Valvular heart disease Flashcards
what is the only bicuspid valve?
mitral
how wide is the diameter of the mitral valve?
4-6cm
what is the difference between stenosis and regurgitation?
stenosis is narrowing and regurgitation is leakage
what is the most common aetiology for AS?
rheumatic heart disease (caused by rheumatic fever)
congenital MS (rare) - patient born with it
systemic conditions such as rheumatic arthritis
describe the pathophysiology of Mitral stenosis?
MV orifice decreases (less than 2cm squared), so Atrium to ventricle pressure gradient increases, then left atrium pressure increases so pulmonary venous and capillary pressures increase, so pulmonary venous resistance increases then increase in pulmonary artery pressure.
what brings on tachycarida in patients with MS?
exercise, acute illness, pregnancy, and atrial fibrillation
what are the clinical manifestations of MS?
shortness of breath (dyspnoea) due to mild exertional (SOB on exercise) or pulmonary oedema
haemoptysis - caused by the rupture of the thin-walled veins in pulmonary circulation (due to pressure)
systemic embolization - caused by LA enlargement and stagnant blood flow happens, resulting in clots within then they can go into the systemic circulation and cause stroke ECT
infected valve
chest pain
and hoarse voice (compression of left recurrent laryngeal nerve)
clinical examination signs of MS?
pulse is normal
mitral facies (purple/reddish look on cheeks and nose)
JVP - prominent a wave
tapping apex beat and diastolic thrill due to murmur (5th left intercostal space)
RV heave
what does AS appear as on an ECG and CXR?
taller QRS complex in leads V1 and 2
P wave is greater than 0.12 seconds
LA enlargement
what do we use, in terms of imaging, to diagnose MS?
echocardiography
can see thickening and scarring of the valve leaflets and anterior leaflet moves up in an ‘elbowing’ fashion
look over the recording of this scan
how do we treat mitral stenosis?
diuretics and restriction of sodium intake
AF: sinus rhythm restoration or try restore heart rate if very fast (ventricular rate)
ANTICOAGULATION: all those with AF, so if atria is enlarged anti coagulate
what is the causes of mitral regurgitation?
rheumatic heart disease and infection
mitral valve prolapse
degenerative - degenerates the valve with age
functional MR - due to LV enlarges then annulus enlarges as result
what are the clinical manifestations of MR (acute and chronic)?
acute MR - valve perforation (hole in the valve) and damage to the papillary muscle and breathlessness - pulmonary oedema or cardiogenic shock
chronic MR - fatigue, exhaustion (low CO), right heart failure and dyspnoea or palpitations due to atrial fibrillation
what are the signs of MR on examination?
normal or reduced pulse in heart failure
JVP - prominent if RH failure is present
brisk and hyperdynamic apex beat
RV heave
auscultation: reduced S1 (because valve leaflets cannot find one another), splits at S2 (early AV2, loud PV2) - so in summary, holosystolic, blowing loud at the apex and radiating to axilla
when looking at MR on ECG, what features are prominent?
P wave greater than 0.12 seconds, tall
RVH leads to prominent R wave in right precordial leads
how do we treat MR?
acute MR: preload and afterload (2 determinants of CO) reduction bay be life-saving - should prescribe vasodilators like sodium nitroprusside, And dobutamine to increase heart rate)
in chronic - no therapy so refer them for interventional treatment (such as mitral valve apparatus repair or valve replacement)
what is the most common congenital heart abnormality?
bicuspid aortic stenosis
what are the symptoms of aortic stenosis?
angina
dizziness
breathlessness on exertion
heart failure
clinical examination of aortic stenosis?
pulse - small volume and slowly rising
JVP - prominent if RH failure present , low blood pressure
vigorous and sustained apex beat
RV heave
has a normal S1, S2 less audible
upon CXR, what can be seen on AS?
calcification of AV
what is the medical treatment for AS and when is it given?
aortic valve replacement or repair
only limited to those who develop heart failure
what is aortic regurgitation?
a leaky aortic valve
what are the 2 main streams aortic regurgitation can be divided into?
aortic diseases - dilated aorta (Marfan’s, hypertension), connective tissue disorders
leaflets - bicuspid aortic valve, rheumatic heart disease, endocarditis, and myxomatous degeneration
explain the pathophysiology of AR
left ventricle will have accommodates both stroke volume and regurgitate volume, leading to increase in left ventricular end diastolic volume and LV systolic pressure which will result in LV hypertrophy and LV dilation, therefore an increased myocardial oxygen consumption, resulting in ischaemia and then LV failure
what is the signs of aortic regurgitation upon clinical examination?
large vol. and collapsing pulse
side pulse pressure (means systolic high, and diastolic low because a lot of ejected volume comes back into ventricle from aorta)
hyperdynamic, displaced apex beat
early diastolic, decrescendo soft murmur (very hard to listen to)
what will aortic regurgitation appear as on ECG and CXR?
ST/T wave changes (LV strain), and left axis deviation
CXR: cardiomegaly (mostly in chronic AR)
