Infective Endocarditis

Question 1

What are risk factors?

Answer 1

Previous episode
Rheumatic valve disease
IVDU
Prosthetic valves
Congenital heart defects

Mitral valve most commonly affected

Question 2

What are common causative organisms?

Answer 2

Staph aureus= most common
Staph epidermis- most common post valve surgery
Strep Viridians= following dental work or poor dental hygiene
Strep Bovis- most common in colorectal cancer

Question 3

How is it diagnosed?

Answer 3

Duke Criteria

Major Features
- positive blood culture or serology
-evidence of endocardial involvement e.g. new valve regurg/ +ve ECHO

Minor
- History of CVD/IVDU
- Pyrexia >38 degrees
- Vascular phenomena e.g. septic emboli
- Immunological phenomona e.g. osler nodes/roth spots

Question 4

What are examination findings?

Answer 4

Janeway lesions- irregular non tender haemorrhagic nodules on palms and soles
Osler nodes- tender lesions on fingers/toes
Roth spots- white centred retinal haemorrhages

Question 5

What are the inevestigations?

Answer 5

TTE initial investigation= less invasive
TOE more sensitive/specific
- used if high clinical suspicion despite negative TTE or results of TTE uncertain, prosthetic valve, +ve TTE but ?complication

Question 6

What is the management?

Answer 6

Prophylaxis not recommended

Blind therapy
Native valve- amoxicillin (consider gent)
Prosthetic- consider Vanc, Gent and rifampicin

If Staph
- Native valve- fluclox
- Prosthetic- fluclox, gent and rifampicin

Strep
-benpen

Question 7

When should surgery be considered?

Answer 7

Severe valve incompetence
Cardiac failure refractory to medical treatment
Presence of aortic abscess- PR prolongation on ECG