Heart Disorders 2

Question 1

What is Acute Rheumatic Fever?

Answer 1

an acute, immunologically mediated, multi-system inflammatory disease

Question 2

what is rheumatic heart disease?

Answer 2

valvular disease resulting from chronic valve damage as a result of acute rheumatic fever

aka rheumatic valve disease

Question 3

what is the difference between rheumatic fever and rheumatic heart disease

Answer 3

rheumatic fever is an inflammatory disease

rheumatic heart disease is a result of rheumatic fever, leading to chronic valve damage

Question 4

aetiology of rheumatic fever

Answer 4

commonly from group A streptococcal pharyngitis

Question 5

pathogenesis of rheumatic fever

Answer 5

• a hypersensitive response - antibody and T cell
• antibody response against M proteins of streptococci
• CD4 + T cells specific to streptococcal peptides

Question 6

what are the key clinical features of rheumatic fever (5)

Answer 6

• migratory polyarthritis of the large joints
• pancarditis
• skin lesions
• subcutaneous nodules
• CNS - cause Sydenham chorea = involuntary movements
• 10 days-6 weeks post infection

Question 7

what is migratory polyarthiritis?

Answer 7

one large joint becomes painful and swollen for a period of days then subsides
- happens to another large joint
- repeats

Question 8

what is Pancarditis or acute rheumatic carditis?

Answer 8

affecting all three layers of the heart
- can cause cardiac dilation or heart failure

Question 9

what is acute rheumatic carditis? what is affected?

Answer 9

when acute rheumatic fever affects the heart

• can affect the three layers of the heart
  = pericardium
  = myocardium
  = endocardium

Question 10

what are the 3 layers of the heart.

Answer 10

pericardium
myocardium
endocardium

Question 11

with the 3 layers of the heart, what can be a result of acute rheumatic carditis?

Answer 11

pericardium = pericarditis

myocardium = myocarditis

endocardium = endocarditis

Question 12

what is a characteristic feature of myocarditis?

Answer 12

Aschoff bodies - clumps of macrophages recruited into the area of muscle damage due to autoimmune response

Question 13

where can Aschoff bodies be found?

Answer 13

in all three cell layers of the heart
= pancarditis

Question 14

what is the diagnostic criteria of rheumatic fever

Answer 14

using the Jones Criteria
- must have evidence of group A strep infection

patient symptoms
- 2 of the major criteria or
- one major and 2 minor

Question 15

what comes under major diagnostic criteria for acute rheumatic fever? (5)

Answer 15

carditis
polyarthritis
chorea - abnormal movements
erythema marginatum
subcutaneous nodules

Question 16

what comes under minor diagnostic criteria for acute rheumatic fever? (5)

Answer 16

fever
arthralgia
previous rheumatic fever or rheumatic heart disease
acute phase reactions
prolonged PR interval

Question 17

pathogenesis of rheumatic heart disease (6)

Answer 17

• cardiac hypertrophy
• cardiac dilation
• heart failure
• arrhythmias
• veruccae aka vegetations
• mitral stenosis

Question 18

what is mitral stenosis?

Answer 18

narrowing of the mitral valve, found on the left side

Question 19

what is the most likely cause of mitral stenosis?

Answer 19

rheumatic heart disease

Question 20

what are veruccae? - rheumatic heart disease

Answer 20

nodules found in areas of valve damage

Question 21

what valves are involved in rheumatic heart disease?

Answer 21

mostly only mitral valve
25% aortic valve - usually wear and tear
tricuspid/pulomonary valves are uncommon

Question 22

what are the key clinical features of rheumatic heart disease (2)

Answer 22

-permanent and cumulative valve damage
- mitral stenosis - looking like a fish mouth or buttonhole

Question 23

what is the diagnostic criteria of rheumatic heart disease

Answer 23

relies on the Jones Criteria

Question 24

what is endocarditis? how does it usually present?

Answer 24

inflammation of the endocardium
- usually get vegetation lesions on the valve

Question 25

what are the 2 forms of endocarditis?

Answer 25

infective endocarditis
non-infective endocarditis

Question 26

define infective endocarditis

Answer 26

a clinically serious infection

• a microbe colonises or invades the heart valves or heart chamber

Question 27

what are the two types of infective endocarditis?

Answer 27

acute infective endocarditis = the worse one

sub-acute infective endocarditis

Question 28

what is the cause and 3 effects of acute infective endocarditis?

Answer 28

highly virulent organism

necrotising, ulcerative, destructive lesions

Question 29

how is acute infective endocarditis treated?

Answer 29

its difficult to cure

• antibiotics and surgery
• death is frequent

Question 30

what is the cause of subacute infective endocarditis? how it is treated?

Answer 30

lower virulent organisms
less destructive
cured with long-term antibiotics

Question 31

what are the risk factors for infective endocarditis?

4 high risk factors
5 mid risks
1 low risk

Answer 31

high risk
- artificial heart valves
- prior episodes
- complex cardiac defects
- surgically constructed shunts

mod risk
- septal defects
- hypertrophic cardiomyopathy
- valvular dysfunction
- MVP with mitral regurgitation

low risk
- innocent murmur

• organisms in bloodstream = infection
• cardiac vascular abnormalities = abnormal flow = promotes adherence and growth
• rheumatic heart disease - damages the valves, disrupts blood flow

Question 32

what is polymicrobial infective endocarditis? what is a common risk factor and pathogenesis?

Answer 32

infection due to multiple organisms

predominant risk factor = IV drug use

1/3 die

Question 33

what are the clinical features for infective endocarditis?

Answer 33

can be more than one valve
bulky, crumbles away vegetation
can erode and lead to access = ring abscess
can embolise and be septic - contain large numbers of virulent organisms

fever
non-specific symptoms - loss of weight
murmurs - from new valvular defect or pre-existing abnormality

Question 34

how is infective endocarditis diagnosed?

Answer 34

Duke Criteria

Question 35

what is the pathogenesis of infective endocarditis?

Answer 35

any route of bacteria into blood
- dental abnormalities
- wounds
- IV needles

• streptococcus viridans from the mouth
• staph aureus from the skin
• coagulase-negative staphlococci - usually heart valve
• HACEK group - all commensals in oral cavity = unusual

Question 36

what does it mean that endocarditis is culture negative?

Answer 36

you cannot isolate the causative agent

Question 37

what can be the complications/features of infective endocarditis? FROM JANE

Answer 37

F - fever

• Roth Spots
• retinal haemorrhage in the eye
• Osler’s Nodes
• subcutaneous nodules in the pulp of digits

M - murmurs

• Janeway Lesions - erythematous or haemorrhage non-tender lesions on palms or soles
• Anaemia
• Nail splinter haemorrhgaes
• Emboli (septic)

Question 38

what is the treatment for infective endocarditis?

Answer 38

high concentration of IV antibiotics
4-6 weeks

Question 39

what are the clinical guidelines for treating patients with all above conditions?

Answer 39

there is no clear association with dental procedures

• brushing has more risk than procedures
• antibacterial prophylaxis and chlorhexidine mouthwash are not recommended
• maintain high standard of hygiene

-report any unexplained illness after dental treatment, should be investigated promptly