My 8 yr old daughter has had a vegitation removed from her left ventrical. but blood results say no infection?

ENDOCARDITIS: Noninfective endocarditis refers to formation of sterile platelet and fibrin thrombi on cardiac valves due to vasculitis, trauma, immune complexes, etc.Dx is by echo and negative blood cultures.

Culture negative veg: Several reasons 1. Bland vegetation (from tumor or clot without infection present) 2. On antibiotics (if she was on antibiotics the infection may be eradicated or suppressed. 3. Blood culture may be negative because at the time they were taken the vegie was not shedding organisms (thats why we do alot of blood cultures); vegie may still grow organisms. 4.Hard to organisms on routine cultures.