Early Prosthetic Valve Endocarditis with Mycobacterium Tuberculosis after Mitral Valve Replacement: A Case Report

Background: Tuberculous endocarditis is a rare but serious complication of heart valve replacement surgery. We report the case of a 24-year-old patient, who presented with tuberculous endocarditis after mechanical mitral valve replacement, with a favorable clinical course following anti-tuberculosis treatment. Case Presentation: We report a 24-year-old male patient, admitted to the cardiac surgery department of the Fann Hospital (Dakar, Senegal), for the management of severe mixed (rheumatic and endocarditic) mitral insufficiency with associated tricuspid insufficiency. He had a history of recurrent angina and polyarthralgia in childhood, was hospitalized several times for refractory global cardiac decompensation, and for a suspected infective endocarditis a month before his admission. On admission, the clinical examination revealed signs suggestive of mitral and tricuspid insufficiency. Transthoracic echocardiography revealed severe post-endocarditic mitral insufficiency with A3 amputation, highly mobile 15 mm vegetations on the free edge of the large valve, moderate tricuspid insufficiency, and severe pulmonary artery hypertension. Mechanical mitral valve replacement and tricuspid valve annuloplasty using autologous pericardial strip were performed via median sternotomy. After ten days, the patient presented with global cardiac decompensation associated with a clinico-biological infectious syndrome, and tans-oesophageal echography revealed an abscess at the sinotubular junction, communicating with the aorta. A thoraco-abdomino-pelvic CT scan was done, which revealed a bilateral alveolar-interstitial syndrome with mediastinal lymphadenopathy. Anti-tuberculosis treatment with RHZE was initiated for 06 months. The clinical course was favorable. Conclusion: Tuberculous endocarditis in prostheses is a serious complication of heart valve replacement surgery, which may evolve favorably under medical treatment.

Multimodality imaging in the diagnosis and management of prosthetic valve endocarditis:A contemporary narrative review

Infective endocarditis is one of the leading life-threatening infections around the world.With the exponential growth in the field of transcatheter interventions and advances in specialized surgical techniques,the number of prosthetic valves and cardiac implantable devices has significantly increased.This has led to a steep rise in the number of cases of prosthetic valve endocarditis(PVE)comprising up to 30%of all cases.Clinical guidelines rely on the use of the modified Duke criteria;however,the diagnostic sensitivity of the modified Duke criteria is reduced in the context of PVE.This is in part attributed to prosthesis related artifact which greatly affects the ability of echocardiography to detect early infective changes related to PVE in certain cases.There has been increasing recognition of the roles of complementary imaging modalities and updates in international society recommendations.Prompt diagnosis and treatment can prevent the devastating consequences of this condition.Imaging modalities such as cardiac computed tomography and 18-fluorodeoxyglucose positron emission tomography/computed tomography are diagnostic tools that provide a complementary role to echocardiography in aiding diagnosis,pre-operative planning,and treatment decisionmaking process in these challenging cases.Understanding the strengths and limitations of these adjuvant imaging modalities is crucial for the implementation of appropriate imaging modalities in clinical practice.

Role of radionuclide imaging for diagnosis of device and prosthetic valve infections

Cardiovascular implantable electronic device(CIED) infection and prosthetic valve endocarditis(PVE) remain a diagnostic challenge.Cardiac imaging plays an important role in the diagnosis and management of patients with CIED infection or PVE.Over the past few years,cardiac radionuclide imaging has gained a key role in the diagnosis of these patients,and in assessing the need for surgery,mainly in the most difficult cases.Both ^(18)F-fluorodeoxyglucose positron emission tomography/computed tomography(^(18)F-FDG PET/CT) and radiolabelled white blood cell single-photon emission computed tomography/computed tomography(WBC SPECT/CT) have been studied in these situations.In their 2015 guidelines for the management of infective endocarditis,the European Society of Cardiology incorporated cardiac nuclear imaging as part of their diagnostic algorithm for PVE,but not CIED infection since the data were judged insufficient at the moment.This article reviews the actual knowledge and recent studies on the use of ^(18)F-FDG PET/CT and WBC SPECT/CT in the context of CIED infection and PVE,and describes the technical aspects of cardiac radionuclide imaging.It also discusses their accepted and potential indications for the diagnosis and management of CIED infection and PVE,the limitations of these tests,and potential areas of future research.

Effectiveness of Multidetector Computed Tomography in Prosthetic Valve Endocarditis

Background: Redo aortic valve replacement for prosthetic valve endocarditis is a challenge for surgeons. Echocardiography is occasionally not an effective modality for the detection of infectious signs in prosthetic valve endocarditis. Case presentation: Herein, we report the case of a patient whose prosthetic valve endocarditis was detected by multidetector computed tomography and who successfully underwent redo aortic valve replacement. Preoperative echocardiography revealed no remarkable findings related to endocarditis such as perivalvular leakage or vegetation;however, multidetector computed tomography revealed a thickened right coronary cusp. Intraoperatively, the right coronary cusp was confirmed to be covered with thick infected tissue. The pathological findings revealed broad destruction due to infection of the right coronary cusp. Conclusion: Multidetector computed tomography was useful in detecting infectious signs in prosthetic valves.

Management of the Prosthetic Valve Thrombosis: This Time Is Different

Prosthetic valve thrombosis (PVT) is a rare but serious entity. Its diagnosis and treatment can be challenging and mortality remains high regardless of its management. A 50-year-old man admitted with cardiac arrest, whose physical examination and echocardioscopy suggested PVT confirmed with fluoroscopy. Intra-aortic fibrinolysis was the treatment chosen with successful results.

VAD implantation in cardiac failure patients with prosthetic valves

Objective An increasing number of patients requiring ventricular assist devices (VAD) have had previous valvular corrections,including valve repair,and valve replacement with mechanical or bioprosthetic valves. The operative and peri-operative management of these patients are various. Methods A retrospective study of VADs between Jan 1994 and June 2008 revealed 10 patients

Replacement of degenerated prosthetic valve post apico-aortic conduit with extra corporeal membrane oxygenation

Use of an apico-aortic conduit （AAC） serves as an alternative method to treat severe aortic stenosis inelder patients, especially in those with a heavily calcified ascending aorta or prior cardiac surgery. The results of long-term follow-up of AAC are very rare. We reported a case about a successful replacement of late degenerated prosthetic valve following AAC procedure, assisted with extra corporeal membrane oxygenation （ECMO）.

The Effects of Lower Intensity Anticoagulation Therapy on Coagulation System in Patients With Mechanical Prosthetic Valves

Summary: To evaluate the effect of lower intensity anticoagulation therapy in patients with mechanical prosthetic valves, laboratory based hematological assays including prothrombin time (PT), activity of factor X, antithrombin Ⅲ (AT Ⅲ), D dimer, fibrinogen (Fg) and platel et al pha granular membrane protein (GMP 140) were performed in 65 patients who had been on warfarin treatment for over one month. The patients were assigned to 3 groups on the basis of their International Normalized Ratios (INR), ranging from 2.00 to 2.50; 2.51 to 3.00; 3.01 to 4.50, respectively. The results showed that the D dimer, Fg, GMP 140 levels were higher after mechanical valve replacement than those before operation, indicating the activation of coagulation and fibrinolysis system and the damage of platelets. Lower intensity anticoagulation therapy (INR 2 00 to 2.50) could effectively inhibit the activity of factor X and increase the level of AT Ⅲ. There were no appreciable differences among D dimer, Fg, GMP 140 and AT Ⅲ in the 3 anticoagulation intensity groups. These results suggest that in patients with new generation mechanical prosthetic valves, target anticoagulation level (INR 2 00 to 2.50) may result in good protection from thrombo embolism.

A combined anti-thrombotic therapy for thrombosis of mitral prosthetic valves

Background For patients with prosthetic heart valves, thrombosis of the valves is dangerous. A second surgery for re-replacing the thrombosed valve is quite traumatic. There have been some researches on noninva-sive therapies for thrombosis of prosthetic heart valves. But the combined anti-thrombotic therapy including anti-coagulants and anti-platelet agents was seldom studied. Methods Fourteen patients suffered from throm-bosis of the mitral prosthetic valve with stable hemodynamics were studied retrospectively. Thrombosis of the valves was demonstrated by transesophageal echocardiography. All the patients were given a combined anti- thrombotic therapy with clopidogrel and warfarin during the whole treatment with close monitoring. Low molecular weight heparin （LMWH） was given twice a day during the first 5 days of further treatment in four inpatients. Transthoracic echocardiography was performed repeatedly to observe the function of the mitral prosthetic valves and changes of the thrombus. Results This study included 4 males and 10 females. In these patients, 13 suffered from thrombosis of the mechanical mitral valves, and one patient had thrombosis of the bioprosthetic mitral valve. After an average of 32.0 - 20.4 days＇ treatment, eleven （78.6%） patients＇ thrombi disappeared thoroughly with normalized valvular function, only three （21.4%） patients＇ thrombi still existed, but no deterioration of valvular functions. For the patients with successful treatment, sizes of the left atriums decreased after treatment （P = 0.01）. No significant changes of other chambers and left ventricular ejection fraction were observed （P 〉 0.05）. None experienced major bleeding except for two cases of mild subcuta- neous hemorrhage. Conclusions The combined anti-thrombotic therapy based on clopidogrel and warfarin （plus LMWH） is a feasible treatment of thrombosis of prosthetic heart valves under a close monitoring, for both inpatients and outpatients.

Univariate Risk Factors for Prolonged Mechanical Ventilation in Patients Undergoing Prosthetic Heart Valves Replacement Surgery

Data from 736 patients undergoing prosthetic heart valve replacement surgery and concomitant surgery （combined surgery） from January 1998 to January 2004 at Union Hospital were retrospectively reviewed. Univariate logistic regression analyses were conducted to identity risk factors for prolonged mechanical ventilation. The results showed that prolonged cardiopulmonary bypass duration, prolonged aortic cross clamp time and low ejection fraction less than 50 percent （50 %） were found to be independent predictors for prolonged mechanical ventilation. Meanwhile age, weight, and preoperative hospital stay （days） were not found to be associated with prolonged mechanical ventilation. It was concluded that. for age and weight, this might be due to the lower number of old age patients （70 years and above） included in our study and genetic body structure of majority Chinese population that favor them to be in normal weight, respectively.

Imaging of pannus formation in patients with mechanical heart valves

Patient-prosthesis mismatch(PPM) should be recognized in patients with elevated transprosthetic gradients but without leaflet immobility, since the treatment strategy may differ in either etiology. However, thrombus and/or pannus formation should be excluded before a diagnosis of PPM is made. Particularly, pannus formation may not be diagnosed with 2-dimensional transesophageal echocardiography. Electrocardiographically gated 64-section multidetector computed tomography(MDCT) may be a promising tool in diagnosing or excluding pannus formation. Our report underlines the utility of MDCT in this regard and also emphasizes the importance of recognition of PPM as a differential diagnosis in such patients.

Mechanical versus biological prosthetic heart valves in pregnant women with valvular heart disease

Background The pregnant women with a prosthetic heart valve(PHV)are considered to have a higher risk of cardiovascular,obstetric and fetal/neonatal complications when they underwent anticoagulation therapy in all 3 trimesters.This report evaluated the comparative results of pregnant women wearing mechanical and biological PHV.Methods The outcomes of different types of PHV were assessed retrospectively in pregnant women in Guangdong Provincial People’s Hospital from January 2008 to May 2021.A total of 243 women(319 pregnancies)were enrolled and divided into mechanical PHV group and biological PHV group according to the types of PHV implanted.The baseline data of all pregnancies were studied.Cardiovascular,obstetric and fetal/neonatal complications in 201 completed pregnancies of 165 women with different PHV were analyzed.Results 319 pregnancies occurred,of which 201 pregnancies(165 women)≥20 weeks duration,including 159 pregnancies with mechanical PHV and 42 pregnancies with biological PHV.Miscarriages were more common in women with mechanical PHV[40 pregnancies(14.65%),≤20 weeks],while only one case was noted in women with biological PHV(P<0.05).The induced abortion rate of women with mechanical PHV(27.11%vs.6.52%,P<0.05)was significantly higher compared with that in women with biological PHV.The incidence of cardiovascular,obstetric and fetal/neonatal complications was equally frequent in both groups after 20 weeks of gestation.Conclusions Pregnant women with mechanical PHV were more likely to have a complication of miscarriages than those with biological PHV,mainly due to the anticoagulation therapy.On the other hand,more women with mechanical PHV may choose not to become pregnant than women with biological PHV after counseling the risks of pregnancy.There was no significant difference in other aspects of maternal and fetal complications after 20 weeks of gestation.Women who cannot maintain therapeutic anticoagulation and frequent monitoring of mechanical PHV may consider biological PHV.

Prosthetic venous valves for chronic venous insufficiency:Advancements and future design directions

With the serious aging population and lifestyle changes,chronic venous insufficiency accounts for approximately 25.95%of the population,which may lead to lower limb edema and leg heaviness,as well as severe infections of skin ulcers that can result in sepsis and necessitate amputation.Conservative treatment and other supportive measures can only slow the disease's progression but are unable to drastically reverse it;surgical interventions are rarely used due to the high risk of catastrophic postoperative consequences.As one of the most promising minimally invasive therapies,percutaneous prosthetic valve replacement has emerged in light of this situation,providing novel alternatives for patients with deep venous valve insufficiency.We reviewed the historical prosthetic venous valve designs,including their structure and materials,animal evaluation models,and assessment criteria.On the basis of the findings from in vitro tests,animal studies,and clinical trials,we summarized the major challenges and potential solutions for the development of advanced prosthetic venous valves.