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.
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What this article covers
- Overview
Definition: nonbacterial thrombotic endocarditis (NBTE, marantic endocarditis) is the formation of sterile vegetations of platelets and fibrin on cardiac valves in the absence of infection.
- Epidemiology
Associated with advanced malignancy (especially adenocarcinomas) and hypercoagulable states.
- Risk factors
Advanced or mucin-producing malignancy (pancreatic, lung, gastric, ovarian).
- Pathophysiology
Hypercoagulability and endothelial injury: a procoagulant, inflammatory state promotes deposition of platelet-fibrin thrombi on valve surfaces.
- Clinical features
Embolic events: stroke, and splenic, renal, coronary, or peripheral infarction.
- Differential diagnosis
Infective endocarditis: infected vegetations with positive blood cultures, fever, and valve destruction, unlike the sterile culture-negative vegetations of NBTE (Bacterial infective endocarditis).
- Diagnosis
Establish by valvular vegetations with persistently negative blood cultures in a patient with malignancy or autoimmune disease: the diagnostic basis is echocardiographic vegetations (often small…
- Management
First-line, anticoagulate to prevent further embolism (parenteral anticoagulation is generally preferred over an oral vitamin K antagonist in malignancy-associated disease), continued long term…
- Complications
Recurrent systemic embolism and infarction (stroke, organ, and limb).
- Prognosis
Largely determined by the underlying disease, often poor with advanced malignancy.
- Prevention
Anticoagulation to prevent recurrent embolism.
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