Valvular Heart disease Flashcards
What is valvular heart disease?
- Valvular heart disease is the damage to/defect in one of the heart valves
- A stenotic valve ( narrowing) decreases filling of blood in the chamber
- Incompetent valve( widening) valve allows blood to leak back into the chamber it previously exited.
What is mitral stenosis?
-stenosis of the mitral valve which restricts blood flow into the left ventricle
Causes of mitral stenosis
- rheumatic heart disease/fever
- congenital MS
- systemic conditions ( SLE, RA)
Describe the pathophysiology of mitral stenosis
- MV orifice is <2cm2 ( normal is 4-6cm2)
- this increases the A-V pressure gradient
- LA pressure increases in order to overcome the increased A-Vp gradient
- eventually increased BV in LA +backflow of blood from LA>pulmonary veins occur. This causes pulmonary venous and capillary pressures to increase. > pulmonary oedema(maybe)
- PVR +PaP increases and PHT develops
- LA dilation ( due to excess blood in LA > AF as pacemaker cells stretched > stagnant blood) TR and PRea increases
- RH hypertrophy to overcome the pulmonary pressure > RS heart failure
Mitral stenosis severity dependent on?
trans valvular pressure gradient
- trans valvular flow rate (CO + HR)
- tachycardia ( excercise, AI, pregnancy, AF)
Clinical symptoms of mitral stenosis
- dypsonea
- haemoptysis: rupture of thin walled veins
- chest pain
- hoarseness( compression of L recurrent laryngeal nerve)
Clinical presentation of mitral stenosis
- Mitral facies
- normal pulse
- JVP ( prominent A wave)
- tapping apex beat + diastolic thrill
- RV heave
Investigations of mitral stenosis
- ECG catheterisation useless but will show P wave more prominent.
- CXR ( LA enlargement)
- Imaging: ECHO ( thickening and scarring of the leaflets + may show fusion of commissures/valves),
- Cardiac magnetic resonance
Medical treatment of mitral stenosis
- Diuretics and restriction of Na+ intake
- AF:Sinus rythm restoration/ventricular rate control
- anticoagulation; all those with AF debateable in SR
Intravenal treatment
- valvotomy ( balloon vs surgical)
- MVR
Causes of mitral regurgitation
- rheumatic heart disease/fever
- mitral valve prolapse( failure of CT/PM)
- IE
- degenerative with age
- functional MR due to LV and annular dilation
Pathology of mitral regurgiation
Mitral regurgitation is leakage of blood backward through the mitral valve each time the left ventricle contracts.
Pathophysiology of mitral regurgitation
- LA compliance is reduced,
- hypertrophy of LA
- increase in PVR + remodelling of pulmonary vasculature with PHT
- can also devvelop AF
Clinical symptoms of mitral regurgitation
Acute MR
-breathlessness: pulmonary oedema, cardiogenick shock
Chronic MR
-fatigue, exhaustion, low CO, right heart failure, dypsonea, palpitations(due to AFib)
Clinical examination of mitral regurgitation
- pulse ( normal/reduced in HF)
- JVP ( prominent if RH failure present)
- brisk and hyperdynamic apex breat
- RV heave
- asucultation ( reduced S1. split S2: ; click due to the leaflet folding into atrium and being stopped by the CT ; loud at apex, holysystolic, radiating to axilla
Investigations of mitral regurgitation
ECG: LA enlargement ( tall), RVH ( prominent R wave in R preccordial leads)
CXR: cardiomegaly, LA enlargement, calcification of mitral annulus
Cardiac cathetirsation; LV angiography ( obsolete)
Imaging: echocardiography( LV dimensions. Cause of MR: leaflet dysfunction CTae, pap muscles, annular disease)
-severity of MR and pap?
T
??-.???Accurate cardiac volumes
Volumetric determination of Reg Vol
Medical treatment on MR
Acute MR
-preload and afterload reduction ( sodium nitroprusside, dobutamine, IABP)
Chronic MR
-no therapy beneficial
Interventional treatment
- mitral valve apparatus repair
- mitral valve replacement
State the normal aortic valve area (AVA) + the aortic stenosis area
Normal:3-4cm2
Stenosis AVA: 1.5-2cm2
Causes of aortic stenosis
Rheumatic + degenerative
Rhemuatic
- adhesion, fusion of the commissures and retraction + stiffeninf of free cusp margins
Degenerative
-linked to atherosclerosis; slow inflammatory process resulting in thickening and calcification of cusps from base to free margins
Mechanism of of aortic stenosis
Increased
Symptoms of aortic stenosis
- asymptomatic
- cardinal symptoms include chest pain(angina), syncope/dizziness, breathlessness on exertion, heart failure
Clinical examination of aortic stenosis
Pulse- small volume + slowely rising
JVP- prominent if RH failure present, low BP
-vigorous apex beat
-RV heave
-auscultation ( late peaking, loud at base +r adiating to carotids)
Investigations of aortic stenosis
- ECG: LVH voltage criteria, ST/T changes, (LV strain)
- CXR ( calcification of AV)
- cardiac catheterisation: peak LV-peak aortic gradient ( obsolete)
- Imaging: CMR, Echocardiography ( shpws AV cusp mobility, function of LV + hypertrophy)
Medical treatment of aortic stenosis
Interventional treatment
-AVR(surgically/percutaneously/repair
Causes of aortic regurgitation
- dilated aorta ( hypertension)
- connective tissue disorders (myoxmatous degeneration, marfan’s)
- bicuspid aortic valve
- rheumatic HD
- endocarditis
Pathophysiology of aortic regurgitation
- LV accomodates both SV and RegVol
- increased LVEDV + LV systolic pressure
- LV hypertrophy + LV dilation
- increased MMVO2
- myocardial isachemia
- LV failure
Symptoms of aortic regurgitation
Chronic
- long asymptomatic phase
- dypsonea upon exertion
Acute
-poorly tolerated as wall tension cannot acutely adapt
Clinical presentation of aortic regurgitation
- pulse ( large volume + colapsing) = corrigan sign
- wide pulse pressure
- hyperdynamic, displaced apex beat
- normal S1..?
Aortic regurgitation investigation
- CXR: cardiomegaly (bovine heart) in chronic AR
- cardiac cathetiisation ( obsolete, aortogram
- Imaging; ECG: ST/T changes (LV strain, LAD), echocardiography(shows AV cusp thickening, prolapsing, number of cusps, vegetations)
- LV function, dilation and hypertrophy, doppler haemodynamic
Medical treatment of aortic regurgitation
- vasodilator therapy to delay timing for surgical intervention
- Interventional treatment; AVR/repair
