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
What are some symptoms of mitral stenosis?
- SOB and oedema when severe
What are some signs of mitral stenosis?
- mitral facies (facial flushing due to low CO)
- tapping apex
- AF is common
- RHF: ankle oedema, hepatomegaly, raised JVP
What is the natural hx of mitral stenosis?
LA dilatation -> pulmonary congestion and oedema -> chronic hypoxia -> pulmonary vasoconstriction -> pulmonary htn -> right heart failure
- note that LA dilation may also cause AF -> the poorly contracting LA will result in stasis of blood and development of thrombi -> thromboembolic events
What are some causes of mitral regurgitation?
- mitral valve prolapse is most common (aka myxomatous valve degeneration)
- functional: LV dilatation
- annular calcification
- RHD
- IE
- ruptured chordae tendinae/ papillary muscle
- connective tissue disorders
- cardiomyopathy
- congenital
- appetite suppresants (e.g. phentermine)
What are some symptoms of mitral regurg?
- even severe MR is asymptomatic unless decompensation occurs
- > symptoms of HF
- SOB, ankle oedema, fatigue, palpitations
What are some signs of MR?
- murmur: pansystolic murmur best heard over the apex and may radiate to axilla
What are some causes of tricuspid regurg?
- relatively common finding in healthy people
- functional (dilate RV)
- RHD
- IE (suspect if IVDU)
- carcinoid syndrome
- congenital
- drugs
What are some symptoms of TR?
- fatigue
- hepatic pain on exertion
- ascites
- oedema
What are some signs of TR?
- JVP: giant V waves with prominent Y descent
- murmur: pansystolic murmur best heard over the lower left sternal edge in inspiration
- pulsatile hepatomegaly, ascites, jaundice
What does a fever + new murmur equal?
- infective endocarditis until proven otherwise
What are some causes of IE?
- S. viridans
- enterococci
- S. aureus (most common acute cause)
- diptheroids
- others
What are some important hx causes to ask when suspecting IE?
- recent hx of medical, surgical or dental procedures
- any prosthetics (valves, joints)
- any IV drug use
- any pre-existing cardiac lesions
- any recent bacterial infections
What are some signs/symptoms of IE?
- fevers, rigors, night sweats, malaise, weight loss, splenomegaly, clubbing
What are some examination findings of IE?
- new murmur or signs of HF
- petechiae
- splinter haemorrhages
- Janeway lesions
- Osler’s nodes
- Roth spots
- embolic phenomena
What are investigations that should be performed for suspected IE?
- blood cultures (3 sets at different times from different locations)
- blood tests: FBE, CRP
- urinalysis (look for haematuria)
- CXR
- ECG
- Echo or TOE (looking for vegetations)
What is the difference between mitral regurgitation and mitral prolapse?
In mitral regurg the valve does not close properly, in mitral prolapse, a part of the valve bulges back into the atrium during ventricular systole
What are the features of a mitral valve prolapse murmur?
Auscultation: midsystolic click followed by a middle-late systolic murmur (“blowing”)
What is the character of the hypertrophic cardiomyopathy murmur?
- heard best at apex and lower left sternal edge
- pansystolic at apex and late systolic at lower left sternal edge
- louder with valsalva and softer with squatting
- may hear S4, have a double-apex beat and jerky carotid pulse
