Infective Endocarditis + other heart conditions

Question 1

Define bacteremia

Answer 1

bacteria in the blood

Question 2

What is infective endocarditits?

Answer 2

Infection of the endothelium of the heart valves

Question 3

Name some predisposing factors of infective endocarditis?

Answer 3

Heart valve abnormality
­  calcification/sclerosis in elderly
­  congenital heart disease – change in flow dynamics
 ­ post rheumatic fever
Prosthetic heart valve 
Intravenous drug users
Intravascular lines

Question 4

Outline the pathogenesis?

Answer 4

o Heart valve damaged
o Turbulent blood flow over roughened endothelium
o Platelets / fibrin deposited
o Bacteraemia (may be very transient) e.g. from dental treatment
o organisms settle in fibrin/platelet thrombi becoming a microbial vegetation
o Infected vegetations are friable and break off, becoming lodged in the next capillary bed they encounter causing abscesses or haemorrhage - may be fatal
o Usually left side of heart affected (mitral and aortic valves)

Question 5

What are the most common organisms causing infective endocarditis?

Answer 5

Staphylococcus aureus (38%)
Viridans streptococci (31%)
Enterococcus sp (8%)
Staph epidermidis (6%)

Question 6

Name a few unusual organisms that can cause infective endocarditis?

Answer 6

Atypical organisms
- Bartonella, Coxiella burnetii (Q-fever), Chlamydia, Legionella, Mycoplasma, Brucella
Gram-negatives
­HACEK organisms – EXAMS
- Haemophilus spp. , Aggregatibacter spp, ( was Actinobacillus) , Cardiobacterium, Eikenella sp., Kingella sp.
- Non HACEK gram negatives
Fungi

Question 7

What is the criteria used to diagnose infective endocarditis?

Answer 7

Modified Dukes Criteria

Question 8

How do you diagnose infective endocarditis?

Answer 8

ECHOcardiogram: Transthoracic or Transoesophageal echo

Take 3 sets of blood cultures

Question 9

What is the presentation of acute infective endocarditis?

Answer 9

overwhelming sepsis and cardiac failure

Question 10

What are the symptoms of subacute infective endocarditis?

Answer 10

Fever
malaise
Weight loss
Tiredness
Breathlessness
NEW MURMUR

Question 11

What are the clinical signs of subacute infective endocarditis?

Answer 11

Fever
New or changing heart murmur
finger clubbing
splinter haemorrhages
splenomegaly
Roth spots, Janeway lesions, Osler nodesmicroscopic haematuria

Question 12

What is the antibiotic treatment for native valve endocarditis, viridans strep?

Answer 12

Amoxicillin & gentamicin IV

Question 13

What is the antibiotic treatment and normal for prosthetic valve endocarditis?

Answer 13

Vancomycin & gentamicin IV
Add in day 3 to 5 (delayed) rifampicin PO
often valve replacement is required

Question 14

What is the antibiotic used to treat drug injector endocarditis?

Answer 14

Flucloxacillin IV

Question 15

What is myocarditis?

Answer 15

inflammation of the heart muscle

Question 16

What are the signs and symptoms of myocarditis?

Answer 16

Symptoms -fever, chest pain, shortness of breath, palpitations
Signs -arrhythmia, cardiac failure

Question 17

What mainly causes myocarditis?

Answer 17

enteroviruses -Coxsackie A & B, echovirus

Question 18

What is the diagnositic procedures for myocarditis?

Answer 18

Diagnosed by viral PCR
Throat swab and stool for enteroviruses
Throat swab for influenza

Question 19

What is the most common cause of pericarditis?

Answer 19

Viral

Question 20

What is the main symptom of pericarditis?

Answer 20

chest pain