Alternative Cardiac Imaging Modalities to Echocardiography for the Diagnosis of Infective Endocarditis

Native Infective Endocarditis: A State-of-the-Art-Review

Native valve infective endocarditis (NVE) is a global phenomenon, defined by infection of a native heart valve and involving the endocardial surface. The causes and epidemiology of the disease have evolved in recent decades, with a doubling of the average patient age. A higher incidence was observed in patients with implanted cardiac devices that can result in right-sided infection of the tricuspid valve. The microbiology of the disease has also changed. Previously, staphylococci, which are most often associated with health-care contact and invasive procedures, were the most common cause of the disease. This has now been superseded by streptococci. While innovative diagnostic and therapeutic strategies have emerged, mortality rates have not improved and remain at 30%, which is higher than that for many cancer diagnoses. The lack of randomized trials and logistical constraints impede clinical management, and long-standing controversies such as the use of antibiotic prophylaxis persist. This state of the art review addresses clinical practice, controversies, and strategies to combat this potentially devastating disease. A multidisciplinary team will be established to provide care for patients with presumptive NVE. The composition of the team will include specialists in cardiology, cardiovascular surgery, and infectious disease. The prompt administration of combination antimicrobial therapy is essential for effective NVE treatment. Additionally, a meticulous evaluation of each patient is necessary in order to identify any indications for immediate valve surgery. With the intention of promoting a more comprehensive understanding of the procedural management of native infective endocarditis and to furnish clinicians with a reference, the current evidence for the utilization of distinct strategies for the diagnosis and treatment of NVE are presented.

Contemporary applications of multimodality imaging in infective endocarditis

INTRODUCTION

Infective endocarditis (IE) is an increasingly important condition with significant morbidity and mortality. With advancements in cardiovascular interventions including prosthetic valve implantation and utilization of intracardiac devices, the prevalence of IE is rising in the modern era. Early detection and management of this condition are critical.

AREAS COVERED

This review presents a contemporary review of the applications of multi-modality imaging in IE, taking a comparative approach of the various imaging modalities.

EXPERT OPINION

Transthoracic and transesophageal echocardiography are essential imaging modalities in establishing the diagnosis of IE, as well as evaluating for complications of IE. Other imaging modalities such as cardiac computed tomography and nuclear imaging play an important role as adjuvant imaging modalities for the evaluation of IE, particularly in prosthetic valve IE and cardiovascular implantable device associated IE. It is crucial to understand the strengths, weaknesses, and clinical application of each imaging modality, to improve the diagnosis, management, and outcomes of patients with IE.

Multimodality Imaging Diagnosis in Infective Endocarditis

Imaging is an important tool in the diagnosis and management of infective endocarditis (IE). Echocardiography is an essential examination, especially in native valve endocarditis (NVE), but its diagnostic accuracy is reduced in prosthetic valve endocarditis (PVE). The diagnostic ability is superior for transoesophageal echocardiography (TEE), but a negative test cannot exclude PVE. Both transthoracic echocardiography (TTE) and TEE can provide normal or inconclusive findings in up to 30% of cases, especially in patients with prosthetic devices. New advanced non-invasive imaging tests are increasingly used in the diagnosis of IE. Nuclear medicine imaging techniques have demonstrated their superiority over TEE for the diagnosis of PVE and cardiac implantable electronic device infective endocarditis (CIED-IE). Cardiac computed tomography angiography imaging is useful in PVE cases with inconclusive TTE and TEE investigations and for the evaluation of paravalvular complications. In the present review, imaging tools are described with their values and limitations for improving diagnosis in NVE, PVE and CIED-IE. Current knowledge about multimodality imaging approaches in IE and imaging methods to assess the local and distant complications of IE is also reviewed. Furthermore, a potential diagnostic work-up for different clinical scenarios is described. However, further studies are essential for refining diagnostic and management approaches in infective endocarditis, addressing limitations and optimizing advanced imaging techniques across different clinical scenarios.

Novel putative biomarkers for infective endocarditis by serum proteomic analysis: a comprehensive review of literature

Infective endocarditis (IE) is a challenging condition with high mortality. Prompt detection of IE has become essential for early and immediate management. The authors aimed to comprehensively review the existing literature on novel putative biomarkers for IE through serum proteomic analysis. The literature reveals high levels of N-terminal-pro-B-type natriuretic peptide (NT-proBNP) levels in IE with staphylococcal etiology, valvular lesions, and when combined with cardiac troponin I (cTnI), had a more significant value for risk stratification. A higher pro-ADM level, copeptin, NT-proBNP, and the monocyte-to-high-density lipoprotein cholesterol ratio (MHR) all impacted mortality during the hospital stay. The biomarker matrix metalloproteinase-9 was utilized to predict new-onset embolic events in patients, thus serving as a predictive marker. Procalcitonin was an important diagnostic marker in IE complicated with severe infection. Interleukin-6 (IL-6), Interleukin-8 (IL-8), Interferon-γ, cTnI, and NT-proBNP were also discovered to be useful as prognostic indicators. Early diagnosis and appropriate treatment are possible using antiphospholipid antibodies as a diagnostic test for definite IE. It is also concluded that antineutrophilic cytoplasmic antibody positive individuals with IE had a lengthier hospital stay. These noninvasive biomarkers can identify patients at risk and provide appropriate and early clinical management. NT-proBNP, Cystatin C, troponins, IL-6, IL-8, S100A11, and AQP9 are examples of possible markers that appear promising for further research. In conclusion, large-scale validation studies should study these biomarkers further to establish their use in clinical settings.

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.

Diagnostic Work-Up in Patients with Nonbacterial Thrombotic Endocarditis

Nonbacterial thrombotic endocarditis (NBTE) is a form of endocarditis that occurs in patients with predisposing conditions, including malignancies, autoimmune diseases (particularly antiphospholipid antibody syndrome, which accounts for the majority of lupus-associated cases), and coagulation disturbances for which the correlation with classical determinants is unclear. The condition is commonly referred to as "marantic", "verrucous", or Libman-Sacks endocarditis, although these are not synonymous, representing clinical-pathological nuances. The clinical presentation of NBTE involves embolic events, while local valvular complications, generally regurgitation, are typically less frequent and milder compared to infective forms of endocarditis. In the past, the diagnosis of NBTE relied on post mortem examinations, while at present, the diagnosis is primarily based on echocardiography, with the priority of excluding infective endocarditis through comprehensive microbiological and serological tests. As in other forms of endocarditis, besides pathology, transesophageal echocardiography remains the diagnostic standard, while other imaging techniques hold promise as adjunctive tools for early diagnosis and differentiation from infective vegetations. These include cardiac MRI and 18FDG-PET/CT, which already represents a major diagnostic criterion of infective endocarditis in specific settings. We will herein provide a comprehensive review of the current knowledge on the clinics and therapeutics of NBTE, with a specific focus on the diagnostic tools.

Multimodality Imaging in the Diagnosis of Prosthetic Valve Endocarditis: A Brief Review

Infective endocarditis is a common and treatable condition that carries a high mortality rate. Currently the workup of infective endocarditis relies on the integration of clinical, microbiological and echocardiographic data through the use of the modified Duke criteria (MDC). However, in cases of prosthetic valve endocarditis (PVE) echocardiography can be normal or non-diagnostic in a high proportion of cases leading to decreased sensitivity for the MDC. Evolving multimodality imaging techniques including leukocyte scintigraphy (white blood cell imaging), ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET), multidetector computed tomographic angiography (MDCTA), and cardiac magnetic resonance imaging (CMRI) may each augment the standard workup of PVE and increase diagnostic accuracy. While further studies are necessary to clarify the ideal role for each of these imaging techniques, nevertheless, these modalities hold promise in determining the diagnosis, prognosis, and care of PVE. We start by presenting a clinical vignette, then evidence supporting various modality strategies, balanced by limitations, and review of formal guidelines, when available. The article ends with the authors' summary of future directions and case conclusion.

Infective endocarditis: A contemporary update

Infective endocarditis (IE) remains a rare condition but one with high associated morbidity and mortality. With an ageing population and increasing use of implantable cardiac devices and heart valves, the epidemiology of IE has changed. Early clinical suspicion and a rapid diagnosis are essential to enable the correct treatment pathways to be accessed and to reduce complication and mortality rates. In the current review, we detail the latest guidelines for the evaluation and management of patients with endocarditis and its prevention.

ACR Appropriateness Criteria® Infective Endocarditis

Infective endocarditis can involve a normal, abnormal, or prosthetic cardiac valve. The diagnosis is typically made clinically with persistently positive blood cultures, characteristic signs and symptoms, and echocardiographic evidence of valvular vegetations or valvular complications such as abscess, dehiscence, or new regurgitation. Imaging plays an important role in the initial diagnosis of infective endocarditis, identifying complications, prognostication, and informing the next steps in therapy. This document outlines the initial imaging appropriateness of a patient with suspected infective endocarditis and for additional imaging in a patient with known or suspected infective endocarditis. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

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).

Diagnostic imaging in infective endocarditis: a contemporary perspective

INTRODUCTION

Infective endocarditis (IE) remains a diagnostic challenge. Prompt diagnosis is essential for accurate risk stratification and appropriate therapeutic decisions and surgical management. In recent years, the use of multimodal imaging has had a transformative effect on the diagnostic approach of IE in selected patients.

AREAS COVERED

This review assesses published literature on different imaging modalities for the diagnosis of IE published between 1 January 2009 and 1 February 2020. We illustrate the diagnostic approach to IE with three clinical cases.

EXPERT OPINION

Novel approaches to imaging for cardiac and extracardiac complications improve and individualize diagnosis, management, and prognosis in patients with suspected IE. The use of multimodal imaging should be guided by a multidisciplinary group of medical providers that includes infectious disease specialists, radiologists, cardiologists, and cardiothoracic surgeons.

Comparative Value of Cardiac CT and Transesophageal Echocardiography in Infective Endocarditis: A Systematic Review and Meta-Analysis

PURPOSE

To assess the comparative diagnostic accuracy of cardiac CT and transesophageal echocardiography (TEE) in the detection of valvular and perivalvular complications in infective endocarditis.

MATERIALS AND METHODS

PubMed and Embase databases were systematically searched until July 2019 for original articles published in English. Studies were included if (a) they used CT and/or TEE as an index test, (b) data were provided as infective endocarditis valvular complications (classified as abscess or pseudoaneurysm, vegetation, leaflet perforation, and paravalvular leakage), and (c) they used surgical findings as the reference standard.

RESULTS

Eight studies fulfilled the inclusion criteria. The sensitivity was higher for CT than TEE for abscess or pseudoaneurysm detection, 78% (95% confidence interval [CI]: 70%, 85%) (112 of 142) versus 69% (95% CI: 62%, 76%) (94 of 135) (P = .052) and increased to 87% (95% CI: 78%, 93%) (70 of 79) when restricted to multiphase CT studies, the difference being significant (P = .04). The sensitivity was significantly higher for TEE than CT for vegetation detection, 94% (95% CI: 92%, 96%) (363 of 383) versus 64% (95% CI: 57%, 70%) (151 of 237) (P < .001) and leaflet perforation detection, 81% (95% CI: 71%, 88%) (74 of 91) versus 41% (95% CI: 25%, 59%) (14 of 35) (P = .02).The sensitivity for paravalvular leakage was 69% (95% CI: 58%, 79%) (56 of 80) versus 44% (95% CI: 30%, 59%) (21 of 48) for TEE and CT, respectively (P = .27).

CONCLUSION

CT performs better than TEE in the detection of abscess or pseudoaneurysm whereas TEE gives superior results for vegetation detection, leaflet perforation, and paravalvular leakage.Supplemental material is available for this article.© RSNA, 2020.

Evaluation of failed prosthetic valves in the valve-in-valve era: Potential for utilizing positron emission tomography/computed tomography to recognize infective endocarditis

Bioprosthetic valve dysfunction was treated in the past with redo open heart surgery. The need to identify occult leaflet infection was not an important requirement as all valve tissue was removed during surgery. With the dramatic growth in transcatheter aortic valve replacement (TAVR) valve-in-valve (ViV) therapy, identification of occult infection is of major significance. TAVR should be rarely performed in infected prosthetic valves and the optimal approach should include open heart surgery and removal of infected tissue. With surgical implants, it can be challenging to distinguish infection from degeneration. The use of advanced imaging modalities, including 18F-fluorodeoxyglucose positron emission tomography/computed tomography, in the diagnosis of occult infection is emerging. We report the use of this imaging modality to identify or exclude endocarditis in patients with prosthetic valves who were candidates for ViV therapy.

Infective Endocarditis of the Aortic Valve Complicated by Aorta–To–Pulmonary Artery Fistula

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Aortopulmonary fistulas in IE are a cause of aorta–to–pulmonary connections.

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Other causes include PDA and ruptured sinus of Valsalva aneurysm.

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Continuous flow is seen in modified views of the pulmonary artery.

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Aortic valve involvement is common in IE with aortocavitary fistula formation.

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.

Characterization of Medical Professional Liability Risks Associated With Transesophageal Echocardiography

BACKGROUND

Medical claim data offer the possibility to improve patient care and mitigate liability. Although published analyses exist in cardiology, no information is available for transesophageal echocardiography (TEE). In this study, the authors reviewed medical claims involving TEE to identify potential risk management concerns so that these lessons could be used to improve the safety and quality of transesophageal echocardiographic practice.

METHODS

The authors reviewed anonymized clinical and claims data from all closed claims from 2008 to 2013 for a single national physician liability insurer.

RESULTS

There were no claims involving transthoracic echocardiography and eight involving TEE. Three claims involved esophageal perforation, a known risk of TEE. Two claims involved quadriplegia allegedly due to neck manipulation in the setting of a cervical spinal abscess that should have been suspected. Three claims involved the cardiologist's failure to diagnose endocarditis, with allegations that the cardiologist did not perform TEE in an appropriate time frame to avoid major morbidity and mortality from endocarditis.

CONCLUSIONS

Liability claims associated with TEE involve failure to order and perform TEE in an appropriate clinical scenario and in a timely manner; failure to properly document medical decision making; failure to inform patients regarding risks of TEE; failure to properly monitor the patient before, during, and after TEE; and technical difficulties in performing the procedure. Cardiologists should recognize guideline-based indications when TEE is needed and be mindful of the complication rates of this procedure. When screening a patient for TEE, consider expert input that may reduce the risks of TEE (e.g., a spine specialist for a neck injury, a gastroenterologist for esophageal comorbidity). Informed consent and medical record documentation should be practiced as a vehicle to inform patients of these risks and chronicle decision-making processes.

18F-FDG-PET/CT Imaging to Diagnose Septic Emboli and Mycotic Aneurysms in Patients with Endocarditis and Cardiac Device Infections

PURPOSE OF REVIEW

This review analyzes recent studies evaluating the diagnostic value of ¹⁸F-FDG-PET/CT for the detection of peripheral emboli and secondary infectious foci in patients with infective endocarditis and cardiac device infections.

RECENT FINDINGS

Detection of extracardiac septic localizations in patients with infective endocarditis and cardiac device infections is crucial, as it may impact the diagnosis, prognosis, and therapeutic management. Recent literature substantiated the clinical usefulness of ¹⁸F-FDG-PET/CT in this setting. ¹⁸F-FDG-PET/CT has proven its high diagnostic value for the detection of peripheral emboli in patients with infective endocarditis and cardiac device infections, substantially affecting patients' outcome and treatment. A multimodal approach, combining the high sensitivity of ¹⁸F-FDG-PET/CT with morphological imaging seems promising.

S. aureus endocarditis: Clinical aspects and experimental approaches

Infective endocarditis (IE) is a life-threatening disease, caused by septic vegetations and inflammatory foci on the surface of the endothelium and the valves. Due to its complex and often indecisive presentation the mortality rate is still about 30%. Most frequently bacterial microorganisms entering the bloodstream are the underlying origin of the intracardiac infection. While the disease was primarily restricted to younger patients suffering from rheumatic heart streptococci infections, new at risk categories for Staphylococcus (S.) aureus infections arose over the last years. Rising patient age, increasing drug resistance, intensive treatment conditions such as renal hemodialysis, immunosuppression and long term indwelling central venous catheters but also the application of modern cardiac device implants and valve prosthesis have led to emerging incidences of S. aureus IE in health care settings and community. The aetiologic change has impact on the pathophysiology of IE, the clinical presentation and the overall patient management. Despite intensive research on appropriate in vitro and in vivo models of IE and gained knowledge about the fundamental mechanisms in the formation of bacterial vegetations and extracardiac complications, improved understanding of relevant bacterial virulence factors and triggered host immune responses is required to help developing novel antipathogenic treatment strategies and pathogen specific diagnostic markers. In this review, we summarize and discuss the two main areas affected by the changing patient demographics and provide first, recent knowledge about the pathogenic strategies of S. aureus in the induction of IE, including available experimental models of IE used to study host-pathogen interactions and diagnostic and therapeutic targets. In a second focus we present diagnostic (imaging) regimens for patients with S. aureus IE according to current guidelines as well as treatment strategies and surgical recommendations.

[Complicated transcatheter aortic-valve endocarditis with abscess and pseudoaneurysm: Value of the ECG-gated multidetector computed tomography angiography]

A 80-year-old man was admitted to catheterization room for an acute infero-lateral ST-elevation myocardial infarction (STEMI). Coronary angiography showed a thrombotic occlusion of the second left marginal branch, and normal other coronary arteries. The thrombo-embolic mechanism of the STEMI, and the infectious context in this patient who had had a transcatheter aortic valve implantation (TAVI) two months earlier, led us to suspect a bioprosthesis endocarditis. It was confirmed by transthoracic and transoesophageal echocardiography, which showed an aortic-mitral curtain abscess and aortic bioprosthesis vegetations, associated to Enterococcus faecalis bacteriemia. In order to specify the diagnosis, an ECG-gated multidetector CT angiography (MDCTA) had been performed. Additionally to echocardiographic findings, MDCTA showed a pseudo-aneurysm, sized 20 to 22mm, beginning from the outflow tract of the left ventricle to end on the antero-lateral face of the aorta. The patient was referred for emergency aortic bioprosthesis removal and replacement. Through this case, MDCTA showed its importance for the diagnosis and the prognostic evaluation of cardiac prosthesis endocarditis. MDCTA provided additional informations that echocardiography could not detect, because of artifacts caused by the prosthetic material and calcifications, frequent in elderly patients with comorbidities.

Comparison of Outcome of Possible Versus Definite Infective Endocarditis Involving Native Heart Valves

There are very few data on the prognosis of possible versus definite infective endocarditis (IE). We studied data from 365 consecutive patients with IE involving native heart valve seen in an academic institution from 1990 to 2012. Patients were classified according to the modified Duke criteria for IE: patients with possible IE (n = 101, 28%) and those with definite IE (n = 264, 72%). Patients with possible IE were older than those with definite IE (66 ± 15 vs 62 ± 16, p = 0.05). A causative microorganism was identified in 66% of patients with possible IE versus all patients with definite IE (p <0.0001) and only 41% had major echocardiographic criteria (vs 100%; p <0.0001). Overall, 139 patients died over a mean ± SD follow-up of 3.9 ± 4.5 years (median 2.2, interquartile range 5.9 years). Patients with possible and definite IE had a similar risk of death. Independent predictors of long-term mortality were increasing age (hazard ratio [HR] 1.02, 95% confidence interval [CI] 1.01 to 1.04; p = 0.0009), vegetation length >15 mm (HR 1.87, 95% CI 1.14 to 3.06; p = 0.01), and stroke (HR 4.10, 95% CI 1.84 to 9.17; p = 0.0006), whereas infection of mitral valve (HR 0.57, 95% CI 0.34 to 0.94; p = 0.03) and surgery (HR 0.43, 95% CI 0.19 to 0.99; p = 0.05) were associated with a better prognosis. Patients with definite IE and those with possible IE who did not undergo surgery had a worse prognosis than their counterparts with surgery. In conclusion, unselected patients with possible IE (Duke criteria) had a similar prognosis than those with definite IE.

Infective Endocarditis: How Do We Currently Interpret the Duke Minor Criterion "Predisposing Heart Condition" in Native Valves?

INTRODUCTION

The term "predisposing heart condition" is used as an indication of antimicrobial prophylaxis to prevent infective endocarditis (IE) and as a criterion for diagnosing IE according to modified Duke criteria. The purpose of this survey was to elaborate clinician's knowledge and opinion on relevant heart conditions as a Duke minor criterion for the diagnosis of IE.

METHODS

A questionnaire was created that consisted of two knowledge and two opinion questions on the term predisposing heart condition. The survey included results from 318 questionnaires with responses from specialists in the field of internal medicine, infectious diseases, and cardiology.

RESULTS

The answers of what participants believed to be currently a Duke minor criterion and what they thought should be minor criterion were very distributed with a median accordance of 33%.

CONCLUSION

The survey indicates that there is significant uncertainty regarding what is encountered as a Duke minor criterion predisposing heart condition in a native valve.