Valvular Disease Flashcards
What are the four types of valvular disease?
mitral stenosis
mitral regurgitation
Aortic stenosis
Aortic regurgitation
What is the main cause for mitral stenosis
rheumatic heart disease
Describe the sequences of patho physiology of mitral stenosis.
Valve decreases in size-MV orifice
What are the clinical signs of mitral stenosis ?
¥ Dyspnoea (SOB): mild exertional to pulmonary oedema
¥ Haemoptisis: rupture of thin-walled veins
¥ Systemic embolisation: Left Atria and Left Atria Appendage enlargement – which can cause a stroke
¥ IE – infected endocarditis
¥ Chest pain
Hoarseness (compression of the L recurrent laryngeal nerve
Clinical examination for mitral stenosis.
¥ Mitral facies – redness of the checks and nose ¥ Pulse – normal (no volume overload) ¥ JVP – prominent a wave ¥ Tapping apex beat and diastolic thrill ¥ RV heave ¥ Murmur on auscultation
What four investigations should be done for mitral stenosis?
- ECG
- CXR
- Echocardiography - Thickening and scarring of the leaflets, Fusion of the commissures
- Cardiac magnetic resonance
what is the treatment for mitral stenosis ?
Nothing should be done until the stenosis is severe.
¥ Diuretics and restriction of Na intake
¥ AF: SR restoration or ventricular rate control
¥ Anticoagulation: all those with AF, debatable in SR
Intervention treatment:
¥ Valvotomy (balloon vs surgical)
¥ MVR
What are the causes of mitral regurgitation?
¥ Rheumatic Heart Disease – strephtococcal infection (sore throat) = leading cause
¥ Mitral valve prolapse (MVP) – bulges into atrium
¥ IE – infected endocarditis
¥ Degenerative – genetic
¥ Functional Mitral Regurgitation due to LV and annular (ring around valve) dilatation
When the annular enlarged the regurgitant volume increases with MR. The enlargement is dependant on three things. What are they?
preload
after load
LV contractibility
The left ventricle has to pump harder as the preload is less as blood is flowing back into the left atrium instead of out the aorta.
Compare the differences of acute and chronic mitral regurgitation.
ACUTE - Decreased = ESV and wall tension
CHRONIC - Increased = EDV, Normal = ESV, LVH develops
What are the clinical signs of acute and chronic mitral regurgitation?
Acute MR (valve perforation(hole), chordal/pap muscle) - sudden
¥ Breathlessness: pulm oedema, cardiogenick shock
¥ Rapid, sudden volume overload, sudden snapping of pap muscle for example
Chronic MR:
¥ Fatigue, exhaustion (low CO), Right heart failure, SOB
¥ Dyspnoea or palpitations due to Afib
¥ Over years
What should be found on clinical examination with MR?
¥ Pulse – normal or reduced in heart failure
¥ JVP – prominent if RH failure present
¥ Brisk and hyperdynamic apex beat
¥ RV heave
¥ Murmur - Holosystolic, blowing, loud at apex, radiating to the axilla
What are the three investigations that should be done for mitral regurgitation?
¥ ECG: o LA enlargement (P>0.12 sec, tall), o RVH (prominent R wave in R precordial leads) ¥ CXR: o cardiomegaly, o LA enlargement, o calcification of mitral annulus ¥ Cardiac catheterisation: o LV angiography – obsolete ¥ Echocardiography o LV dimensions
Treatment for mitral regurgitation?
¥ Acute MR: preload and afterload reduction may be life-saving (sodium nitroprusside, dobutamine, IABP- vasodilators)
¥ Chronic MR: lack of evidence that any therapy is beneficial for haemodynamic improvement, LV function preservation – wait till severe
Interventional treatment – only if regurgitation is severe
¥ Mitral valve apparatus repair
¥ Mitral valve replacement
LA compliance may be increased or decreased with MR.
What are the effects of increased and decreased compliance?
Reduced - marked pressure rise, - thickening of atrial myocardium, - increase in PVR - remodeling of the pulmonary vasculature with PHT Increased – - marked volume enlargement, - lesser changes in pulmonary vasculature - develop AF
What are the three causes of aortic stenosis?
¥ Degenerative - linked to atherosclerosis, a slow inflammatory process resulting in thickening and calcification of the cusps from base to free margins
¥ Rheumatic - Adhesion, fusion of the commissures and retraction and stiffening of the free cusp margins
¥ Bicuspid – born with two cusps – prone to becoming leaky/narrow
What is the normal and stenosed diameters of the aorta?
normal = 3-4cm
stenosis =
What is the patho physiology of aortic stenosis?
- Increased LV systolic pressure
- Severe concentric hypertrophy and LVM (mass)
- Increased LVEDP (Left atrial p increases, PHT)
- Increased O2 demand
- Myocardial ischaemia
- LV failure
what are the symptoms of aortic stenosis?
¥ Long asymptomatic phase- can go decades without symptoms
¥ However, when the patient gets symptoms the survival curve is very dramatic and sudden death rate is very high.
¥ Cardinal Symptoms
Ð Chest pain (angina)
Ð Syncope/Dizziness (exertional pre-syncope)
Ð Breathlessness on exertion
Ð Heart failure
What would be found on clinical examination for aortic stenosis?
¥ Pulse – small volume and slowly rising
¥ JVP – prominent if RH failure present, low BP
¥ Vigurous and sustained apex beat
¥ RV heave
¥ Murmur = Late peaking, loud at the base, harsh, radiating to the carotids – easiest murmur to hear
What are the three investigations used for aortic stenosis/
ECG (LV strain) CXR Echocardiography o Demonstrates the AV cusp mobility o LV function and hypertrophy o Doppler haemodynamic assessment of pressure gradient and AVA
Treatment for aortic stenosis?
Very limited
Interventional treatment
¥ Aortic valve replacement or repair
What are the main causes for aortic regurgitation regarding the aorta and the leaflets?
Aorta
Ð Dilated aorta (Marfans, hypertension)
Ð Connective tissue disorders – aorta becomes enlarged which pulls the leaflets apart and causes the valve to be more leaky.
Leaflets Ð Bicuspid aortic valve Ð Rheumatic heart disease Ð Endocarditis Ð Myxomatous degeneration
What is the patho physiology for aortic regurgitation?
- LV accommodates both SV and RegVol (volume overload)
- Increased LV-EDV and LV systolic pressure
- LV hypertrophy as LV having to pump harder to expel more blood and LV dilatation
- Increased demand for O2
- Myocardial ischaemia
- LV failure
Symptoms of aortic regurgitation
¥ Chronic AR:
Ð Long asymptomatic phase
Ð Exertional breathlesness
¥ Acute AR:
Ð Poorly tolerated as wall tension cannot acutely adapt
What would you find on clinical examination of aortic regurgitation?
¥ Pulse – large volume and collapsing (Corrigan sign)
¥ Wide pulse pressure – eg. 200/30 BP
¥ Hyperdynamic, displaced apex beat
¥ Murmur = Early diastolic, descrescendo, soft murmur
What are the three investigations that would be done for aortic regurgitation?
¥ ECG: ST/T changes (LV strain), LAD
¥ CXR: cardiomegaly in chronic AR
¥ Echocardiography
o Demonstrates the AV cusp anatomy (thickening, prolapsing, number of cusps, vegetations)
o LV function, dilatation and hypertrophy
o Doppler haemodynamic assessment of regurgitant flow
What is the treatment of aortic regurgitation ?
¥ Vasodilator therapy shown to delay the timing for surgical intervention
Interventional treatment
¥ Aortic valve replacement or repair