Infective endocarditis

Question 1

Risk factors for IE

Answer 1

Age > 60
Male
IVDU
Poor dentition/dental infection

Comorbidities (structural heart disease, valvular disease, CHD, CABG)

Immunosuppression/HIV/chronic haemodialysis

Foreign bodies - IVC, CIED

Question 2

Anticoagulant therapy in infective endocarditis

Answer 2

Anticoagulation and anti-platelet agents have NOT been shown to reduce the risk of embolism in IE

In addition to embolism, IE carries the competing risk of intracranial haemorrhage!

Anticoagulants should not be given to an IE patient UNLESS they have a strong, genuine indication (i.e. mechanical prosthetic valves) and benefits > risks

Question 3

Clinical features of infective endocarditis

Answer 3

Highly variable
Acute and rapidly progressive, subacute OR chronic disease with fever and non-specific sx

Most common sx is fever (90%)

Other symptoms: malaise, headache, myalgias, arthralgias, night sweats, abdominal pain, SOB, cough, pleuritic pain

Question 4

How many patients with IE have cardiac murmurs?

Answer 4

85% of patients

Question 5

Examination findings IE

Answer 5

General:
Febrile, IVDU

Hands/feet:

• Janeway lesions (macules, non painful, palms and soles - septic emboli therefore more common in acute)
• Osler nodes (tender, purple, pads of fingers and toes - inflammatory immune complex - therefore more common in cubacute)

Eyes:
- Roth spots (haemorrhagic lesions of retina w pale centres)

Heart: cardiac murmurs

Complications as examination findings:

• Cardiac: valvular insufficiency, heart failure
• Neurologic: stroke, ICH, brain abscess
• Septic emboli of other organs
• Metastatic infection: vertebral OM, septic arthritis, abscesses
• Systemic immune response: GN

Question 6

Complications of IE

Answer 6

• Cardiac: valvular insufficiency, heart failure
• Neurologic: stroke, ICH, brain abscess
• Septic emboli of other organs
• Metastatic infection: vertebral OM, septic arthritis, abscesses
• Systemic immune response: GN

Question 7

Diagnosis of IE - definite on criteria

Answer 7

Modified Duke Criteria
Pathologic and clinical

Definite IE:

• 2 major criteria OR
• 1 major and 3 minor criteria OR
• 5 minor criteria

Question 8

Major Duke Criteria

Answer 8

1. Positive blood cultures for IE (typical organisms, persistently positive)
2. Evidence of endocardial involvement (vegetation, abscess, new partial dehiscence of prosthetic valve) or new valvular regurgitation

Question 9

Minor Duke Criteria

Answer 9

1. Predisposition: IVDU, predisposing heart condition
2. Fever > 38
3. Vascular phenomena: arterial emboli, septic pulmonary infarcts, mycotic aneurysm, ICH, conjunctival haemorrhages, janeway lesions
4. Immunologic phenomena: GN, oslers nodes, roth spots, RHf`
5. Microbiologic: BCs that don’t meeet major, or serologic evidence of active infection consistent with IE

Question 10

Typical microorganisms consistent with IE

Answer 10

Staph aureus
Viridans strep 
Strep gallolyticus (formerly s. bovis)
HACEK group 
Enterococci

Question 11

Biggest risk factor for IE

Answer 11

Previous IE

Question 12

Three main indications for surgery

Answer 12

1. Acute heart failure
2. Uncontrolled infection
3. Prevention of embolic events

Question 13

Why do a doppler USS prior to a TOE?

Answer 13

Oesophageal varices are a contraindication for a TOE… If PHx ETOH use, cirrhosis, concern for varices – do a abdo doppler USS prior to TOE