Mitral Stenosis
Symptoms
- Dyspnoea on exertion (early)
- orthopnoea and PND
- worse with AF
- cough andhaemoptysis (due to bronchitis, pulmonary infarction, pulmonary congestation, bronchial vein rupture)
- Systemic emboli
- Fatigue and cold extremities (late)
- Chest pain - coronary artery embolism?
On examination
- malar flush
- breathlessness
- small volume pulse
- AF
- JVP: large v waves (tricuspid regurge)
- left parasternal heave (RVH) ?pansystolic murmur of tricuspid regurge
- palpable P2 (if pulmonary hypertension) (secondary pulmonary regurge)
- arterial pulses may be absent if embolised
- tapping apex beat (palpable S1)
APICAL MURMUR (radiating to axilla)
presystolic accentuation - (due to atrial contraction if in sinus rhythm)
Mid-diastolic rumble - (longer=tighter stenosis)
Differential diagnosis
- inflow obstruction e.g. hypertrophic cardiomyopathy or left atrial myxoma
- aortic regurgitation
- tricuspid stenosis
Investigations
ECG
- AF/ p mitrale in sinus rhythm
- signs of RVH (dominant R wave in V1 and right axis deviation)
CXR
- left atrial enlargement (double shadow behind the heart)
- pulmonary oedema
- splayed carina
- lateral view - valve calcification?
ECHO
- assess area of mitral valve orifice and gradient across valve
- assess left ventricular function, left atrium size and right sided chambers
Cardiac Catheterisation
- if coronary artery disease suspected
- measure pulmonary capillary wedge pressure
Cause
Usually rheumatic fever
4× as common as mitral regurge
women > men
Stenosis - thickening of cusps and fusion of commissures leads to pressure gradient between left atrium and left ventricle.
as stenosis worsens ventricular filling is impaied, compounded by subvalvular apparatus fibrosis leading to left atrial dilation and hypertrophy, AF and thrombosis
may lead to pulmonary congestion causing pulmonary artery pressure and right heart failure
Management
Anticoagulation - patients with AF
risk of emboli greater with large left atrium or left atrial appendage
Pulmonary congestion - diuretics, digoxin
?ß blocker or verapamil
Surgery
Mitral valvotomy or vlave replacement
If not calcified and leaflets pliable - balloon valvuloplasty
Prophylaxis
Antibiotics before dental and surgical procedures to prevent subacute bacterial endocarditis