CVPR Week 9: Acquired Heart disease Flashcards
Objectives
Rheumatic fever description
Rheumatic heart disease
damage to the valves secondary to ARF can become a chronic condition leading to congestive heart failure, strokes, endocarditis and death
ARF AKA
Acute Rheumatic fever
Rheumatic fever and heart disease
significant public health concerns around the world and despite decreasing incidence there is still a significant disease burden especially in developing nations
Describe the epidemiology of rheumatic fever and rheumatic heart disease
significant public health concerns around the world and despite decreasing incidence there is still a significant disease burden especially in developing nations
Describe the epidemiology of rheumatic fever and rheumatic heart disease
Acute rheumatic fever pathogenesis
a consequence of anti-strep antibodies cross-reacting with group A carbohydrate (human heart valves, M-protein (heart-muscle), protoplast membrane (sarcolemma)
Acute rheumatic fever clinical presentation
- 30% subclinical
- presentation 1-3 weeks post strep
- case fatality rate is 2-3 %
Rheumatic fever/Rheumatic heart disease age of onset
Group A Streptococcus (GAS) pharyngitis occurs most commonly between 5-15 years of age
Rheumatic fever/Rheumatic heart disease precipitating infection
GAS pharyngitis and not skin infections (impetigo)
Rheumatic fever/Rheumatic heart disease strains
Strains that cause RF & RHD are based on type of M-protein
Why does RF & RHD occur in response to an infection?
- Because streptococcal antigens mimic normal human tissue antigens (molecular mimicry)
- so this leads to abnormal autoimmune humoral and cellular responses
Describe the immune response in RF/RHD
Rheumatogenic strains/encapsulated mucoid M strains are resistant to phagocytosis so they are particularly immunogenic and produce antibodies against epitopes
similar epitopes in sarcolemmal membranes and valve glycoproteins
Describe the path to RF/RHD
Dx of Acute Rheumatic Fever
Jones criteria
Jones Criteria Dx what
Acute Rheumatic fever
Describe the Jones criteria for Dx
2 major criteria or 1 major and 2 minor criteria - PLUS
- preceding documented strep infection by throat culture or antibody (antistreptolysin (ASO titer) or Antideoxyribonuclease B titer (anti-DNase B titer)
What are the major criteria of the Jones Criteria
- Polyarthritis
- Carditis
- Chorea
- Subcutaneous nodules
- Erythema Marginatum
What are the minor criteria of the Jones Criteria
- Arthralgia
- Prolonged PR interval on ECG
- Fever
- Elevated acute phase reactants
- History of rheumatic fever
What are the skin findings in RF
- Erythemia marginatum
- subcutaneous nodules
Describe erythema marginatum
- <5% of RF patients
- Bright pink, serpiginous borders and central clearing
- Non-pruritic, non-painful and blanch with pressure
- located on trunk or proximal extremities
Describe subcutaneous nodules
- 0-10% of RF cases (not pathognomic)
- 0.5 - 2.0 cm round, firm, movable, non-tender nodules
- Usually occur over extensor, surfaces of joints, scalp or spinous processes of back
- last 1-2 weeks
What is Sydenham Chorea?
involuntary purposeless movements, muscular incoordination/weakness and emotional lability
How often does Syndenham chorea occure in RF?
10-30% of cases of RF
Why does Sydenham Chorea occur
occur due to inflammation in basal ganglia, cerebral cortex and cerebellum
Latency period of RF with chorea
longer latency period from GAS infection (acute phase-reactants and antibodies often not elevated)
How long does Sydenham Chorea last
lasts anywhere from 1-2 weeks to 2-3 years
What % of group A beta haemolytic streptococcal infection progress to develop acute rheumatic fever
0.3 - 30% of untreated develop acute rheumatic fever
Prevalence of Carditis in acute rheumatic fever
30-70% of cases
Severe carditis and heart failure occurs in 13-64% of RF cases
Carditis onset in RF
most often occurs within 2 weeks of acute illness
What is pancarditis?
is the inflammation of the entire heart: the epicardium, the myocardium and the endocardium.
What is endocarditis?
is an infection of the endocardium, which is the inner lining of your heart chambers and heart valves.Endocarditis generally occurs when bacteria, fungi or other germs from another part of your body, such as your mouth, spread through your bloodstream and attach to damaged areas in your heart
What is myocarditis?
is an inflammation of the heart muscle (myocardium). Myocarditis can affect your heart muscle and your heart’s electrical system, reducing your heart’s ability to pump and causing rapid or abnormal heart rhythms (arrhythmias)
What is pericarditis?
refers to inflammation of the pericardium, two thin layers of a sac-like tissue that surround the heart, hold it in place and help it work. A small amount of fluid keeps the layers separate so that there’s no friction between them.
Describe acute rheumatic carditis
Clinical features of acute rheumatic fever with carditis
- New or changing murmur
- or Silent carditis
- Tachycardia out of proportion to fever
- congestive heart failure
- Pericarditis
Heart murmurs of acute rheumatic fever with carditis
- Apical holosystolic murmur, high-pitched, blowing, with radiation to the axilla - Acute mitral regurgitation
- Apical diastolic murmur - relative mitral stenosis due to large volume of regurgitant flow
- Soft crescendo-decrescendo murmur of aortic insufficiency - acute aortic insufficiency
- Silent carditis - which is only detected on echo imaging
How is silent carditis detected?
detected only on echo imaging
What are the features of congestive heart failure?
- increased JVD
- Crackles
- Hepatomegaly
- Crackles
Features of pericarditis
pericardial friction rub
muffled heart sounds
paradoxical pulse (exaggerated fall in the pulse on inspiration)
Rheumatic heart disease valves effected
- most commonly involves the mitral and then the aortic valve
- but all 4 valves can be affected