Aortic Stenosis

Causes:                                       

      

[A] Infants, children, adolescents:

1.      Congenital aortic stenosis.

2.      Congenital subvalvular aortic stenosis.

3.      Congenital supravalvular aortic stenosis.

[B] Young adults to middle aged:

1.      Calcification & fibrosis of cong, bicuspid aortic valve.

2.      Rheumatic aortic stenosis.

[C] Middle aged to elderly:

1.      Senile degenerative aortic stenosis.

2.      Calcification of bicuspid valve.

3.      Rheumatic aortic stenosis.

Clinical features:

Symptoms:

1.      Asymptomatic (mild or moderate aortic stenosis)

2.      Exertional dyspnoea due to LVF.

3.      Angina.

4.      Exertional syncope.

5.      Sudden death.

6.      Episodes of acute pulmonary oedema.

Signs:

1.      Pulse: Slow rising carotid pulse.

2.      Blood pressure:

·         Low systolic pressure.

·         High diastolic pressure.

·         Narrow pulse pressure.

3.      Precordium:

·         Apex beat shifted downwards & outwards.

·         Thrusting left ventricle.

·         Ejection systolic murmur.

·         Signs of LVH.

·         Signs of LVF, e.g.

-Bilateral basal crepitations.

-Pulmonary oedema.

Investigations:

1.      ECG:

·         Left ventricular hypertrophy (usually)

·         Left bundle branch block (LBBB).

2.      Chest X-ray:

·         May be normal, sometimes enlarged left ventricle.

·         Dilated ascending aorta on P/A view.

·         Calcified valve on lateral view.

3.      Echo:

·         Calcified valve with restricted opening.

·         Hypertrophied left ventricle.

4.      Doppler:

·         Measurement of severity of stenosis.

·         Detection of associated aortic regurgitation.

5.      Cardiac catheterization (if coronary disease present):

·         Systolic gradient between LV & aorta.

·         Post-stenotic dilatation of aorta.

·         Regurgitation of aortic valve may be present.

Management:

[A] Medical treatment: In asymptomatic patients conservative management may be appropriate:

·         Angina: β-blockers (not GTN or isosorbide dinitrate)

·         LVF: Diuretics.

·         Antibiotic prophylaxis against infective endocarditis.

Indication for surgery arises when patient develops angina symptoms of low cardiac output or heart failure.

[B] Surgical treatment (valve gradient > 50 mm hg)

·         Aortic balloon valvuloplasty (palliative treatment)

·         Aortic valve replacement (specific treatment)

Reference:

1.      Davidson’s Principles and Practice of Medicine, 21^st edition

2.      Wikipedia the free encyclopedia.