Valvular Heart Disease Flashcards
What are the main types of valvular heart disease?
Aortic Stenosis
Mitral Regurgitation
Mitral Stenosis
Aortic Regurgitation
What can cause mitral stenosis?
Rheumatic heart disease
Congenital mitral stenosis
Systemic conditions e.g. systemic lupus erythematous, rheumatoid arthrtitis
What is the criteria for mitral stenosis? And what are the physiological repercussions?
Mitral valve orifice <2cm squared
AV pressure gradient increases
LA pressure increases
Pulmonary venous and capillary venous pressure increases
Pulmonary VR increases
Pulmonary artery pressure increases and pulmonary hypertension develops
RH dilatation with tricuspid and pulmonary regurgitation
What are some clinical manifestation/symptoms of mitral stenosis?
SOB - mild exertional to pulmonary oedema
Haemoptysis due to rupture of thin-walled veins
Systemic embolisation - LA and LA appendage enlargement
Infective endocarditis
Chest pain
Hoarseness due to compression of L recurrent laryngeal nerve
Clinical signs of mitral stenosis?
Mitral facies - rosy cheeks, bluish tinge due to cyanosis Normal pulse Prominent A wave in JVP Tapping apex beat and diastolic thrill RV heave Noise bewteen S2 and S1
What investigations might be done in suspected mitral stenosis?
ECG Cardiac catheterisation CXR for LA enlargement Echo - showing thickening and scarring of valve leaflets, fusion of the commissures Cardiac MRI
What are the treatments in mitral stenosis?
Diuretics and restricted sodium intake
Ventricular rate control if AF
Valvotomy (balloon vs surgical)
Valve replacement
What are some causes of mitral regurgitation?
Rheumatic heart disease Mitral valve prolapse Infective endocarditis Degenerative Functional mitral regurgitation due to LV and annular dilatation
What is the pathophysiology of mitral regurgitation?
Effective regurgitant orifice not fixed
- preload
- afterload
- LV contractility
Leads to LV compensation
- acute - end-systolic pressure and ESV decreased, wall tension decreased
- chronic = EDV increased and ESV back to normal, eccentric LVH develops
LA compliance
- reduced - marked pressure rise, thickening of atrial myocardium
- increased - marked volume enlargement
- combination?
Symptoms of mitral regurgitation?
Acute
- SOB from pulmonary oedema or cardiogenic shock
Chronic
- fatigue, exhaustion (low cardiac output), RHF
- SOB or palpitations due to AF
Signs of mitral regurgitation?
Pulse normal or reduced if HF JVP prominent if RHF present Brisk and hyperdynamic apex beat RV heave Auscultation - reduced S1, holosystolic, blowing, loud at apex, radiation to axilla
Investigations done in suspected mitral regurgitation?
ECG for LA enlargement (P>0.12s, tall)
- RVH prominent R wave in precordial leads
Echo
- LV dimensions
- cause of MR (leaflet dysfunction, chordae/pap muscle, annular disease
- severity
Treatment for mitral regurgitation?
Acute
- preload and afterload reduction may be lifesaving (sodium nitroprusside, dobutamine, intra-aortic balloon pump)
Chronic
- lack of evidence that any therapy beneficial
Mitral valve repair or replacement
What are the causes of aortic stenosis?
Degenerative - Linked to atherosclerosis, resulting in thickening and calcification of cusps
Rheumatic - ahdesion, fusion of the commissures and retraction and stiffening of free cusp margins
What are the physiological repercussions of aortic stenosis?
Increased LV systolic pressure Severe concentric hypertrophy, and LV mass Increased LV end-diastolic pressure Increased myocardial O2 consumption - myocardial ischaemia LVF
What are the symptoms of aortic stenosis?
Long asymptomatic phase Cardinal symptoms - Chest pain (angina) - Syncope/dizziness - SOB on exertion - Heart failure
What might you find on examination in aortic stenosis?
Small pulse volume, slowly rising Prominent JVP if RHF present Low BP Vigorous and sustained apex beat RV heave Auscultation - late peaking - loud at base - harsh - radiates to carotids
What investigations might be done in suspected aortic stenosis?
ECG
- LVH, ST/T changes (LV strain)
CXR - calcification of valve
Catheterisation (obsolete)
Echo - demonstrates mobility, LV function, hypertrophy
- doppler haemodynamic assessment of pressure gradient
Cardiac MRI
What is the treatment for aortic stenosis?
Limited to those who develop heart failure
Aortic valve replacement/repair
What might cause aortic regurgitation?
Aortic disroder
- Dilated aorta (Marfan’s, hypertension)
- Connective tissue disorders
Leaflet disorder
- bicuspid instead of tri
- rheumatic heart disease
- endocarditis
- myxomatous degeneration
LV accomodates both SV and regurgitant volume
> increased LV end-diastolic pressure and LV systolic pressure
> LVH and LV dilatation
> increased myocardial O2 demand
> ischaemia
> LVF
Symptoms of aortic regurgitation?
Chronic
- long asymptomatic
- exertional SOB
Acute
- poorly tolerated as wall tension cannot acutely adapt
What might be found on examination in aortic regurgitation?
ECG - ST/T changes (LV strain) CXR - cardiomegaly (chronic) Cardiac catheterisation (obsolete)
Echo - demonstrates cusp thickening, prolapse, number, vegetation
- LV function, dilatation and hypertrophy
- doppler haemodynamic assessment
Cardiac MRI
What treatment might be given in aortic regurgitation?
Vasodilator therapy shown to delay the timing for surgical intervention
Aortic valve replacement/repair
