aortic stenosis

Question 1

define

Answer 1

narrowing of L ventricular outflow @ level of aortic valve= get decreased CO

Question 2

causes

Answer 2

• commonest cause: degenerative calcification (most common cause in older patients > 65 years)
• commonest cause worldwide:post-rheumatic disease [scar tissue leading to fibrosis]
• congenital:
  
  • bicuspid aortic valve (most common cause in younger patients < 65 years)
  • William’s syndrome (supravalvular aortic stenosis)
• subvalvular: HOCM

Question 3

s/s

Answer 3

Clinical features of symptomatic disease

• chest pain [angina]
• dyspnoea
• syncope

Features of severe aortic stenosis

• LVF- PND, orthopnoea, frothy sputum
• arrhythmias
• systemic emboli [if endocarditis]
• sudden death.
• narrow pulse pressure
• slow rising pulse
• delayed ESM- heard over R 2nd ic space sitting forward in end expiration- radiates to carotids
• soft/absent S2
• S4
• aortic thrill
• apex- forceful, non displaced [pressure overload]
• left ventricular hypertrophy or failure

Question 4

ddx

Answer 4

CAD

MR

aortic sclerosis

Question 5

ix

Answer 5

• ECG - left ventricular hypertrophy and strain
  
  • a tall R wave (greater than 25mm in V5 or V6), or R plus S greater than 35 mm (1)
  • a deep S in V1 or V2
  • if there is significant left ventricular ‘strain’ then there are also inverted T waves in V5 and V6 and possible ST depression
  • left axis deviation may also be present
  • QRS may be slightly prolonged
• chest radiography:
  
  • may show post-stenotic dilatation of the ascending aorta
  • there may be calcification of the aortic valve
• doppler and echocardiography - diagnostic of aortic stenosis
• cardiac catheterization and angiography - necessary only to exclude co-existing coronary artery disease.

Question 6

mx

Answer 6

• There is a risk of Stokes-Adams attacks and sudden death in patients with aortic stenosis

.

• if asymptomatic then observe the patient is general rule
• if symptomatic then valve replacement
• if asymptomatic but valvular gradient > 40 mmHg and with features such as left ventricular systolic dysfunction then consider surgery
• balloon valvuloplasty is limited to patients with critical aortic stenosis who are not fit for valve replacement
• give abx prophylaxis against infective endocarditis

Question 7

valve types

Answer 7

mechanical valves- last longer, need anticoag in young pts

bioprosthetic valves- dont need anticoag, but fail sooner [10-15yrs]

Question 8

complications

Answer 8

Complications include:

• left heart failure
• bacterial endocarditis
• sudden cardiac death

Question 9

prog

Answer 9

• survival differs according to symptoms

severe AS- 50% survival @ 18 mo

average survial

• angina- 5yrs
• syncope- 3 yrs
• dyspnoea- 2yrs