Infective Endocarditis

Question 1

Most common cause of Infective Endocarditis (IE).

Answer 1

Staph aureus

Question 2

Major cause of early Prosthetic Valve IE.

Answer 2

Staph epidermidis

Question 3

Major cause of late Prosthetic Valve IE

Answer 3

Viridans strep

Question 4

Major cause of IE in IVDU

Answer 4

Staph aureus

Question 5

How does IE presentation differ in IVDU vs. non-IVDU?

Answer 5

In IVDU the Right side of the heart is affected, mainly the tricuspid valve. Also the peripheral manifestations are absent because the lungs are affected first.

Question 6

Explain the pathogenesis of IE.

Answer 6

1. Endocardial Injury Occurs (except in IVDU)
2. Fibrin-platelet clot forms (NBTE)
3. Microbes enter circulation
4. Microbes attach to the clot
   4.

Question 7

What are the 3 necessary components to make a diagnosis of IE?

Answer 7

1. Thorough H and P
2. Blood Cultures
3. Echocardiogram

Question 8

What is the most sensitive symptom and most reliable sign for IE?

Answer 8

SS: fever
RS: murmur

Question 9

Name the 5 peripheral signs (stigmata) associated with IE.

Answer 9

1. Petechiae (mainly in mouth, conjunctiva, upper extremities)
2. Splinter Hemorrhages (under fingernails)
3. Osler Nodes (found on finger and toe pads)
4. Janeway Lesions (found on palms and soles)
5. Roth Spots (retinal hemorrhages)

Question 10

Describe the pathogenesis of mycotic aneurysms and problematic spots where they occur.

Answer 10

Vegetations occur in the heart due to IE. These break off and block the vasa vasorum.
The vessel walls start to weaken and an aneurysm forms.

These can occur in the aorta or even the cerebral arteries.

Question 11

What is important to remember b/4 starting antibiotics?

Answer 11

Blood culture for definitive Dx.

Question 12

What is the standard antibiotic regimen for IE?

Answer 12

4-6 weeks

sometimes valve replacement necessary

Question 13

What are three indications for emergency valve replacement surgery?

Answer 13

1. Acute aortic insufficiency with early closure of the mitral valve
2. Rupture of sinus of Valsalva into right-heart chamber
3. Rupture of sinus of Valsalva into pericardium

Question 14

Which 4 groups is there recommended antibiotic prophylaxis for IE?

Answer 14

1. Prosthetic Valves
2. Previous IE
3. Congenital Cardiac Issue
4. Cardiac Transplant