Prosthetic valve thrombosis
Prosthetic valve thrombosis is thrombus on a prosthetic valve, most often a mechanical valve with inadequate anticoagulation, causing obstruction or embolism. It presents with heart failure, muffled prosthetic sounds, or embolic events, is confirmed by echocardiography and fluoroscopy, and is treated by surgery or fibrinolysis depending on severity.
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What this article covers
- Overview
Definition: prosthetic valve thrombosis is the formation of thrombus on a prosthetic heart valve, impairing leaflet or disc motion (obstruction) or causing embolism.
- Epidemiology
Predominantly affects mechanical valves, especially in the mitral position.
- Risk factors
Subtherapeutic or interrupted anticoagulation (the dominant risk).
- Pathophysiology
Thrombus on prosthetic material: stasis and inadequate anticoagulation allow thrombus to form on the sewing ring, discs, or leaflets.
- Clinical features
Exertional dyspnea and heart failure from obstruction.
- Differential diagnosis
Prosthetic valve endocarditis: infection with vegetations, positive blood cultures, and fever rather than bland thrombus (Prosthetic valve endocarditis).
- Diagnosis
Establish with echocardiography and fluoroscopy showing restricted leaflet or disc motion and thrombus, and distinguish from pannus and vegetation: the diagnostic basis is transthoracic and…
- Management
First-line, stratify by severity, side, thrombus size, and symptoms: obstructive left-sided thrombosis with heart failure is a surgical emergency in suitable patients.
- Complications
Acute valve obstruction, heart failure, and cardiogenic shock.
- Prognosis
Life-threatening when obstructive, with better outcomes after prompt treatment.
- Prevention
Maintain therapeutic anticoagulation at the valve-specific INR target (2.5 to 3.5 for most mechanical valves) with warfarin (not DOACs), monitored every 4 weeks.
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Related articles
- Prosthetic valve endocarditis
Prosthetic valve endocarditis is infection of a prosthetic heart valve, classified as early or late by time from surgery, and it is more aggressive and harder to treat than native valve disease. It commonly causes perivalvular abscess and dehiscence, requires transesophageal echocardiography and prolonged antibiotics, and often needs surgery.
- Mitral stenosis
Mitral stenosis is obstruction of left atrial emptying from a narrowed mitral valve, overwhelmingly rheumatic in origin. It causes left atrial hypertension, atrial fibrillation, and pulmonary congestion, with a diastolic rumble and opening snap; severe symptomatic disease is treated with percutaneous balloon valvuloplasty or valve surgery.
- Aortic stenosis
Aortic stenosis is obstruction to left ventricular outflow from a narrowed aortic valve, most often calcific degeneration in older adults or a bicentric bicuspid valve earlier in life. Symptoms of angina, syncope, or heart failure mark a poor prognosis, and severe symptomatic disease is treated with valve replacement (surgical or transcatheter).
- Nonbacterial thrombotic endocarditis
Nonbacterial thrombotic endocarditis (marantic endocarditis) is sterile platelet-fibrin vegetations on cardiac valves associated with malignancy and autoimmune disease, notably antiphospholipid syndrome and lupus (Libman-Sacks). It rarely destroys valves but embolizes readily, so treatment is anticoagulation and management of the underlying disease.