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1,143 result(s) for "Prosthetic valve"
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Diagnostic Performance of Prosthetic Heart Valve Infective Endocarditis: A Comparison of Diagnostic Modalities and Proposed Algorithm
Prosthetic valve endocarditis (PVE) is a potentially life-threatening complication following valve replacement surgery, with an increasing incidence due to the rise in prosthetic valve procedures. Accurate and timely diagnosis of PVE remains challenging due to altered cardiac anatomy and imaging artifacts. Traditional diagnostic tools, such as Duke criteria, were originally developed for native valve endocarditis and demonstrate suboptimal sensitivity and specificity in the context of PVE. Recent advancements incorporated novel molecular and imaging modalities, such as polymerase chain reaction and nuclear imaging techniques, in an attempt to improve the diagnostic accuracy. However, no single modality currently serves as a definitive gold standard. In conclusion, in this review, we critically compare the diagnostic performance of available tools for PVE, analyzing their sensitivity, specificity, positive predictive value, and negative predictive value. We further propose a practice approach to facilitate early and accurate diagnosis, ultimately aiming to improve clinical outcomes in patients with suspected PVE.
Survival and Recurrence of Endocarditis following Mechanical vs. Biological Aortic Valve Replacement for Endocarditis in Patients Aged 40 to 65 Years: Data from the INFECT-Registry
Background: Infective endocarditis (IE) is a serious disease, and in many cases, surgery is necessary. Whether the type of prosthesis implanted for aortic valve replacement (AVR) for IE impacts patient survival is a matter of debate. The aim of the present study is to quantify differences in long-term survival and recurrence of endocarditis AVR for IE according to prosthesis type among patients aged 40 to 65 years. Methods: This was an analysis of the INFECT-REGISTRY. Trends in proportion to the use of mechanical prostheses versus biological ones over time were tested by applying the sieve bootstrapped t-test. Confounders were adjusted using the optimal full-matching propensity score. The difference in overall survival was compared using the Cox model, whereas the differences in recurrence of endocarditis were evaluated using the Gray test. Results: Overall, 4365 patients were diagnosed and operated on for IE from 2000 to 2021. Of these, 549, aged between 40 and 65 years, underwent AVR. A total of 268 (48.8%) received mechanical prostheses, and 281 (51.2%) received biological ones. A significant trend in the reduction of implantation of mechanical vs. biological prostheses was observed during the study period (p < 0.0001). Long-term survival was significantly higher among patients receiving a mechanical prosthesis than those receiving a biological prosthesis (hazard ratio [HR] 0.546, 95% CI: 0.322–0.926, p = 0.025). Mechanical prostheses were associated with significantly less recurrent endocarditis after AVR than biological prostheses (HR 0.268, 95%CI: 0.077–0.933, p = 0.039). Conclusions: The present analysis of the INFECT-REGISTRY shows increased survival and reduced recurrence of endocarditis after a mechanical aortic valve prosthesis implant for IE in middle-aged patients.
Prosthetic Valve Endocarditis Caused by Pasteurella dagmatis , Germany
An 81-year-old male patient in Germany had prosthetic valve endocarditis caused by Pasteurella dagmatis after a domestic cat bite. We surgically treated a paravalvular abscess and administered definitive antibiotic therapy consisting of penicillin G and levofloxacin. The patient was discharged from the intensive care unit in good condition 21 days after the surgery.
Prosthetic Heart Valves Thrombosis with Infectious Endocarditis - A Practical Review
Simultaneous or sequential combination of prosthetic valve (PV) thrombosis and infectious endocarditis is a rare clinical finding. The management of these patients involves a complex multidisciplinary strategy using clinical judgment and imaging techniques. Transesophageal echocardiography (TEE) and especially 3D transesophageal echocardiography is essential. Moreover, positron emission tomography with fluorodeoxyglucose (F18-FDG PET/CT) can be a valuable tool to diagnose and manage these complicated clinical scenarios.We present the case of a 65-year-old patient who was admitted in our clinic for paroxysmal nocturnal dyspnea and chills for one week. He had multiple surgical interventions for rheumatic mitral valve disease (percutaneous mitral valvuloplasty in 2008, and mitral valve replacement and tricuspid annuloplasty in October 2019).At admission, the diagnosis of prosthetic valve thrombosis was established taking into account the clinical context (low INR values for the last two months), the patient symptoms and the echocardiographic findings. IV unfractionated heparin was administered. One week after admission the patient’s clinical status further deteriorated. TEE reevaluation showed partial thrombus regression with elements suggestive for concomitant infectious endocarditis. The diagnosis key is the clinical evolution and repeated TEE evaluations. In our case, they enabled the probable diagnosis of a sequential association of thrombosis and infectious endocarditis on mechanical PV. The therapeutic approach requires a high clinical suspicion and a prompt management, emergent surgery being the only lifesaving strategy in unstable patients with obstructive mechanical pathology.
Easy surgical explantation technique for self-expanding transcatheter aortic valve: ‘lasso technique’
A prosthesis with a self-expanding nitinol frame firmly incorporates into the aortic wall and thus is difficult to explant. We introduce a novel technique that simplifies explantation.
The role of multimodal imaging in the diagnosis of prosthetic valve and intracardiac device endocarditis: A review
Infective endocarditis (IE) is a severe cardiac condition associated with substantial morbidity and mortality. Traditionally, the modified Duke’s criteria have been used to establish the diagnosis of IE, which includes using transthoracic and transesophageal echocardiography. While echocardiography performs well in diagnosing native valve endocarditis, its diagnostic accuracy decreases in patients with prosthetic valves or implanted cardiac devices such as pacemakers and defibrillators. Given these limitations and advancements in cardiac imaging, including multimodal computed tomography, magnetic resonance imaging, and positron emission tomography, there has been growing interest in the utility of these techniques for diagnosing prosthetic valve endocarditis (PVE) and Cardiovascular implantable electronic device infection (CIEDI). Although numerous studies have investigated the value of these imaging modalities, their findings have been inconsistent. This article aims to reevaluate the role of advanced imaging in diagnosing PVE and CIEDI and its impact on managing prosthetic valves and device-related infective endocarditis. Methods A comprehensive literature search was conducted in PubMed, Cochrane library, Google Scholar, Embase, and other relevant databases. Key terms such as ‘infective endocarditis,’ ‘multimodal imaging,’ ‘prosthetic valve endocarditis,’ ‘18F-FDG PET,’ ‘cardiac MRI,’ and ‘cardiac CT’ were used to identify studies that investigated the role of these imaging modalities in diagnosing PVE and CIEDI. Publications with full text including randomized controlled trials, retrospective studies, case reports, case series, reviews of literature, and society guidelines were included.
Easy surgical explantation technique for sutureless Perceval S prosthesis, ‘lasso technique’: a case report
Background Due to structural valve deterioration of sutureless aortic prosthesis, there is a need for explantation of the prothesis. We introduce a surgical technique to explant sutureless aortic prosthesis, which has a self-expanding stent incorporated into the aortic wall. Case presentation An 82-year-old man who had undergone sutureless aortic valve replacement 6 years previously underwent redo-aortic and mitral valve replacement because of severe prosthetic aortic valve stenosis and mitral regurgitation. The sutureless prosthesis was explanted using ‘lasso technique’. The patient was discharged after 7 days without complications. Conclusions We presented a useful technique to explant a sutureless aortic prosthesis.
Rise of the new generation of mechanical heart valve prostheses: An in-depth in vitro study
Valvular heart disease, particularly aortic valve (AV) calcification, remains a significant issue, with AV replacement surgeries among the most common procedures. Current surgical options include mechanical heart valves (MHVs) and bioprosthetic valves, each with inherent limitations. MHVs offer long-term durability but require lifelong anticoagulation therapy, while bioprosthetic valves provide superior hemodynamics but lack durability. The MHV’s non-physiological flow patterns through the hinges and spikes in regional backflow velocity (RBV) during closure may contribute to the need for anticoagulation. This study evaluates two emerging MHVs, the iValve and Triflo, alongside established prosthetic valves. The iValve, featuring a novel bileaflet design, and the Triflo, a trileaflet valve, aim to overcome current MHV limitations. In vitro testing used a pulse duplicator system to assess projected open area (POA), volumetric flow rate, regurgitant volumes, and trans-AV pressure relative to mean pressure (pressure ratio). POA and volumetric flow rates were used to calculate flow velocity and RBV. Results indicate that the iValve and Triflo achieved comparable pressure ratios and significantly lower mean and peak RBV values than traditional MHVs like the SJM and On-X. This suggests improved flow dynamics and reduced shear stress on blood components, potentially minimizing anticoagulation requirements. The iValve prototypes showed regurgitant volumes comparable to conventional MHVs, while the Triflo performed similarly to the control valve. These findings underscore the potential of next-generation MHVs to combine durability, hemodynamic performance, and reduced thrombogenic risk closer to the native valve.
Can mechanical heart valves perform similarly to tissue valves? An in vitro study
Current surgical aortic valve (AV) replacement options include bioprosthetic and mechanical heart valves (MHVs), each with inherent limitations. Bioprosthetic valves offer superior hemodynamics but suffer from durability issues, typically initiating deterioration within 7–8 years. MHVs, while durable, necessitate lifelong anticoagulation therapy, presenting risks such as severe bleeding and thromboembolic events. The need for anticoagulants is caused by non-physiological flow through the hinge area during the closed phase and large spikes of regional backflow velocity (RBV) during the closing phase that produces high shear events. This study introduces the iValve, a novel MHV designed to combine the hemodynamic benefits of bioprosthetic valves with the durability of MHVs without requiring anticoagulation. The iValve features eye-like leaflets, a saddle-shaped housing, and an optimized hinge design to enhance blood flow and minimize thrombotic risk. Fabricated using 6061-T6 aluminum and polyether ether ketone (PEEK), twelve iValve iterations were evaluated for their opening and closing dynamics. The reported top-performing prototypes demonstrated competitive performance against industry standards. The proposed iValve prototype exhibited a mean RBV of −4.34 m/s with no spikes in RBV, performing similarly to bioprosthetic valves and significantly outperforming existing MHVs. The iValve’s optimized design showed a 7–10% reduction in closing time and a substantial decrease in RBV spikes, potentially reducing the need for anticoagulation therapy. This study highlights the iValve’s potential to revolutionize prosthetic heart valve technology by offering a durable, hemodynamically superior solution that mitigates the drawbacks of current MHVs.
Histological Findings in Infective Endocarditis—A Retrospective Cohort Study Conducted at “Dr. Carol Davila” Central Military Emergency University Hospital in Bucharest
Background: Histological findings of infective endocarditis (IEs) in mechanical valves present a complex diagnostic challenge owing to the lack of a precise definition. This ambiguity is further complicated by the natural degenerative processes that occur in the mechanical valves over time. Consequently, pathologists and clinicians face significant difficulties in distinguishing between genuine infective processes and the normal wear and tear of mechanical valves. Method: This retrospective cohort study was conducted between January 2017 and January 2024 and examined tissue samples from 93 patients who underwent a surgical removal of mechanical heart valves, with 41 cases suspected of infective endocarditis and 52 cases of non-IE. The researchers aimed to establish more precise histological criteria for distinguishing between these two conditions, focusing on two key features: vegetations and inflammatory patterns. Results: IE in patients with prosthetic heart valves presents distinct histological features that aid in the diagnosis and differentiation of non-infective complications. Hallmark characteristics include vegetation and inflammatory infiltrates with neutrophils. Valve tissue specimens from patients whose mechanical valves were removed because of non-infectious complications showed a different histological profile. Inflammatory infiltrates were observed in approximately 26% of these cases; however, they were primarily composed of macrophages and lymphocytes rather than neutrophils. Conclusions: By emphasizing neutrophil-rich inflammation as a key indicator, clinicians and pathologists could more effectively distinguish between true infective endocarditis and non-IE that can occur in the mechanical valves. This distinction is crucial for appropriate patient management as the treatment strategies for infective and non-infective valve conditions differ significantly.