Infective endocarditis

Question 1

What is infective endocarditis?

Answer 1

Infectious disease of the heart and surrounding vessels

Question 2

What are risk factors of infective endocarditis?

Answer 2

Congenital heart diseases
IVDU
Invasive instrumentation procedures
Dental procedures 
Indwelling prosthetic material

Question 3

What are the most common underlying congenital heart diseases causing infective endocarditis?

Answer 3

VSD
PDA
Aortic valve - bicuspid aortic valve
Teratology of Fallot

Question 4

Describe the triad of infective endocarditis pathophysiology

Answer 4

Endothelial damage - may be sue to sheer stress forces
Platelet adhesion
Microbial adherence - bacteraemia, once bacteria attached to lesion they can proliferate rapidly

Question 5

List some organisms which have specific receptors to fibronectin and allow microbes to adhere to the thrombus at outset

Answer 5

Staphylococcus aureus
Streptococcus viridians - common after dental procedures
Streptococcus pneumonia
HACEK organisms - Haemophilus, Actinobacilus, cardiobacterium, Eikenella, Kingella
Group A, C, G streptococci
Candida albicans

Question 6

List the clinical features of infective endocarditis

Answer 6

Low grade fever
New/changed murmur 
Splenomegaly
Janeway lesions, oslers nodes, petichae, splinter haemorrhages 
Malaise
Fatigue
Weight loss
Myalgia
Cardiac failure - valve destruction

Question 7

List the investigations for IE?

Answer 7

Blood cultures
Echocardiography
Bloods - anaemia, leucocytosis, raised ESR
Urine dipstick - Microscopic haematuria

Question 8

Name the diagnostic criteria for IE

Answer 8

Modified Dukes criteria

Question 9

What must be needed for a diagnosis of IE according to modified dukes criteria?

Answer 9

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

Question 10

List the major criteria of modified dukes criteria

Answer 10

Blood culture

Echo

Question 11

List the minor criteria of modified dukes criteria

Answer 11

Predisposition
Fever
Vascular phenomena 
Immunological phenomenon 
Microbiological evidence
Echo findings

Question 12

Describe the management of IE

Answer 12

Medical
Surgical - depends on the valves
Empirical IV antibiotics and then refine when sensitives known

Question 13

Is routine antibiotic prophylaxis given to at risk patients before dental procedures?

Answer 13

No