Infective Endocarditis and Rheumatic Heart Disease Flashcards
What structures of the heart can endocarditis affect?
Heart valves (native/prosthetic)
Interventricular septum
Chordae tendinae
Intra-cardiac devices
What different types of staff may be involved in dealing with endocarditis?
Primary care/acute physicians Cardiologists Surgeons Microbiologists Infectious disease Neurologist/neurosurgeons Radiologist Pathologist
What are the cardiac risk factors for infective endocarditis?
Mitral valve prolapse (+/- MR) VSD Aortic Stenosis Prosthetic Heart Valve Rheumatic Heart Disease Cardiac surgery
What are the non-cardiac risk factors for infective endocarditis?
IVDA Indwelling medical devices Diabetes AIDS Chronic skin conditions Genito-urinary infections Alcoholic cirrhosis GIT lesions Solid organ transplant Homelessness Pneumonia/meningitis Dog/cat exposure
What is the pathophysiology of infective endocarditis?
Can be from adherence and invasion of non-bacterial thrombotic endocarditis
- a sterile fibrin-platelet vegetation
Can be from mechanical disruption of valve endothelium
- turbulent blood flow
- electrodes
- catheters
- inflammation
- degeneration
- favours infection
Can also have physically normal endothelium with local inflammation
Bacteraemia also possible
- extra-cardiac infections
- invasive procedures
- gingival disease
How is IE classified?
Acute
Subacute
Chronic
Localisation/Intracardiac material
- native or prosthetic?
- right or left?
Mode of acquisition
- healthcare related
- community acquired
- IVDA
What are the symptoms and signs of IE?
Variable presentation Bacteraemic episode Fever Fatigue Malaise
Congestive HF
Vascular/immunological phenomena
Embolism
New murmur
What is the diagnostic criteria for IE?
Modified Duke Criteria
Definite if 2 major or 1 + 3 minor
Possible of 1 major or 3 minor
Major
- typical IE organisms from 2 cultures
- +ve coxiella culture
- evidence of endocardial involvement - new murmur
Minor
- predispotion factors
- fever
- immunological phenomena
- vascular phenomena
- microbiological evidence (that isn’t major)
What investigations might be done in suspected IE?
Markers of infection
- FBC (neutrophilia)
- CRP
- ESR (erythrocyte sedimentation rate)
U+Es
- nephritis
- infection
- sepsis
Blood cultures
- prior to antibiotics
- 3 sets
- different sites
- 6+ hours between
- in severe sepsis, 2 sets from different sites within 1 hour
Urinalysis
- +ve blood
ECG CXR Echo - TTE - 1st - TOE - If TTE normal but high suspicion, or TTE +ve
What are the main organisms associated with IE?
Streptococci
Enterococci
Staphylococcus
What other organisms may be involved in IE?
Brucella
Fungi
Coxiela
Bartonella
Chlamydia
What is the treatment in IE? How does it change depending on type of IE?
IV Antibiotics (as soon as cultures taken) Aminoglycosides synergise with cell wall inhibitors
Surgery considered
Native valves
- IV gentamicin and amoxicillin 4w
- sepsis? gentamicin and vancomycin (used if penicillin allergic or MRSA +ve)
Prosthetic valves
- gentamicin and vancomycin + rifampicin 6w
Dual antifungals if fungal, often long-term (sometimes for life)
What monitoring is done during IE treatment?
Daily DBC, U+E, CRP
ECG 1-2 days
Echo weekly
What are some complications of IE?
Heart failure Fistula formation Leaflet perforation Uncontrolled infection Abscess AV heart block Embolism Prosthetic valve dysfunction
When is surgery considered in IE?
Heart failure Fistula formation Leaflet perforation/obstruction Uncontrolled infefction Enlarging vegetation Abscess AB heart block Embolism + vegetation >10mm Isolated vegetation >15mm
