Valvular Disorders

RHD = Rh heart disease

IE = Infective endocarditis

NBTE = Nonbacterial thrombotic endocarditis

sterile
aortic valve > mitral valve > tricuspid valve > pulmonary valve
- ie in order of pressure gradients
e.g. hyper coag [states inc malignancy esp mucin producing adenocarcinomas like pancreatic, gastric; SLE...] and trauma)

LSE = Libman-Sacks Endocarditis (in 10% SLE)

Acute Rheumatic Fever

Systemic complication of pharyngitis
Due to group A β-haemolytic streptococci
- Streptococcus pyogenes
- Lancefield A
- Gram +ve
- M protein - virulence - and mimicry
- T antigen - surface
- erythrogenic toxin
- Other complications
- - toxic shock syndrome
  - NB diff strain causes scarlet fever than causes RhF
  - Rheumatic fever
  - Post-streptococcal glomerulonephritis

2-3 weeks after pharyngitis/tonsilitis
M protein
- Causes molecular mimicry
Jones Criteria to Dx Rh Fever
- Evidence of prior strep pyogenes infection
  - anti-DNA
  - Anti-Streptolysin -O titre
  - anti-DNAse B titre
- Minor criteria
  - Fever
  - Elevated ESR
  - Prolonged PR interval
- Major
  - J - joints - migratory polyarthritis - pain, swelling of one large joint, resolves, moves to other large joint
  - O - pancarditis - endo, peri [fibrinous] and myocarditis
    - Endocarditis - causes vegetations especially on valves, especially on mitral - poss also aortic as well
      - Thus mitral valve regurg, maybe aortic too
    - Myocarditis - Aschoff bodies
      - Chronic inflammation with giant cells, essentially a granuloma
      - Fibrinoid - degenarated collagen
      - High risk of death in acute phase
      - Anitschkow cells
        Macrophages with thin hairy nucleus
      - Pericarditis - friction rub
      - If survive acute phase, progress to chronic
        Repeat strep pyogenes infection may cause acute relapse
        Inc risk for chronic Rh valvular disease
  - N - nodules - subcutaneous
  - E - erythema marginatum - redder at margins
  - S - Sydenham's Chorea
Chronic disease almost always involves mitral valve
- Thicken chordae tendineae, cusps
  - Fish mouth appearance
- Occasionally aortic too - fusion of commissures
  - Causes stenosis
  - If have this, will undoubtedly also have mitral involvement
  - Can see best on the top and left of this pic:
- Other valves rarely involved
- Complication of damaged valve = endocarditis

Aortic Stenosis

Opening should be 4cm2 - when stenosed, less than 1cm2
- Severe:
  - mean gradient >40 mmHg (>45 replace)
  - aortic valve area (AVA) <1 cm2 (replace if <0.6)
  - peak aortic jet velocity >4.0 m/s
Usually due to fibrosis and calcification
- Also poss due to chronic Rh Fever
- - But if don't have mitral disease, then not Rh as always hits mitral first
  - & Don't get commissure fusion in "wear and tear" aortic stenosis
Presents
- Late adult - >50yo
Bicuspid valve inc risk, more rapid progression
- Turner's syndrome
- >50% of pts with coarctation or interruption of the aorta
- William's syndrome (7q) - supravalvular stenosis too
- PDA
- Cystic medial necrosis (AD - not the cystic medial degen in Marfan's!)
Get compensation
- Prolonged, aSx stage
- LV hypetrophies to get past inc resistence
- Ejection systolic click as valve opens
- Crescendo-decrescendo systolic murmur
Complications
- Concentric left ventricular hypertrophy
- Angina, syncope with exercise
- - Limited capacity to increase CO
- Microangiopathic haemolytic anaemia
- - RBCs rutpure when forced passed stenotic valve!
Rx
- Replacement if Sx

Aortic regurgitation

Backflow from aorta to LV during diastole
Due to
- Isolated aortic root dilatation - most common cause
- - "pulls" on valves
  - so open up a bit
  - May be due to syphilitic aneurysm - tree bark aortic root
- Valve damage
- - Infective endocarditis
Presents
- Early, blowing diastolic murmur
- Low diastolic pressure
- - As lose pressure when blood falls back through aortic valve
- Inc systolic
- - as inc SV as more blood regurged back in
- so Widened pulse pressure
- Hyperdynamic circulation
- - Collapsing pulse
  - - Watson's water hammer pulse in upper limb
    - Corrigan's pulse - rapid up and collapse of carotid pulse
  - Pulsating nailbed - Quincke's sign
  - Head nodding - De Musset's sign - Musset nods his mullet
  - 'pistol shot' systolic sound heard over the femoral artery - Traube's sign
  - Uvula pulsation - Muller's sign
  - Retinal vessel pulsation - Becker's sign
  - Diatolic drop> 15mmHg when raise arms
- Volume overload
- - LV dilatation
  - Eccentric hypertrophy
  - - ie doesn't involve entire ventricle, only part
Rx
- valve replacement once get LV impairment

Mitral Valve Prolapse

Ballooning of mitral valve into left atrium during systole
Due to myxoid degeneration of valve - makes floppy
- dermatan sulfate accumulation
? aetiology - get in
- Idiopathic
- Marfan's syndrome
- Ehlers-Danlos Syndrome,
- Polycystic Kidney Disease
- Graves' disease
  - (also main cause of myxoeddema - proteoglycan etc build up!)
- Pectus excavatum
- Pts tend to be lean, low BMI
Presents
- Hear a mid systolic click
- Some regurg, not always
- Most aSx
Complications
- Infective edocarditis
- Arryhthmia
- Severe mitral regurg
- These are rare
Rx
- Valve replacement

Mitral regurgitation

Reflux blood from LV to LA during systole
Usually complication of mitral valve prolapse
Other causes
- LV dilatation - stretch - eg dilated cardiomyopathy
- Infective endocarditis - damage leaflets
- Acute Rh heart disease - vegetations
- Papillary muscle rupture post MI - can't hold leaflets in
Presents
- Holosystolic blowing murmur
- - Louder on squatting - inc peripheral resistance so more "back pressure" through LV and thus mitral valve
  - Expiration - inc blood coming to LV from lungs - so more blood to regurge

Mitral stenosis

Narrowing
Usually chronic Rh valve disease (cf acute causes regurg)
Presents
- Opening snap
- Diastolic mumble
Complication
- Volume overload of LA
- Dilates LA
- Pulmonary congestion - back up pressure from LA to lungs
- - Thus pulm oedema
  - and pulm HTN
  - and capillary haemorrhage so haemosiderin laden macrophages (heart failure cells)
  - and maybe thus cor pulmonale
- Atrial fibrillation
- - due to dilatation of LA
  - mucks up conducting system
  - Get areas of stasis and thus risk of mural thrombosis

Valvular Disorders - Pathoma