Valvular disease - Mitral Stenosis Flashcards
What is mitral stenosis?
https://www.youtube.com/watch?v=nY4aaBezu9o
Mitral stenosis is a narrowing of the mitral valve orifice, usually caused by rheumatic valvulitis producing fusion of the valve commissures and thickening of the valve leaflets.
What are causes of mitral stenosis?
- Rheumatic fever
- Congenital MS
- Systemic disease - SLE, RA
- Malignant Carcinoid
- Mucopolysaccharidoses
What is the normal surface area of the mitral valve?
4-6 cm2
What is classed as severe mitral stenosis?
<1 cm2
What happens to the left atrium in mitral stenosis?
In order that sufficient cardiac output will be maintained, the left atrial pressure increases and left atrial hypertrophy and dilatation occur
Why does pulmonary oedema occur in Mitral Stenosis?
Pulmonary venous, arterial and right heart pressures increase. The increase in pulmonary capillary pressure is followed by the development of pulmonary oedema
What can exacerbate pulmonary oedema in mitral stenosis?
Atral fibrillation
What are symptoms of mitral stenosis?
- Dyspnoea
- Fatigue
- Palpitations
- Chest pain
- Systemic emboli
- Haemoptysis
- Lower limb swelling
Why do individuals get dyspnoea in mitral stenosis?
A combination pulmonary venous hypertension and recurrent bronchitis
What causes palpitations and systemic emboli in mitral stenosis?
AF
Why is AF more likely to occur in mitral stenosis?
Larger left atrium is more predisposed to AF
Why can mitral stenosis cause haemoptysis?
Pulmonary hypertension, which leads to varices in the submucosa of the bronchial walls.
What are signs of mitral stenosis?
- Malar flush (Mitral faces)
- Low-volume pulse
- AF
- Tapping, non-displaced apex
- Loud S1
- Opening snap
- Rumbling diastolic murmur
- Graham Steel murmur
What causes the murmur heard in mitral stenosis?
Diastolic blood flow across a damaged, narrow valve - With the valve narrowed, the blood flow across it in diastole is turbulent and produces the characteristic murmur.
Where is mitral stenosis heard best?
Best heard with the bell of the stethoscope held lightly at the apex with the patient lying on the left side