Cardiovascular Infections

Question 1

What is endocarditis?

Answer 1

inflammation of the endocardium => needs to have both (1) active bacteremia and (2) structurally defective valves (e.g., prosthetic valve)

Question 2

What are the risk factors for endocarditis?

Answer 2

IV drug use and IV catheters (bacteremia); prosthetic valves, severe stensosis, and regurgitation (structural heart disease)

Question 3

Which pathogens are responsible for endocarditis?

Answer 3

Strep viridians and other Strep species (causes sub-acute/indolent infection: days-weeks) and Staph aureus (causes acute infection: hours-days)

Question 4

What are the S and S of endocarditis due to Strep species?

Answer 4

affinity for pharynx and gums, appear in chains or pairs in Gram stains, subacute onset, low grade fever, fatigue, murmur => slow valve destruction

Question 5

What are the S and S of endocarditis due to Staph aureus?

Answer 5

due to IV drug use or surgical procedures, cocci in clusters in Gram stain, acute onset, high grade fever, shaking, chills, murmur => rapid valve destruction

Question 6

What is the composition of a valvular vegetation?

Answer 6

fibrin, platelets, RBCs, bacteria, WBCs => causes valve destruction and can lead to systemic emboli

Question 7

How does endocarditis present?

Answer 7

fever, night sweats, new or worsening murmur => may also have symptoms of septic embolism

Question 8

What is the complication of vegetation on a right-sided valve (i.e., tricuspid)?

Answer 8

pulmonic emboli

Question 9

What is the complication of vegetation on a left-sided valve?

Answer 9

emboli can go anywhere => may see Roth spots (emboli on the retina), Janeway lesions (emboli on the palms with inflammation of blood vessels), Osler nodes (red, painful nodes on the fingers), or splinter hemorrhages (dark lines in the nail beds)

Question 10

What distinguishes endocarditis from myocarditis?

Answer 10

myocarditis is usually accompanied by CHF => S and S include fever and chest pain

Question 11

What distinguishes endocarditis from pericarditis?

Answer 11

pericarditis does not cause a murmur and never occurs without pain

Question 12

What is the best initial workup for endocarditis?

Answer 12

blood cultures - endocarditis is impossible without systemic bacteremia (95% sensitive) => negative result more likely to be false negative (Abx was given too soon)

Question 13

What is the best imaging test for endocarditis?

Answer 13

trans esophageal ECHO (TEE) - more sensitive than transthoracic ECHO (TTE) but TTE is less invasive, so start with TTE and perform TEE if TTE is negative but you have a high clinical suspicion of endocarditis

Question 14

Why is TEE better for visualizing left-sided endocarditis?

Answer 14

enters closer to left-sided valves, so is easier to visualize left-sided damage

Question 15

What establishes a Dx of endocarditis?

Answer 15

1 + blood culture AND vegetations visualized on ECHO

Question 16

How can you establish a Dx of endocarditis if blood cultures are negative?

Answer 16

document presence of fever, risk factors, embolic phenomena AND vegetations on ECHO

Question 17

What is the empiric Abx Tx for endocarditis?

Answer 17

vancomycin (covers Staph, including MRSA, but not reliable for Strep) + IV Ampicillin (for Strep) - Gentamycin can be added for synergism => change Abx based on sensitivity when culture results are available

Question 18

How long should Abx be continued for Tx of endocarditis?

Answer 18

4-6 weeks of IV Abx (vegetations take a long time to treat) => PT may need surgery for ruptured valve and embolism

Question 19

When is prophylactic Abx Tx for endocarditis warranted?

Answer 19

PT must be undergoing high risk procedure and have both (1) significant valvular defect (prosthetic valve, previous endocarditis, unrepaired/partially repaired cyanotic heart defect) AND (2) risk of bacteremia: dental work or respiratory tract work with blood (tooth extraction, root canal, dental cleaning, biopsy, tonsillectomy)

Question 20

What is the recommended prophylaxis for endocarditis?

Answer 20

amoxicillin or clindamycin (single dose before procedure)

Question 21

What is pericarditis?

Answer 21

infection/inflammation of the pericardium

Question 22

What causes pericarditis?

Answer 22

anything that affects or damages the heart and irritates the pericardium - viral infection (most common), autoimmune disorders, malignancy, metabolic causes, chest trauma

Question 23

What is the typical presentation of pericarditis?

Answer 23

fever, friction rub, murmur, and pleuritic (sharp and stabbing) chest pain that is relieved by sitting forward - worse laying down or taking a deep breath (pericardium is stretched)

Question 24

What is a risk associated with pericardial effusion?

Answer 24

cardiac tamponade (compression of heart due to build up of fluid in pericardial sac) - rate of fluid accumulation is more important than the amount

Question 25

What is the best initial test for pericarditis?

Answer 25

ECG demonstrates the electrical activity of the heart - should be the first test for any type of chest pain (rules out MI)

Question 26

When would you use an ECHO in a PT with suspected pericarditis?

Answer 26

ECHO shows structural changes in the heart - use it to rule out pericardial effusion (fluid in the pericardial sac - won’t hear a friction rub, sounds will be muffled due to fluid)

Question 27

What are the typical ECG changes in pericarditis?

Answer 27

diffuse (seen in multiple leads) concave ST elevations and PR depressions

Question 28

What is the Tx for pericarditis?

Answer 28

supportive with first presentation: NSAIDs with or without Colchicine (side effects of diarrhea and abdominal pain) - steroids if insufficient response to NSAIDs => should resolve in 2-6 weeks

Question 29

Which valve is most commonly affected in IV drug users with endocardits?

Answer 29

tricuspid

Question 30

What are the S and S of myocarditis?

Answer 30

chest pain, arrhythmia, symptoms of heart failure (SOB, lower extremity edema)