Prosthetic valves are increasingly encountered in clinical practice. A grasp of the intricacies of the assessment and management of prosthetic valves is thus a crucial skillset for the practicing cardiologist. Echocardiography is the imaging modality of choice for the anatomic and functional evaluation of prosthetic valve. This document reviews the general features of prosthetic valves, echocardiographic identification of normally functioning and dysfunctional prosthetic valves as well as echocardiographic diagnosis of specific prosthetic valvular abnormalities.

BACKGROUND: Valvular heart disease presents a significant and escalating global health challenge. Prosthetic valve thrombosis (PVT) following surgical valve replacement is a primary cause of valve failure. The aim of this study was to ascertain the outcomes and complications of fibrinolytic therapy in patients diagnosed with PVT.
METHODS: This cross-sectional study enrolled 81 patients diagnosed with PVT who underwent fibrinolytic therapy between 2008 and 2018. Streptokinase was administered to 87.6% of patients, while 12.4% received reteplase. All demographic and clinical data were gathered from the patients\' medical records. The incidence of successful recovery and complications were assessed.
RESULTS: The records of 81 patients (43.2% male, mean age: 51.6 ± 13.9 years) were examined. The findings revealed that 59% and 35% of the patients had mitral and aortic PVT, respectively. While 12% of the patients experienced drug complications, 90% achieved successful recovery. Stroke and severe hemorrhage were complications frequently reported by the patients treated with streptokinase (8% and 4% respectively). The patients treated with reteplase demonstrated a 100% recovery rate. Conversely, 89% of the patients treated with streptokinase achieved successful recovery, and 7% of the patients experienced a partial recovery.
CONCLUSIONS: Fibrinolytic agents can serve as an effective treatment with an excellent success rate for managing PVT in patients post-surgical valve replacement.

Mechanical prosthetic valve thrombosis (PVT) and obstruction are rare and dangerous events often related to inappropriate anticoagulant therapy. High mortality rates occur because of delayed diagnosis, hemodynamic instability, multiple organ failure (MOF), and high perioperative risk. Surgical repair is a first-line treatment for obstructive PVT with hemodynamic instability but is often not readily available or safely performed. Venoarterial extracorporeal membrane oxygenation (VA ECMO) support has been increasingly used in patients with PVT and cardiorespiratory collapse, allowing MOF reversal and safer deferred surgery. The authors present a case of a young female with refractory cardiogenic shock secondary to mitral PVT successfully managed with VA ECMO. Furthermore, the promising role of perioperative VA ECMO support for PVT-related cardiogenic shock is also discussed.

A 68-year-old woman with history of aortic valve replacement developed severe heart failure and cardiac arrest. Transesophageal echocardiography and cardiac computed tomography showed mechanical aortic valve thrombosis. Low-dose, ultraslow infusion of tissue-plasminogen activator was performed while the patient was in a critically ill condition, resulting in the improvement of thrombus burden and structural valve deterioration.
UNASSIGNED: Mechanical valve thrombosis can be an underlying mechanism of severe heart failure, in which systemic thrombolytic therapy in a low-dose, ultraslow, and prolonged manner may improve clinical outcomes, even in critically ill patients.

A 37-year-old woman with mechanical tricuspid valve thrombosis presented for preconception consultation. Multimodality imaging confirmed a malfunctioning bileaflet mechanical tricuspid valve with both leaflets fixed and open. This case highlights the key discussions held by the multidisciplinary pregnancy heart team.

UNASSIGNED: The use of anticoagulation is mandatory for prevention of prosthetic valve thrombosis (PVT) worldwide, regardless of the valve type or position in the heart. In case a thrombosis causes symptomatic dysfunction, treatment usually includes the use of thrombolytic therapy or surgery. We report a case of PVT involving a patient with a mechanical aortic valve which was treated entirely with the use of anticoagulation therapy (warfarin).
UNASSIGNED: A 58-year-old man had an aortic valve replacement using a Carbomedics® mechanical valve due to severe aortic stenosis as a result of a calcific bicuspid native aortic valve. He was commenced on warfarin after surgery which was continued thereafter. He presented to our hospital after three years with shortness of breath at rest. On clinical examination, his condition was poor with a New York Heart Association functional classification of IV. He was in sinus rhythm and had an enlarged heart shadow on chest X-ray. Transesophageal echocardiography (TEE) revealed aortic valve regurgitation with vegetations on the anterior valve leaflet causing reduced hemi leaflet motility and a mean pressure gradient of 50 mmHg. Cinefluoroscopy revealed a dysfunctional mechanical valve leaflet. Surgery was at high risk of mortality due to the patient\'s clinical status and he was continued on warfarin therapy with close monitoring. Cinefluoroscopy and echocardiography done six months later revealed complete dissolution of thrombus and a normally functioning mechanical aortic valve.
UNASSIGNED: Only a few cases of symptomatic, thrombotic mechanical aortic valve were entirely treated with anticoagulation only. Our patient is one such case who had resolution of symptoms and improvement on NYHA functional classification (IV to I).

BACKGROUND: Heart valve replacement surgery with mechanical or biological prostheses entails a risk of thromboembolism and bleeding complications.
OBJECTIVE: To determine the complications related to complementary anticoagulation therapy and the probability of risk.
METHODS: One-hundred and sixty-three patients who underwent heart valve replacement between 2002 and 2016 with either mechanical or biological prostheses, and who received vitamin K antagonists after hospital discharge, were studied. Anticoagulation therapy was categorized into optimal and non-optimal according to INR values prior to the development of complications. Patients with comorbidities and other risk factors for thrombosis and/or bleeding were excluded.
RESULTS: In total, 68.7 % of patients received mechanical prostheses, and 31.3 %, biological prostheses (p ≤ 0.001); 25.2 % experienced the complications that motivated the study (p ≤ 0.001), which were hemorrhagic in 48.8 %, thromboembolic in 26.8 %, and of both types in 24.4 % (relative risk = 4.229). Among the patients with complications, 95.1 % received mechanical prostheses, and 4.9 %, biological (p = 0.005); non-optimal INR was identified in 49.7 % (p ≤ 0.001).
CONCLUSIONS: Given the high risk of thromboembolic and hemorrhagic complications, valve prostheses must be carefully chosen, and care priorities should include prevention and follow-up, especially in those patients who require anticoagulation therapy.
BACKGROUND: El reemplazo valvular por prótesis mecánicas o biológicas implica riesgo de tromboembolismo y complicaciones hemorrágicas.
OBJECTIVE: Determinar las complicaciones relacionadas con la terapia de anticoagulación complementaria y la probabilidad de riesgo en pacientes portadores de prótesis valvulares del corazón.
UNASSIGNED: Se estudiaron 163 pacientes entre 2002 y 2016, portadores de prótesis mecánicas y biológicas, quienes recibieron antagonistas de la vitamina K posterior al egreso hospitalario. La terapia de anticoagulación se categorizó en óptima y no óptima conforme a los valores de INR previos a las complicaciones. Fueron excluidos los pacientes con comorbilidades y otros factores de riesgo de trombosis y/o sangrado.
RESULTS: a 68.7 % de los pacientes se les colocó prótesis mecánica y a 31.3 %, biológica (p ≤ 0.001); 25.2 % presentó las complicaciones motivo de estudio (p ≤ 0.001), hemorrágicas en 48.8 %, tromboembólicas en 26.8 % y de ambos tipos en 24.4 % (riesgo relativo = 4.229); a 95.1 % de los pacientes con complicaciones se les colocó prótesis mecánica y a 4.9 %, biológica (p = 0.005); 49.7 % presentó INR no óptimo (p ≤ 0.001).
CONCLUSIONS: Ante riesgo alto de complicaciones tromboembólicas y hemorrágicas, la elección de las prótesis valvulares, la prevención y el seguimiento son prioridades, principalmente en quienes requieren terapia de anticoagulación.

UNASSIGNED: Prosthetic valve thrombosis (PVT) is a rare but one of the most dreaded complications of implanted mechanical valves. Although surgery is the first-line treatment modality particularly in symptomatic obstructive mechanical valve thrombosis, it is associated with high rates of morbidity and mortality. Thrombolytic therapy has also been used as an alternative to surgical treatment. The risk for cerebral thromboembolism associated with thrombolytic therapy seems to be the main limitation for its use in left-sided mechanical valve thrombosis. To the best of our knowledge, this is the first case of implantation of embolic protection devices during thrombolytic therapy of PVT.
UNASSIGNED: Our report describes management of patient with obstructive PVT of the aortic valve. Fluoroscopy showed an immobile anterior disc of the aortic prosthesis. Transoesophageal echocardiography (TOE) detected the severely restricted prosthetic valve motions and a huge mass at the supravalvular site. A patient had very high surgical risks. Although, thrombolytic treatment was not without risk due to the large thrombus (>10 mm) increasing the risk of thromboembolism. We implanted embolic protection devices into both internal carotid arteries followed by the administration of a thrombolytic therapy with 50 mg Alteplase. After the procedure an embolized thrombus was detected at the apex at the left-sided placed device. There were no signs of transient ischaemic attack nor stroke, and the procedure was ended uneventful. The TOE performed on the next day confirmed successful resolution of the thrombus.
UNASSIGNED: Mechanical left-sided prosthetic valve obstruction is a serious complication with high mortality and morbidity and requires urgent therapy. The choice between surgery, thrombolysis, and escalation of anticoagulation is considered on an individual basis. In patients with high surgical risk and high risk of embolization, an embolic protection device may be used in conjunction with thrombolytic therapy to decrease the risk of embolic cerebral events.

BACKGROUND: Nearly half of the patients with hypereosinophilic syndrome (HES) have cardiovascular involvement, a major cause of mortality. COVID-19 infection can lead to cardiac involvement, negatively impacting the clinical course and prognosis. We reported two patients with HES complicated by COVID-19, with cardiac involvement and valve replacement.
METHODS: Our first patient was a 27-year-old woman admitted due to dyspnea and signs of heart failure. She had severe mitral stenosis and mitral regurgitation on the echocardiogram. Corticosteroid therapy improved her symptoms initially, but she deteriorated following a positive COVID-19 test. A repeated echocardiogram showed right ventricular failure, severe mitral regurgitation, and torrential tricuspid regurgitation and, she underwent mitral and tricuspid valve replacement. Our second patient was a 43-year-old man with HES resulted in severe tricuspid stenosis, which was improved with corticosteroid treatment. He underwent tricuspid valve replacement due to severe valvular regurgitation. He was admitted again following tricuspid prosthetic mechanical valve thrombosis. Initial workups revealed lung involvement in favor of COVID-19 infection, and his PCR test was positive.
CONCLUSIONS: COVID-19 infection can change the clinical course of HES. It may result in a heart failure exacerbation due to myocardial injury and an increased risk of thrombosis in prosthetic valves or native vessels due to hypercoagulability.

UNASSIGNED: Valve thrombosis is a well-documented cause of bioprosthetic valve failure. Case reports have been published of prosthetic valve thrombosis secondary to COVID-19 infection. This is the first case report of COVID-19 associated valve thrombosis in a patient with transcatheter aortic valve replacement (TAVR).
UNASSIGNED: A 90-year-old female with atrial fibrillation on therapeutic apixaban and status-post TAVR presented with COVID-19 infection and was found to have severe bioprosthetic valvular regurgitation with features suggestive of valve thrombosis. She underwent valve-in-valve TAVR with resolution of valvular dysfunction.
UNASSIGNED: This case report contributes to a growing body of evidence describing the occurrence of thrombotic complications in patients with valve replacement and COVID-19 infection. Increased vigilance and continued investigation are warranted to better characterize thrombotic risk and to inform optimal antithrombotic strategies during COVID-19 infection.