Makindo Medical Notes

🫀 Marantic endocarditis (non-bacterial thrombotic endocarditis, NBTE) is defined by sterile platelet–fibrin vegetations on cardiac valves. ⚖️ Strongly linked to a hypercoagulable state, especially in advanced malignancy. 🚑 Clinical significance often lies in recurrent systemic emboli rather than valve destruction.

ℹ️ About

• Occurs mainly in patients with advanced cancer (especially adenocarcinoma) or chronic debilitating disease.
• Represents part of the Trousseau syndrome spectrum of malignancy-associated thrombosis.

🧬 Causes

• Solid Tumors: Pancreatic, gastric, and lung adenocarcinomas are most common.
• Hematologic Malignancies: Leukemias (e.g., acute promyelocytic leukemia).
• Other States: Severe sepsis, systemic lupus erythematosus (Libman–Sacks overlap), chronic wasting disease.

🔬 Pathology

• Small, friable, sterile vegetations along valve closure lines (most often mitral and aortic valves).
• Histology shows fibrin + platelet aggregates without inflammatory cells or organisms.
• Vegetations embolize easily → systemic infarcts (brain, spleen, kidneys).

🩺 Clinical Features

• Murmur: Often subtle, sometimes absent, as vegetations are small.
• Embolic Phenomena: Ischemic stroke 🧠, renal infarcts 🧽, splenic infarcts 🍐, digital ischemia.
• Heart Failure: Rare, unless vegetations cause significant valve regurgitation.

🧪 Investigations

• Blood Tests:
  • FBC → anaemia of chronic disease.
  • Raised ESR/CRP due to underlying malignancy.
• Blood Cultures: Sterile ❌ (contrast with infective endocarditis).
• Echocardiography: TTE/TEE may detect small vegetations; TEE is more sensitive.
• ECG: Non-specific; may show changes if embolic MI or atrial fibrillation complicates course.

💊 Management

• Anticoagulation: Heparin (LMWH preferred over warfarin) may reduce embolic risk. Warfarin less effective in malignancy-associated thrombosis.
• Oncology Treatment: Treating the underlying malignancy is the only definitive strategy.
• Palliative Approach: Supportive care often appropriate due to poor prognosis.
• Surgery: Rare; valve replacement considered only if embolic risk is extreme and life expectancy otherwise reasonable.

📚 Exam Tips: 👉 NBTE = malignancy + sterile vegetations + recurrent emboli. 👉 Differentiate from infective endocarditis: sterile cultures, lack of fever/systemic infection. 👉 Think “stroke in a cancer patient” → always consider NBTE.