inform strategies for specialized treatment and care.

Anesthesia Considerations in Infective Endocarditis

The management of infective endocarditis is complex and inherently requires multidisciplinary cooperation. About half of all patients diagnosed with infective endocarditis will meet the criteria to undergo cardiac surgery, which regularly takes place in urgent or emergency settings. The pathophysiology and clinical presentation of infective endocarditis make it a unique disorder within cardiac surgery that warrants a thorough understanding of specific characteristics in the perioperative period. This includes, among others, echocardiography, coagulation, bleeding management, or treatment of organ dysfunction. In this narrative review article, the authors summarize the current knowledge on infective endocarditis relevant for the clinical anesthesiologist in perioperative management of respective patients. Furthermore, the authors advocate for the anesthesiologist to become a structural member of the endocarditis team.

Infective endocarditis following COVID-19 pneumonia: about two cases

Coronavirus disease 2019 (COVID-19) has emerged as a pandemic and public health crisis across the world. The severity of this situation is escalating in certain populations, particularly when the COVID-19 diagnosis may delay the recognition of more dramatic illnesses such as infective endocarditis, which is a dreaded complication in patients with cardiac disease. We report the case of two patients who presented with infective endocarditis initially mistaken for COVID-19 pneumonia, which was responsible for a delay in diagnosis. We discuss the diagnostic difficulties as well as the management of this complication in the COVID-19 era. As a physician, one must remain alert to this dreaded complication, especially in patients with a cardiac history, in order to prevent it, detect it early, and manage it in time.

The clinical value of valve metagenomic next-generation sequencing when applied to the etiological diagnosis of infective endocarditis

Background

Metagenomic next-generation sequencing (mNGS) is widely applied in the etiological diagnosis of infectious diseases. However, the clinical practice of mNGS in infective endocarditis (IE) is relatively less studied. This research aimed to assess the etiological diagnostic value of valve mNGS in IE.

Methods

We retrospectively analyzed 49 IE patients who underwent cardiac valve surgery in Zhongshan Hospital, Fudan University, Shanghai from 1 June 2018 to 30 November 2020. Among these IE patients, 28 were culture positive and 21 were culture negative. The culture results of the culture-positive IE patients were set as gold standard to assess the sensitivity and specificity of valve mNGS in the etiological diagnosis of IE. We studied the positive detection rate of pathogens by valve mNGS among the culture-negative IE patients. During the same period, we also collected the resected valves of 8 patients with non-infective valvular diseases for mNGS as negative controls.

Results

The valve mNGS results of the culture-positive IE patients were the exact same as their culture results. Both the sensitivity and specificity of valve mNGS were 100%. The positive detection rate of pathogens by valve mNGS was 100% among the culture-negative IE patients. The stringent mapped reads number of genera (SMRNG), relative abundance of genera, stringent mapped reads number of species (SMRN), relative abundance of species, and coverage rate of valve mNGS results were significantly higher in culture-positive IE participants than in culture-negative IE participants. The valve mNGS results of the 8 participants with non-infective valvular diseases were all negative.

Conclusions

Valve mNGS is a promising technology for the etiological diagnosis of IE, especially culture-negative IE, and it may be used to guide precise antibiotic treatment after surgery.

Long term outcomes in patients with RF/RHD: Eight-year follow-up of HP-RF/RHD (Himachal Pradesh Rheumatic Fever/Rheumatic Heart Disease) registry in a Northern Indian state

BACKGROUND

The long-term outcome data in patients with rheumatic fever/rheumatic heart disease (RF/RHD) is limited. We report the cumulative incidence of adverse outcomes in a cohort of RHD patients from a northern state of India at a median follow-up of 5.4 years.

METHODS

1714 patients with RF/RHD diagnosed using clinical and echocardiographic criteria were registered from 2011 to 2018, and their baseline clinical characteristics and treatment practices were recorded. Patients were followed up annually for a median of 5.4 years (range 1-8 years) for incident adverse outcomes. The cumulative incidence of adverse composite outcomes, all-cause mortality, hospitalization for heart failure, stroke, and/or peripheral embolism was estimated. The baseline clinical characteristics were explored to identify the potential risk predictors using a multivariate cox proportional hazard model.

RESULTS

The cumulative incidence of adverse composite outcomes was 17.1% (15.3%-19.0%) at a median follow-up of 5.4 years. The predictors for the adverse composite outcomes (hazard ratio, 95% confidence interval) were age (1.03, 1.02-1.04), education status below primary level (1.60, 1.23-2.05), severe valvular heart disease (1.74, 1.36-2.23), NYHA class III/IV at enrollment (1.56, 1.18-2.07), right heart failure (4.48, 2.85-6.95), history of stroke and/or peripheral embolism (3.7, 1.5-9.2) and mitral balloon valvuloplasty (0.62, 0.40-0.96).

CONCLUSIONS

The incidence of adverse outcomes is substantial in patients with RF/RHD. Thus, early detection of high-risk patients and their risk management is needed to improve outcomes.

Clinical and Microbiological Characteristics of Infective Endocarditis at a Cardiac Center in Saudi Arabia

BACKGROUND

Infective endocarditis (IE) is a serious disease with complex pathology and significant mortality. Little information is known regarding clinical and microbiological characteristics in Saudi Arabia. This study surveyed these characteristics at a Cardiac Center in Riyadh, Saudi Arabia over a period of 5 years.

METHODS

This retrospective study was done on all infective endocarditis (IE) patients admitted to Prince Sultan Cardiac Center between January 1, 2015, and December 31, 2019. Clinical characteristics, microbiological results, management, and outcomes were assessed.

RESULT

A total of 340 cases of infective endocarditis were identified over the study period. Most patients (64%) were 50 years old or above, and 67% were males. Fever was the most common clinical presentation, and a murmur was audible in a fifth of patients. Blood cultures were positive in 177 (52%) cases. The most common organisms were Staphylococcus aureus, coagulase negative Staphylococcus and viridans group Streptococcus. Most common microbiological organisms causing native valve endocarditis were viridans group Streptococcus (32%) followed by methicillin-susceptible Staphylococcus aureus (21%), and for prosthetic valve endocarditis they were coagulase negative Staphylococcus (32%) followed by methicillin-susceptible Staphylococcus aureus (23%), the most common causes of culture negative endocarditis were Q-fever and brucellosis. Predisposing cardiac conditions were present in 127 (37%) patients, most commonly rheumatic heart disease and congenital heart disease. Surgical intervention was done in 26% of cases, with an overall in-hospital mortality rate of 6.76%.

CONCLUSION

We demonstrate the epidemiological, clinical, and microbiological profile of infective endocarditis in a tertiary care cardiac center in Saudi Arabia. It gives information concerning the prevalence of responsible organisms. This information will be helpful in assessing patients with suspected IE and in planning management of cases knowing the relative frequency of types of microorganisms encountered.

[Artificial Intelligence and teleradiology in cardiovascular imaging by CT-Scan and MRI]

Cardiac CT-Scan and cardiac magnetic resonance imaging (MRI) are two booming cardiac imaging modalities especially in chest pain screening for CT-Scan and in surveillance of patients with known coronary artery disease for MRI. Artificial Intelligence is already of great help in radiologic diagnosis and its use should widen in the next few years. Teleradiology allows remote interpretation of all radiology exams and should develop in cardiac imaging. Expert radiology diagnosis centers should develop gathering cardiologists and radiologists with great experience in the field of cardiac imaging interpretation. Peripheral acquisition radiology centers would be disseminated all across the country without a need for a local expert and would send their images to the expert center for interpretation. The expert center would be the middle of this spider web, sending back the report and the selected images to the peripheral center, allowing optimal care for all patients nationwide. Artificial Intelligence would be a major asset of these expert centers, improving through the years. This operating mode would allow the onset of systematic screening for coronary artery disease in the global population and the surveillance of known coronary artery disease treated patients.

RexAB promotes the survival of Staphylococcus aureus exposed to multiple classes of antibiotics

Antibiotics inhibit essential bacterial processes, resulting in arrest of growth and, in some cases, cell death. Many antibiotics are also reported to trigger endogenous production of reactive oxygen species (ROS), which damage DNA, leading to induction of the mutagenic SOS response associated with the emergence of drug resistance. However, the type of DNA damage that arises and how this triggers the SOS response are largely unclear. We found that several different classes of antibiotic triggered dose-dependent induction of the SOS response in Staphylococcus aureus, indicative of DNA damage, including some bacteriostatic drugs. The SOS response was heterogenous and varied in magnitude between strains and antibiotics. However, in many cases, full induction of the SOS response was dependent upon the RexAB helicase/nuclease complex, which processes DNA double-strand breaks to produce single-stranded DNA and facilitate RecA nucleoprotein filament formation. The importance of RexAB in repair of DNA was confirmed by measuring bacterial survival during antibiotic exposure, with most drugs having significantly greater bactericidal activity against rexB mutants than against wild-type strains. For some, but not all, antibiotics there was no difference in bactericidal activity between wild type and rexB mutant under anaerobic conditions, indicative of a role for reactive oxygen species in mediating DNA damage. Taken together, this work confirms previous observations that several classes of antibiotics cause DNA damage in S. aureus and extends them by showing that processing of DNA double-strand breaks by RexAB is a major trigger of the mutagenic SOS response and promotes bacterial survival.

Dentists' practice and compliance with current guidelines of infective endocarditis prophylaxis- National survey study

Background

The objective of this study was to assess the attitude, practice, and knowledge of Croatian dentists regarding infective endocarditis (IE) prophylaxis.

Material and Methods

A cross-sectional, self-reporting questionnaire survey was conducted with the participation of 348 Croatian dentists. The questionnaire was designed to collect information on participants’ work experience, place of work, their attitudes related to the treatment of IE-risk patients, knowledge and adherence to IE antibiotic prophylaxis guidelines.

Results

Knowledge and adherence to the current guidelines decreased with the higher years of experience. Compliance with the current guidelines varied, mostly because of respondents’ insecurity regarding which guidelines to follow. AHA guidelines have been most frequently the first choice (25% participants). Surprisingly, 23% of dentists didn’t follow any of the official guidelines. The majority of participants (68%) have declared a lack of preparedness or willingness to treat the patients at risk of IE. Dentists with specialty or working at university/hospital have shown a higher level of knowledge and preparedness to treat IE-risk patients.

Conclusions

The lack of knowledge of guidelines and consequent inconsistencies in IE antibiotic prophylaxis in Croatian dental practice indicates the need for urgent improvement.

Key words:Antibiotic prophylaxis, dentistry, infective endocarditis.

Infective Endocarditis: A Focus on Oral Microbiota

Infective endocarditis (IE) is an inflammatory disease usually caused by bacteria entering the bloodstream and settling in the heart lining valves or blood vessels. Despite modern antimicrobial and surgical treatments, IE continues to cause substantial morbidity and mortality. Thus, primary prevention and enhanced diagnosis remain the most important strategies to fight this disease. In this regard, it is worth noting that for over 50 years, oral microbiota has been considered one of the significant risk factors for IE. Indeed, among the disparate recommendations from the American heart association and the European Society of Cardiology, there are good oral hygiene and prophylaxis for high-risk patients undergoing dental procedures. Thus, significant interest has grown in the role of oral microbiota and it continues to be a subject of research interest, especially if we consider that antimicrobial treatments can generate drug-resistant mutant bacteria, becoming a severe social problem. This review will describe the current knowledge about the relationship between oral microbiota, dental procedures, and IE. Further, it will discuss current methods used to prevent IE cases that originate from oral pathogens and how these should be focused on improving oral hygiene, which remains the significant persuasible way to prevent bacteremia and systemic disorders.

Ultrastructural mitral valve abnormalities in infective endocarditis

Aim. Using an original method based on backscattered scanning electron microscopy, to study the structural features of the mitral valve leaflets in infective endocarditis.

Material and methods. We examined 9 mitral valves extracted during surgical interventions due to structural malfunction in patients with infective endocarditis (IE). The samples were fixed in buffered paraformaldehyde with osmium tetraoxide postfixation. After dehydration by increasing alcohol concentration and acetone, the samples were placed in epoxy resin. After the resin has polymerized, the samples were ground and then polished to the desired depth. To increase the electronic contrast, the samples were treated with a uranyl acetate alcohol solution during dehydration and with Reynolds' lead citrate after polishing the epoxy blocks. The samples were visualized by backscattered scanning electron microscopy at an accelerating 15-kV voltage.

Results. Structural leaflet injuries caused by IE were most pronounced in the central part and the base. Necrotic areas were extensive electron-dense formations located in the central leaflet layers, or displaced towards the ventricular surface. The electron-dense material in the necrotic area was poorly structured and contained individual cells and bacteria. Bacteria were also present outside the necrotic area. Necrotic areas were surrounded by a layer of a modified extracellular matrix, usually covered with a fibrin layer. Among the extracellular matrix fibers, the macrophages, smooth myocytes and fibroblasts was noted. The fibrin layer, in addition to these cells, contained a large number of blood vessels and was often covered with endothelium.

Conclusion. Infection of the mitral valve leaflets causes a simultaneous inflammatory response and regeneration activation. Without adequate regulatory factors, the processes of inflammation and connective tissue creation lead to structural and functional leaflet failure. Specific causes may be overgrowth of necrotic and inflammatory areas, edema and fiber orientation disorder, as well as leaflet rupture.

U-Shaped Association Between Serum Uric Acid and Short-Term Mortality in Patients With Infective Endocarditis

BACKGROUND

Increased uric acid (UA) levels have been reported to be associated with poor clinical outcomes in several conditions. However, the prognostic value of UA in patients with infective endocarditis (IE) is yet unknown.

METHODS

A total of 1,117 patients with IE were included and divided into two groups according to the current definition of hyperuricemia (UA>420 μmol/L in men and >360 μmol/L in women): hyperuricemia group (n=336) and normouricemia group (n=781). The association between the UA level and short-term outcomes were examined.

RESULTS

The in-hospital mortality was 6.2% (69/1117). Patients with hyperuricemia carried a higher risk of in-hospital death (9.8% vs. 4.6%, p=0.001). Hyperuricemia was not an independent risk factor for in-hospital death (adjusted odds ratio [aOR]=1.92, 95% confidence interval [CI]: 0.92-4.02, p=0.084). A U-shaped relationship was found between the UA level and in-hospital death (p<0.001). The in-hospital mortality was lower in patients with UA in the range 250-400 μmol/L. The aOR of in-hospital death in patients with UA>400 and <250 μmol/L was 3.48 (95% CI: 1.38-8.80, p=0.008) and 3.28 (95%CI: 1.27-8.51, p=0.015), respectively. Furthermore, UA>400 μmol/L (adjusted hazard ratio [aHR]=3.54, 95%CI: 1.77-7.07, p<0.001) and <250 μmol/L (aHR=2.23, 95%CI: 1.03-4.80, p=0.041) were independent risk factors for the 6-month mortality.

CONCLUSION

The previous definition of hyperuricemia was not suitable for risk assessment in patients with IE because of the U-shaped relationship between UA levels and in-hospital death. Low and high levels of UA were predictive of increased short-term mortality in IE patients.

Comparative Surgical Outcomes of Prosthetic and Native Valve Endocarditis

In the present study, the patterns and clinical outcomes of prosthetic valve endocarditis (PVE) surgery were analyzed as compared with native valve endocarditis (NVE). The proportion of PVE among surgical infective endocarditis increased gradually through the study period. Patients with PVE was characterized by old age and more extensive infective lesions. PVE group showed notably higher early and overall mortality, and valve reinfection as well. PVE carried significant perioperative risks, and was an independent risk factor of overall mortality.

Background and Objectives

As a consequence of a growing number of patients undergoing prosthetic heart valve replacement, the incidence of prosthetic valve endocarditis (PVE) has increased. The study aims to analyze patterns and outcomes of PVE surgery as compared with native valve endocarditis (NVE).

Methods

We enrolled 269 patients (aged 58.0±15.7 years) who underwent valve surgery for infective endocarditis (IE) between 2013 and 2019. Of these, 56 had PVE whereas remainder (n=213) had NVE. Clinical outcomes were compared and multivariable analyses were conducted to determine risk factors for mortality.

Results

The proportion of PVE among surgical IE gradually increased from 15.4% (11/71) in the first time-quartile to 29.5% (18/61) in the last time-quartile (p=0.055). PVE patients were older, and more commonly had aorto-mitral curtain involvement and abscess formation than NVE group. Early mortality was 14.3% and 6.1% in PVE and NVE group, respectively (p=0.049). Postoperatively, PVE group had higher incidences of low cardiac output syndrome (p=0.027), new-onset dialysis (p=0.006) and reoperation for bleeding (p=0.004) compared to NVE group, but stroke rates were comparable (p=0.503). During follow-up (648.8 patient-years), PVE group showed significantly higher risks of overall mortality (p<0.001), valve reinfection (p<0.001) and permanent pacemaker implantation (p<0.001) than NVE group. On multivariable analysis, PVE (hazard ratio, 2.67; 95% confidence interval, 1.40–5.07; p=0.003) along with age, chronic kidney disease, multi-valve involvement, and causative organisms of Staphylococcus aureus or fungus were independent risk factors of overall mortality.

Conclusions

PVE carried significant perioperative risks, and was an independent risk factor of overall mortality.

Anticipating the management of Streptococcus agalactiae infective endocarditis

A patient who presented after falling out of bed had signs of right-sided stroke, which, after imaging, was suspicious for embolism with cardiac origin. Further investigation revealed a large aortic valve vegetation with mild aortic insufficiency, and the patient eventually developed heart failure requiring surgical intervention. Infective endocarditis is slowly becoming more prevalent, and clinicians should have a high index of suspicion when patients present with common complications of this disease, such as valvular dysfunction, heart failure, or stroke. Early diagnosis has been shown to reduce time to appropriate antibiotic treatment and definitive care, which can lead to better outcomes.

The general stress response of Staphylococcus aureus promotes tolerance of antibiotics and survival in whole human blood

Staphylococcus aureus is a frequent cause of invasive human infections such as bacteraemia and infective endocarditis. These infections frequently relapse or become chronic, suggesting that the pathogen has mechanisms to tolerate the twin threats of therapeutic antibiotics and host immunity. The general stress response of S. aureus is regulated by the alternative sigma factor B (σB) and provides protection from multiple stresses including oxidative, acidic and heat. σB also contributes to virulence, intracellular persistence and chronic infection. However, the protective effect of σB on bacterial survival during exposure to antibiotics or host immune defences is poorly characterized. We found that σB promotes the survival of S. aureus exposed to the antibiotics gentamicin, ciprofloxacin, vancomycin and daptomycin, but not oxacillin or clindamycin. We also found that σB promoted staphylococcal survival in whole human blood, most likely via its contribution to oxidative stress resistance. Therefore, we conclude that the general stress response of S. aureus may contribute to the development of chronic infection by conferring tolerance to both antibiotics and host immune defences.

Current uses of chlorhexidine for management of oral disease: a narrative review

Objectives

Chlorhexidine (CHX) is a commonly used antiseptic mouthwash, used by dental practitioners and the public, due to its antimicrobial effects. The aim of this article was to provide a narrative review of current antimicrobial uses of CHX relevant to dentistry in the context of oral diseases, highlighting need for further studies to support its safe and appropriate use.

Study selection, data and sources

Randomised controlled trials, systematic reviews and national (UK and US) guidelines were consulted where available, with search terms for each subject category entered into MEDLINE, PubMed, Google Scholar and the Cochrane database.

Results

Some evidence existed to support adjunctive short-term use of CHX to manage dental plaque, and reduce clinical symptoms of gingivitis, dry socket, as well as reduce aerosolisation of bacteria. However, use must be weighed alongside the less desirable effects of CHX, including extrinsic staining of teeth, antimicrobial resistance to antiseptic agents and the rare, but fatal, allergic reactions to CHX. Conversely, evidence for the effectiveness of chlorhexidine to manage or prevent periodontitis, dental caries, necrotising periodontal diseases, peri-implantitis, and infections associated with extraction and aerosolised viruses remains less certain.

Conclusions

The use of CHX in dentistry and oral healthcare continues to be widespread and thus it is important that dental practitioners understand that, based on its differential mechanisms of action on different microbes, appropriate clinical and dental use of CHX should be oral disease specific. However, further scientific and clinical research is required before full recommendations can be made.

A Novel Approach for Detecting Unique Variations among Infectious Bacterial Species in Endocarditic Cardiac Valve Vegetation

Infectious endocarditis (IE) remains one of the deadliest heart diseases with a high death rate, generally following thrombo-embolic events. Today, therapy is based on surgery and antibiotic therapy. When thromboembolic complications in IE patients persist, this is often due to our lack of knowledge regarding the pathophysiological development and organization of cells in the vegetation, most notably the primordial role of platelets and further triggered hemostasis, which is related to the diversity of infectious microorganisms involved. Our objective was to study the organization of IE vegetations due to different bacteria species in order to understand the related pathophysiological mechanism of vegetation development. We present an approach for ultrastructural analysis of whole-infected heart valve tissue based on scanning electron microscopy and energy-dispersive X-ray spectroscopy. Our approach allowed us to detect differences in cell organization between the analyzed vegetations and revealed a distinct chemical feature in viridans Streptococci ones. Our results illustrate the benefits that such an approach may bring for guiding therapy, considering the germ involved for each IE patient.

A comparison of different antibiotic regimens for the treatment of infective endocarditis

BACKGROUND

Infective endocarditis is a microbial infection of the endocardial surface of the heart. Antibiotics are the cornerstone of treatment, but due to the differences in presentation, populations affected, and the wide variety of micro-organisms that can be responsible, their use is not standardised. This is an update of a review previously published in 2016.

OBJECTIVES

To assess the existing evidence about the clinical benefits and harms of different antibiotics regimens used to treat people with infective endocarditis.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase Classic and Embase, LILACS, CINAHL, and the Conference Proceedings Citation Index - Science on 6 January 2020. We also searched three trials registers and handsearched the reference lists of included papers. We applied no language restrictions.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) assessing the effects of antibiotic regimens for treating definitive infective endocarditis diagnosed according to modified Duke's criteria. We considered all-cause mortality, cure rates, and adverse events as the primary outcomes. We excluded people with possible infective endocarditis and pregnant women.

DATA COLLECTION AND ANALYSIS

Two review authors independently performed study selection, 'Risk of bias' assessment, and data extraction in duplicate. We constructed 'Summary of findings' tables and used GRADE methodology to assess the quality of the evidence. We described the included studies narratively.

MAIN RESULTS

Six small RCTs involving 1143 allocated/632 analysed participants met the inclusion criteria of this first update. The included trials had a high risk of bias. Three trials were sponsored by drug companies. Due to heterogeneity in outcome definitions and different antibiotics used data could not be pooled. The included trials compared miscellaneous antibiotic schedules having uncertain effects for all of the prespecified outcomes in this review. Evidence was either low or very low quality due to high risk of bias and very low number of events and small sample size. The results for all-cause mortality were as follows: one trial compared quinolone (levofloxacin) plus standard treatment (antistaphylococcal penicillin (cloxacillin or dicloxacillin), aminoglycoside (tobramycin or netilmicin), and rifampicin) versus standard treatment alone and reported 8/31 (26%) with levofloxacin plus standard treatment versus 9/39 (23%) with standard treatment alone; risk ratio (RR) 1.12, 95% confidence interval (CI) 0.49 to 2.56. One trial compared fosfomycin plus imipenem 3/4 (75%) versus vancomycin 0/4 (0%) (RR 7.00, 95% CI 0.47 to 103.27), and one trial compared partial oral treatment 7/201 (3.5%) versus conventional intravenous treatment 13/199 (6.53%) (RR 0.53, 95% CI 0.22 to 1.31). The results for rates of cure with or without surgery were as follows: one trial compared daptomycin versus low-dose gentamicin plus an antistaphylococcal penicillin (nafcillin, oxacillin, or flucloxacillin) or vancomycin and reported 9/28 (32.1%) with daptomycin versus 9/25 (36%) with low-dose gentamicin plus antistaphylococcal penicillin or vancomycin; RR 0.89, 95% CI 0.42 to 1.89. One trial compared glycopeptide (vancomycin or teicoplanin) plus gentamicin with cloxacillin plus gentamicin (13/23 (56%) versus 11/11 (100%); RR 0.59, 95% CI 0.40 to 0.85). One trial compared ceftriaxone plus gentamicin versus ceftriaxone alone (15/34 (44%) versus 21/33 (64%); RR 0.69, 95% CI 0.44 to 1.10), and one trial compared fosfomycin plus imipenem versus vancomycin (1/4 (25%) versus 2/4 (50%); RR 0.50, 95% CI 0.07 to 3.55). The included trials reported adverse events, the need for cardiac surgical interventions, and rates of uncontrolled infection, congestive heart failure, relapse of endocarditis, and septic emboli, and found no conclusive differences between groups (very low-quality evidence). No trials assessed quality of life.

AUTHORS' CONCLUSIONS

This first update confirms the findings of the original version of the review. Limited and low to very low-quality evidence suggests that the comparative effects of different antibiotic regimens in terms of cure rates or other relevant clinical outcomes are uncertain. The conclusions of this updated Cochrane Review were based on few RCTs with a high risk of bias. Accordingly, current evidence does not support or reject any regimen of antibiotic therapy for the treatment of infective endocarditis.

Infective endocarditis in French Polynesia: Epidemiology, treatments and outcomes

BACKGROUND

French Polynesia is a French overseas collectivity in the South Pacific Ocean, where data on infective endocarditis (IE) are lacking.

AIMS

To investigate the epidemiology and outcomes of IE in French Polynesia.

METHODS

All hospital records from consecutive patients hospitalized in Taaone Hospital, Tahiti, from 2015 to 2018, with an International Classification of Diseases, 10th revision, separation diagnosis of IE (I330), were reviewed retrospectively.

RESULTS

From 190 hospital charts reviewed, 105 patients with a final diagnosis of IE, confirmed according to the modified Duke criteria, were included. The median duration of follow-up was 71 days (interquartile range 18-163 days). The mean age was 55±17 years, and there were 68 men (65%). Thirty-five patients (33%) had a history of rheumatic carditis and 43 (41%) had a prosthetic valve. There were 40 (38%) cases of staphylococcal IE, 32 (30%) of streptococcal IE and six (6%) of enterococcal IE. Cardiogenic shock, septic shock and clinically relevant cerebral complications were strongly associated with death from any cause (hazard ratio [HR] 16.85, 95% confidence interval [CI] 5.45-52.05 [P<0.001]; HR 2.62, 95% CI 1.23-5.56 [P=0.01]; and HR 4.14, 95% CI 1.92-8.92 [P<0.001], respectively). Seventy-three patients (69%) had a theoretical indication for surgery, which was performed in 38 patients (36%). Lack of surgery when there was a theoretical indication was significantly associated with death (HR 6.93, 95% CI 3.47-13.83; P<0.0001).

CONCLUSIONS

The pattern of IE in French Polynesia differs from Western countries in many ways. Postrheumatic valvular disease remains the main underlying disease, and access to emergency heart surgery is still a challenge.