Valvular heart disease Flashcards
What causes Rheumatic heart disease?
- immune response to M protein of S.pyogenes 2-3 weeks post-infection (Scarlet fever, pharyngitis)
Which group of people is rheumatic heart disease most common?
- children (6-15 yrs) of developing countries and NT
What are the clinical features of rheumatic heart disease?
Hint: major and minor criteria
Major criteria: “CASES”
- Carditis: tachy, murmur, pericardial rub, CCF, cardiomegaly, conduction defects
- Arthritis: migratory polyarthritis which affects larger joints
- Subcutaneous nodules
- Erythema marginatum
- Sydenham’s chorea
Minor criteria:
- fever
- raised ESR/CRP
- arthralgia
- prolonged PR interval
- previous rheumatic fever
What is the management for RHD?
- bed rest until CRP normal for 2 weeks
- benzyl penicillin IV then PO for 10 days
- analgesia for carditis and arthritis
What are the cardiac sequelae for RHD?
- mitral (70%)
- aortic (40%)
- tricuspid (10%)
- pulmonary (2%)
- incompetent lesions develop during the attack and stenotic lesions develop years later
Do incompetent lesions develop during the attack or years later in RHD?
- During the attack
- stenotic lesions develop years later
How long does an attack of rheumatic fever last?
- 3 months on average
In aortic regurgitation:
which chamber is affected?
what kind of load?
what is the effect?
- left ventricle
- volume
- eccentric hypertrophy
In mitral regurgitation:
which chamber is affected?
what kind of load?
what is the effect?
- left ventricle
- volume
- eccentric hypertrophy
In aortic stenosis:
which chamber is affected?
what kind of load?
what is the effect?
- left ventricle
- pressure
- concentric hypertrophy
In mitral stenosis:
which chamber is affected?
what kind of load?
what is the effect?
- left atrium
- pressure
- left atrial dilatation
With stenotic valve lesions when is it best to operate?
When symptoms appear, the hypertrophy will regress after surgery
With incompetent valve lesions when is it best to operate?
Before symptoms, as they coincide with irreversible changes in the left ventricle
What are some causes of aortic stenosis?
- calcific change
- congenital aortic stenosis/ born with bicuspid aortic valve (predisposes to stenosis)
- rheumatic fever
What are some symptoms of AS?
- asymptomatic while compensated
- SOB on exertion, angina and syncope
What are the signs of AS?
- murmur: ejection systolic crescendo-decrescendo murmur best heard over the upper right sternal edge
- may radiate to carotids
- carotid pulse has a slow upstroke (plateau)
- thrill over upper right sternal edge
- heaving apex
What gradient and valve area are considered severe AS on echo?
- gradient >50mmHg
- valve area <0.7cm2
What are some causes of aortic regurgitation?
- acute: IE, ascending aortic dissection, trauma
- chronic: congenital, connective tissue disorders, RHD, Takayasu arteritis, RA, SLE, syphilis
What is the pathophys of aortic regurgitation?
Due to inadequate closure of the aortic valve leaflets from:
- damaged valve leaflets
or
- dilation of the aortic root or ascending aorta
- portion of SV leaks back into the LV -> increased LV ESV -> increased LV EDV -> hypertrophy and chamber enlargement -> raised SV to maintain CO initially
What are some symptoms of AR?
- may remain asymptomatic for decades
- might have symptoms relating to large heart mass - palpitations, a sense of pounding in chest
- if decompensation: symptoms of left sided heart failure
What are some signs of AR?
- relate to high volume pulse -> collapsing pulse, wide pulse pressure
- murmur: early diastolic
Compare the pulse felt in AS with that felt in AR
Aortic stenosis: plateau (slow upstroke)
Aortic regurg: collapsing (wide pulse pressure)
What are the indicators of LV decompensation?
- increasing size
- decreasing function
What are some causes of mitral stenosis?
- most common cause is RHD (espec in women)
- others include congenital, fibrosis and calcification, carcinoid tumours
