Cardiac Vegetations: Differential Diagnosis
Distinguishing between different types of cardiac valve vegetations is a classic pathology board examination topic. The key lies in the location of the vegetation and the clinical context of the patient.
| Vegetation Type | Location | Key Features |
|---|---|---|
| Infective Endocarditis | Any side (large, friable) | Destructive, embolize easily. Associated with fever/bacteremia. |
| Libman-Sacks (SLE) | Both sides of valve | Sterile, immune-complex mediated. Associated with SLE. |
| Nonbacterial Thrombotic (NBTE) | Line of closure | Sterile, bland thrombi. Associated with hypercoagulable states (e.g., advanced malignancy). |
| Rheumatic Fever | Line of closure | Small, verrucous. Associated with acute rheumatic fever. |
High-Yield Clinical Pearls
- IE vs. Libman-Sacks: In infective endocarditis, vegetations are typically destructive and located on the atrial side of AV valves (or ventricular side of semilunar valves). In Libman-Sacks, they occur on both surfaces of the leaflets.
- NBTE (Marantic): Remember the association with adenocarcinoma (mucin production) and chronic wasting diseases. These are “bland” because they lack inflammation.
- Rheumatic Fever: The vegetations in acute rheumatic fever are small and wart-like (verrucous), found along the lines of leaflet closure.
Pathology Board Hint: If a vignette describes a “sterile” vegetation in a patient with a known malignancy, choose NBTE. If it’s a patient with systemic lupus erythematosus, look for Libman-Sacks.