Prosthetic Heart Valve Endocarditis Research Articles

Transcatheter Aortic Valve Implantation: The Evolving Role of the Radiologist in 2021.

Transcatheter aortic valve implantation (TAVI) has gained worldwide acceptance and implementation as an alternative therapeutic option in patients with severe aortic valve stenosis unable to safely undergo surgical aortic valve replacement. This transformative technique places the radiologist in a key position in the pre-procedural assessment of potential candidates for this technique, delivering key anatomical information necessary for patient eligibility and procedural safety. Recent trials also provide encouraging results to potentially extend the indication to patients with safer risk profiles. The review is based on a PubMed literature search using the search terms "transcatheter heart valve", "TAVI", "TAVR", "CT", "imaging", "MR" over a period from 2010-2020, combined with personal comments based on the author's experience. CT plays a prominent role in the pre-procedural workup, delivering as a true 3D imaging modality optimal visualization of the complex anatomy of the aortic root with simultaneous evaluation of the patency of the different access routes. As such, the contribution of CT is key for the determination of patient eligibility and procedural safety. This input is supplementary to the contributions of other imaging modalities and forms an important element in the discussions of the Heart Valve Team. Knowledge of the procedure and its characteristics is necessary in order to provide a comprehensive and complete report. While the role of CT in the pre-procedural evaluation is well established, the contribution of CT and MR and the clinical significance of their findings in the routine follow-up after the intervention are less clear and currently the subject of intense investigation. Important issues remain, including the occurrence and significance of subclinical leaflet thrombosis, prosthetic heart valve endocarditis, and long-term structural valve degeneration. · CT plays a crucial role in evaluating transcatheter heart valve candidates. · Evaluation must include the dimensions of the aortic root and access paths. · The exact post-procedural role of CT and MRI has not yet been determined.. · Salgado R, El Addouli H, Budde RP. Transcatheter Aortic Valve Implantation: The Evolving Role of the Radiologist in 2021. Fortschr Röntgenstr 2021; 193: 1411 - 1425.

Imaging Spectrum of Valvular and Paravalvular Complications of Prosthetic Heart Valve at CT Angiography.

Prosthetic heart valve (PHV) dysfunction is an uncommon but potentially life-threatening condition. In routine practice, transthoracic echocardiography and cinefluoroscopy comprise first-line imaging for the diagnostic evaluation of PHV dysfunction. In cases in which the findings of echocardiography and cinefluoroscopy remain inconclusive or are contradictory, CT angiography can resolve these conflicts. CT angiography also provides incremental diagnostic information about patients with suspected PHV obstruction and endocarditis, in which case it can demonstrate the anatomic substrate and extent of involvement. Additionally, information regarding the coronary arteries, cardiac dimensions, and retrosternal space may be obtained in cases in which repeat surgery is planned. This imaging essay describes the imaging spectrum of valvular and paravalvular complications of PHV at CT angiography and how the knowledge regarding the spectrum of complications can be incorporated into multimodality imaging for guiding clinical management. Keywords: Prosthetic Heart Valve Dysfunction, Prosthetic Heart Valve Thrombosis, Pannus, Paravalvular Leak, CT Angiography, Cardiac, Valves Supplemental material is available for this article. © RSNA, 2021.

RETRACTED: Real time monitoring of medical images and nursing intervention after heart valve replacement

Heart valve surgery is a leak reduction or repair operation or replacement of the infected valve. To alleviate the symptoms of valvular heart disease, it can prevent permanent damage to the heart. Heart valve surgery is normally open-heart surgery. This means cutting the sternum and to reach the heart. However, in response to the problems and other factors, there may be a procedure of other alternatives. Echocardiography and fluoroscopy is the main technique used for evaluation of the Prosthetic Heart Valve (PHV), for a particular cause restriction, they are the degree of morphological substrate or PHV pathology it cannot identify. Cardiac computed tomography or magnetic resonance imaging has become the new imaging modalities for the valve prosthesis. It propose the possibility of a systematic literature review based on all of the experiments and the patient's study. Pitfalls of Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) provide an overview of the evaluation of the PHV. Metal artifacts might interfere with prosthetics analyzed directly in the MRI, provides information about the flow pattern and velocity associated with PHV. MRI shows an abnormal, asymmetric flow pattern of PHV barriers, enables the evaluation of repair reflux. Therefore, it offers great clinical relevance as a complementary imaging tool for diagnosing CT suspected PHV disorders and endocarditis. MRI is more research to enable a normal identification from pathological conditions required to provide a diagnostic reference value, to be used for functional PHV evaluation potential shows.

Too much or not enough; balancing insulin levels in a diabetic patient sent for 18F-FDG PET/CT of prosthetic heart valve endocarditis

Too much or not enough; balancing insulin levels in a diabetic patient sent for 18F-FDG PET/CT of prosthetic heart valve endocarditis

P3663Prevalence of infective endocarditis in patients with a left-sided heart valve prosthesis: a nationwide study

Abstract Background Increasing attention has been given to patients with blood stream infection (BSI) and the concurrent prevalence of infective endocarditis (IE). However, there exist a gap in knowledge on the prevalence of IE among patients with a left-sided heart valve prosthesis and BSI. Purpose To examine the prevalence between different BSI and IE in patients with a left-sided heart valve prosthesis. Methods By linking Danish nationwide registries, we were able to identify patients with a left-sided prosthetic heart valve and first-time BSI of interest (Enterococcus faecalis, Staphylococcsus aureus, streptococci species (spp.), and coagulase negative staphylococci [CoNS]) in the period of 2010–2016. Concurrent admission for IE was identified from the Danish National Patient Registry in a period of up to 14 days after the BSI. Results A total of 1,465 patients with BSI were included (1,319 patients with an aortic valve prosthesis [82.6% bioprosthetic] and 146 patients with a mitral valve prosthesis [48.6% bioprosthetic]). Among the included patients, 244 had E. faecalis (median age: 78.3 years, 77.0% male), 301 had S. aureus (median age: 76.9 years, 69.1% male), 401 had streptococci spp. (median age: 78.0 years, 69.1% male) and 519 had CoNS (median age: 76.4 years, 64.2% male). The percentage of patients with a diagnosis of IE in relation to the BSI was 44.3%, 33.6%, 34.4%, and 7.9% for E. faecalis, S. aureus, streptococci spp., and CoNS, respectively. No difference in the overall results was seen by type of valve prosthesis, sex, or age group. Percentage of patients with endocarditis Conclusion In patients with a left-sided heart valve prosthesis, IE was diagnosed in almost half of the patients with E. faecalis, in 1/3 with S. aureus or streptococci spp. and in 1 in 12 with CoNS BSI. Future studies may try to explain why some microbes are more likely to cause prosthetic heart valve endocarditis, than others are.

Standardized uptake values in FDG PET/CT for prosthetic heart valve endocarditis: a call for standardization

BackgroundThe significance of and threshold values for the standardized uptake value (SUV) in FDG PET/CT to diagnose prosthetic heart valve (PHV) endocarditis (PVE) are unclear at present. MethodsA literature search was performed in the PubMed and EMBASE medical databases, comprising the following terms: (FDG OR *fluorode* OR *fluoro-de*) AND (endocarditis OR prosthetic heart valve OR valve replacement). Studies reporting SUVs correlated to the diagnosis of PVE were selected for analysis. Results8 studies were included, with a total of 330 PHVs assessed. SUVs for PVE varied substantially across studies due to differences in acquisition, reconstruction, and measurement protocols, with median SUVmax values for rejected PVE ranging from 0.5 to 4.9 and for definite PVE ranging from 4.2 to 7.4. ConclusionReported SUV values for PVE are not interchangeable between sites, and further standardization of quantification is desirable. To this end, optimal protocols for patient preparation, image acquisition, and reconstruction and measurement methods need to be standardized across centers.

Dual-time-point FDG PET/CT imaging in prosthetic heart valve endocarditis

PurposeFDG PET/CT has been of increasing interest in the diagnostic workup of prosthetic heart valve endocarditis (PVE). Some reports advocate later imaging time points to improve the diagnostic accuracy for PVE. In this study, we compared standard and late FDG PET/CT images in patients with a clinical suspicion of PVE. Materials and MethodsFourteen scans in 13 patients referred for FDG PET/CT for suspicion of PVE performed at standard (60 min post injection) and late (150 min post injection) time points were scored based on visual interpretation and semi-quantitatively with SUVmax and target-to-background ratio (TBR, defined as [SUVmax valve/SUVmean blood pool]). Final diagnosis was based on surgical findings in all cases of infection (n = 6) and unremarkable follow-up in all others (n = 8). ResultsLate images were more prone to false positive interpretation for both visual and semi-quantitative analyses. Visual analysis of the standard images yielded 1 false negative and 1 false positive result. On the late images, no scans were false negative but 5 scans were false positive. ConclusionLate FDG PET/CT imaging for PVE seems prone to false positive results. Therefore, late imaging should be interpreted with caution.

Improving the Diagnostic Performance of 18F-Fluorodeoxyglucose Positron-Emission Tomography/Computed Tomography in Prosthetic Heart Valve Endocarditis.

18F-Fluorodeoxyglucose (FDG) positron-emission tomography/computed tomography (PET/CT) was recently introduced as a new tool for the diagnosis of prosthetic heart valve endocarditis (PVE). Previous studies reporting a modest diagnostic accuracy may have been hampered by unstandardized image acquisition and assessment, and several confounders, as well. The aim of this study was to improve the diagnostic performance of FDG PET/CT in patients in whom PVE was suspected by identifying and excluding possible confounders, using both visual and standardized quantitative assessments. In this multicenter study, 160 patients with a prosthetic heart valve (median age, 62 years [43-73]; 68% male; 82 mechanical valves; 62 biological; 9 transcatheter aortic valve replacements; 7 other) who underwent FDG PET/CT for suspicion of PVE, and 77 patients with a PV (median age, 73 years [65-77]; 71% male; 26 mechanical valves; 45 biological; 6 transcatheter aortic valve replacements) who underwent FDG PET/CT for other indications (negative control group), were retrospectively included. Their scans were reassessed by 2 independent observers blinded to all clinical data, both visually and quantitatively on available European Association of Nuclear Medicine Research Ltd-standardized reconstructions. Confounders were identified by use of a logistic regression model and subsequently excluded. Visual assessment of FDG PET/CT had a sensitivity/specificity/positive predictive value/negative predictive value for PVE of 74%/91%/89%/78%, respectively. Low inflammatory activity (C-reactive protein <40 mg/L) at the time of imaging and use of surgical adhesives during prosthetic heart valve implantation were significant confounders, whereas recent valve implantation was not. After the exclusion of patients with significant confounders, diagnostic performance values of the visual assessment increased to 91%/95%/95%/91%. As a semiquantitative measure of FDG uptake, a European Association of Nuclear Medicine Research Ltd-standardized uptake value ratio of ≥2.0 was a 100% sensitive and 91% specific predictor of PVE. Both visual and quantitative assessments of FDG PET/CT have a high diagnostic accuracy in patients in whom PVE is suspected. FDG PET/CT should be implemented early in the diagnostic workup to prevent the negative confounding effects of low inflammatory activity (eg, attributable to prolonged antibiotic therapy). Recent valve implantation was not a significant predictor of false-positive interpretations, but surgical adhesives used during implantation were.

18F-fluorodeoxyglucose positron emission/computed tomography and computed tomography angiography in prosthetic heart valve endocarditis: from guidelines to clinical practice.

The timely diagnosis of prosthetic heart valve endocarditis remains challenging yet of utmost importance. 18F-fluorodeoxyglucose (18 F-FDG) positron emission/computed tomography (PET/CT) and cardiac computed tomography angiography (CTA) were recently introduced as additional diagnostic tools in the most recent ESC guidelines on infective endocarditis. However, how to interpret PET/CT findings with regard to what is to be considered abnormal, what the potential confounders may be, as well as which patients benefit most from these additional imaging techniques and how to best perform them in these often-complex patients, remains unclear. This review focusses on factors regarding patient selection and image acquisition that need to be taken into account when employing 18F-FDG PET/CT and CTA in daily clinical practice, and the importance of a multidisciplinary Endocarditis Team herein. Furthermore, it emphasizes the need for standardized acquisition protocols and image interpretation, especially now that these techniques are starting to be widely embraced by the cardiovascular society.

Non-Invasive Imaging of Prosthetic Heart Valves with a Focus on Endocarditis

Prosthetic heart valve (PHV) implantation can be a life-saving intervention. However, it does provide the patient with a lifelong chronic condition. Prosthetic heart valves can become dysfunctional due to various causes. The most dreaded complication is PHV endocarditis. Patients with a PHV are at higher risk to develop endocarditis because of the exposure of foreign material to the bloodstream. The reported incidence of PHV endocarditis varies considerably in the literature [1], probably because PHV endocarditis is such a difficult diagnosis to establish. The patient can present with a variety of symptoms that are often non-specific. Diagnosis of endocarditis has relied on the Duke criteria, which incorporates findings from echocardiography, physical examination, and blood cultures. The Duke criteria are known to be less accurate in PHV endocarditis [1]. Echocardiography is often hampered by PHV-induced artifacts, and blood cultures are more often negative.

Novel imaging strategies for the detection of prosthetic heart valve obstruction and endocarditis.

Prosthetic heart valve (PHV) dysfunction remains difficult to recognise correctly by two-dimensional (2D) transthoracic and transoesophageal echocardiography (TTE/TEE). ECG-triggered multidetector-row computed tomography (MDCT), 18-fluorine-fluorodesoxyglucose positron emission tomography including low-dose CT (FDG-PET) and three-dimensional transoesophageal echocardiography (3D-TEE) may have additional value. This paper reviews the role of these novel imaging tools in the field of PHV obstruction and endocarditis.For acquired PHV obstruction, MDCT is of additional value in mechanical PHVs to differentiate pannus from thrombus as well as to dynamically study leaflet motion and opening/closing angles. For biological PHV obstruction, additional imaging is not beneficial as it does not change patient management. When performed on top of 2D-TTE/TEE, MDCT has additional value for the detection of both vegetations and pseudoaneurysms/abscesses in PHV endocarditis. FDG-PET has no complementary value for the detection of vegetations; however, it appears more sensitive in the early detection of pseudoaneurysms/abscesses. Furthermore, FDG-PET enables the detection of metastatic and primary extra-cardiac infections. Evidence for the additional value of 3D-TEE is scarce.As clinical implications are major, clinicians should have a low threshold to perform additional MDCT in acquired mechanical PHV obstruction. For suspected PHV endocarditis, both FDG-PET and MDCT have complementary value.

Multimodality Imaging Assessment of Prosthetic Heart Valves.

Echocardiography and fluoroscopy are the main techniques for prosthetic heart valve (PHV) evaluation, but because of specific limitations they may not identify the morphological substrate or the extent of PHV pathology. Cardiac computed tomography (CT) and magnetic resonance imaging (MRI) have emerged as new potential imaging modalities for valve prostheses. We present an overview of the possibilities and pitfalls of CT and MRI for PHV assessment based on a systematic literature review of all experimental and patient studies. For this, a comprehensive systematic search was performed in PubMed and Embase on March 24, 2015, containing CT/MRI and PHV synonyms. Our final selection yielded 82 articles on surgical valves. CT allowed adequate assessment of most modern PHVs and complemented echocardiography in detecting the obstruction cause (pannus or thrombus), bioprosthesis calcifications, and endocarditis extent (valve dehiscence and pseudoaneurysms). No clear advantage over echocardiography was found for the detection of vegetations or periprosthetic regurgitation. Whereas MRI metal artifacts may preclude direct prosthesis analysis, MRI provided information on PHV-related flow patterns and velocities. MRI demonstrated abnormal asymmetrical flow patterns in PHV obstruction and allowed prosthetic regurgitation assessment. Hence, CT shows great clinical relevance as a complementary imaging tool for the diagnostic work-up of patients with suspected PHV obstruction and endocarditis. MRI shows potential for functional PHV assessment although more studies are required to provide diagnostic reference values to allow discrimination of normal from pathological conditions.

Are novel non-invasive imaging techniques needed in patients with suspected prosthetic heart valve endocarditis? A systematic review and meta-analysis.

ObjectivesMultimodal non-invasive imaging plays a key role in establishing a diagnosis of PHV endocarditis. The objective of this study was to provide a systematic review of the literature and meta-analysis of the diagnostic accuracy of TTE, TEE, and MDCT in patients with (suspected) PHV endocarditis.MethodsStudies published between 1985 and 2013 were identified via search and cross-reference of PubMed/Embase databases. Studies were included if (1) they reported on the non-invasive index tests TTE, TEE, or MDCT; (2) data was provided on PHV endocarditis as the condition of interest; and (3) imaging results were verified against either surgical inspection/autopsy or clinical follow-up reference standards, thereby enabling the extraction of 2-by-2 tables.ResultsTwenty articles (including 496 patients) met the inclusion criteria for PHV endocarditis. TTE, TEE, and MDCT + TEE had a pooled sensitivity/specificity for vegetations of 29/100 %; 82/95 %, and 88/94 %, respectively. The pooled sensitivity/specificity of TTE, TEE, and MDCT + TEE for periannular complications was 36/93 %, 86/98 %, and 100/94 %, respectively.ConclusionsTEE showed good sensitivity and specificity for establishing a diagnosis of PHV endocarditis. Although MDCT data are limited, this review showed that MDCT in addition to TEE may improve sensitivity in detecting life-threatening periannular complications.Key Points• Multimodal imaging is an important ingredient of diagnostic workup for PHV endocarditis.• Transthoracic and transesophageal echography may miss life-threatening periannular complications.• MDCT can improve sensitivity for the detection of life-threatening periannular complications.Electronic supplementary materialThe online version of this article (doi:10.1007/s00330-015-3605-7) contains supplementary material, which is available to authorized users.

Cardiac computed tomography angiography results in diagnostic and therapeutic change in prosthetic heart valve endocarditis

Echocardiography may miss prosthetic heart valve (PHV) endocarditis which advocates for novel imaging techniques to improve diagnostic accuracy and patient outcome. The purpose of this study was to determine the complementary diagnostic value of cardiac computed tomography angiography (CTA) to the clinical routine workup including transthoracic and transesophageal echocardiography (TTE/TEE) in patients with suspected PHV endocarditis and its impact on patient treatment. A diagnostic prospective cross-sectional study was chosen as design. Besides clinical routine workup (including TTE/TEE), CTA was performed to assess its diagnostic accuracy and complementary diagnostic/therapeutic value. For the diagnostic accuracy, the reference standard was surgical findings or clinical follow-up. To determine the complementary diagnostic/therapeutic value an expert-panel was used as reference standard. Twenty-eight patients were included. CTA resulted in a major diagnostic change in six patients (21 %) mainly driven by novel detection of mycotic aneurysms by CTA. Furthermore, treatment changes occurred in seven patients (25 %) compared to clinical routine workup. Diagnostic accuracy of routine clinical workup plus CTA was superior to clinical routine workup alone for the detection of PHV endocarditis in general, vegetations and peri-annular extension. This study demonstrates that CTA and clinical workup including TTE and TEE are complementary in patients with PHV endocarditis. Therefore, CTA imaging has to be considered after clinical routine workup in patients with a high suspicion on PHV endocarditis.

Fusion of cardiac computed tomography angiography and 18F-fluorodesoxyglucose positron emission tomography for the detection of complicated prosthetic heart valve endocarditis

Purpose: PHV endocarditis is complicated by peri-annular extension (abscesses/mycotic aneurysms) in 50% of patients and has an in-hospital mortality of 30%. Transthoracic and Transesophageal Echocardiography (TTE and TEE) may fail to recognize peri-annular extensions, although this is an indication for urgent surgery. Therefore Computed Tomography Angiography (CTA) fused with 18F-Fluorodesoxyglucose Positron Emission Tomography (FDG-PET) may be of additional value. Methods: PHV patients that underwent FDG-PET were selected from the hospital database. CTA images were fused with FDG-PET images and the Standardized Uptake Value (SUV) ratio was measured. Imaging findings were compared to the reference standard: surgical inspection. Results: Eleven PHV endocarditis cases and four normal functioning PHV controls were identified. All cases and controls underwent TTE, TEE and CTA. In 11/11 (100%) endocarditis cases, imaging by fused FDG-PET and CTA detected high FDG uptake around the PHV. Surgical inspection confirmed peri-annular extension of endocarditis in all cases. Controls (n=4) were all free of significant FDG uptake. SUV ratios around the PHV ring were significantly (p=0.001) higher in endocarditis cases; 4.6 (IQR 3.8-5.1) compared to controls; 2.0 (IQR 1.7-2.1). SUV ratios around the PHV ring in cases were all above 2.6, whereas all controls had SUV ratio's below 2.3. ![Figure][1] A:TEE, B:CTA, C:Fused CTA and FDG-PET Conclusion: Fused cardiac FDG-PET and CTA imaging is a promising tool to correctly diagnose PHV endocarditis. SUV ratios may be used to discriminate PHV endocarditis with peri-annular extension from non-infected PHVs or PHVs endocarditis without peri-annular extension. Fused FDG-PET and CTA may be considered in patients with a high suspicion of PHV endocarditis but inconclusive routine work-up. [1]: pending:yes

Indirect Immunofluorescence as a Diagnostic Tool in a Prosthetic Heart Valve Endocarditis due to Actinobacillus actinomycetemcomitans and Staphylococcus epidermidis

A late prosthetic valve endocarditis due to Actinobacillus actinomycetemcomitans and Staphylococcus epidermidis in a 72-year-old man is reported. A simple indirect immunofluorescence technique was used to confirm the etiological diagnosis. This test may be useful when diagnostic problems occur in infections with microorganisms of uncertain pathogenic importance.

Increased Antimicrobial Resistance of Pathogenic Coagulase-Negative Staphylococci From Blood Cultures (1961–1981)

Coagulase-negative staphylococci (CONS) have only recently gained notoriety as pathogens. Several reports have established their pathogenicity in bacterial endocarditis, prosthetic heart valve endocarditis, intraventricular shunts for treatment of hydrocephalus and intravenous catheters. One difficult decision for physicians is determining whether a particular CONS isolate is pathogenic or contaminant. The differentiation of pathogenic and contaminant CONS has recently been noted, but further studies are needed to aid in this differentiation. Data on antimicrobial susceptibilities of positive blood culture isolates were recently compiled at this institution. This report compares antimicrobial susceptibilities of pathogenic and contaminant CONS and Staphylococcus aureus blood culture isolates from 1961-1981 at this institution.

Penicillium endocarditis following open heart surgery and prosthetic valve insertion

Two instances of postoperative prosthetic heart valve endocarditis caused by a Penicillium species occurred in a man and in a woman after replacement of aortic and aortic and mitral valves, respectively. Prosthetic cardiac valve fungal endocarditis has been reported in 33 patients prior to the present report; in all but four instances infection was caused by a Candida species or by an Aspergillus species. All reported patients with adequately documented prosthetic valve fungal endocarditis have died. An inordinately high incidence of males is noted among patients with fungal prosthetic heart valve infection. The basis for the apparently enhanced susceptibility of males to such infection remains to be clarified.