Mitral stenosis

Question 1

Define mitral stenosis

Answer 1

Mitral valve narrowing causing obstruction to blood flow from the left atrium to the left ventricle

Question 2

Explain the aetiology/risk factors for mitral stenosis

Answer 2

MAIN CAUSE:
Rheumatic Heart Disease (90% of cases)

Rare causes of mitral stenosis:
Congenital mitral stenosis
SLE
Rheumatoid arthritis
Endocarditis
Atrial myxoma

Question 3

Summarise the epidemiology of mitral stenosis

Answer 3

Incidence is declining because rheumatic fever is becoming more and more rare

Question 4

Recognise the presenting symptoms of mitral stenosis

Answer 4

May be ASYMPTOMATIC
Fatigue
Shortness of breath on exertion
Orthopnoea
Palpitations (related to AF)

Rare symptoms:
Cough
Haemoptysis
Hoarseness caused by compression of left recurrent laryngeal nerve by an enlarged left atrium

Question 5

Recognise the signs of mitral stenosis on physical examination

Answer 5

Peripheral cyanosis
Malar flush
Irregularly irregular pulse (if in AF)
Apex beat undisplaced and tapping
Parasternal heave (due to right ventricular hypertrophy
secondary to pulmonary hypertension)
Loud S1 with opening snap
Mid-diastolic murmur
Evidence of pulmonary oedema on lung auscultation (if
decompensated)

Question 6

Identify appropriate investigations for mitral stenosis

Answer 6

ECG
May be NORMAL
May see p mitrale (broad bifid p wave caused by left atrial hypertrophy)
May see AF
Evidence of right ventricular hypertrophy may be seen
if there is severe pulmonary hypertension

CXR
Left atrial enlargement
Cardiac enlargement
Pulmonary congestion
Mitral valve calcification (occurs in rheumatic cases)

Echocardiography
Assesses functional and structural impairments
Transoesophageal echocardiogram (TOE) gives a better view
Cardiac Catheterisation
Measures severity of heart failure