aortic stenosis

Question 1

definition of AS

Answer 1

Narrowing of the left ventricular outflow at the level of the aortic valve.

Question 2

aeriology of AS

Answer 2

stenosis secondary to rheumatic heart disease

calcification of a congenital bicuspid aortic valvle

calcification/degeneration of a tricuspid aortic valve in elderly

Question 3

RF for AS

Answer 3

>60yrs

bicuspid valve

rheumatic heart disease

chronic kidney disease

Question 4

epidemiology of AS

Answer 4

3% of 75yr olds prevalence

men more

those with bicuspid valve may present earlier (as young adults)

Question 5

sx of AS

Answer 5

initially asymptomatic

angina - increased ox demand of the atrophied ventricles

syncope or dizziness on exercise

symptoms of HF eg dyspnoea

systemic emboli if endocarditis

sudden death

classic triad: angina, syncope, HF

Question 6

signs of AS

Answer 6

BP - slow rising pulse with narrow pulse pressure

• feel for diminished and delayed carotid upstroke

palpation

• thrill in aortic area (if severe)
• LV heave
• Forceful sustained thrusting undisplaced apex beat.

auscultation

• harsh ejection systolic murmur at aortic area, radiating to the carotid artery and apex
• Second heart sound (A2 component) may be softened or absent (because of calcification)
• rare: as stenosis worsens = A2 gets more delayed = get s2 then reversed splitting
• A bicuspid valve may produce an ejection click (s4)

Distinguish from aortic sclerosis1and hypertrophic obstructive cardiomyopathy(HOCM)

Question 7

Ix for AS

Answer 7

ECG
CXR
Echo

cardiac angiography

cardiac catheter

Question 8

ECG for AS

Answer 8

Signs of left ventricular hypertrophy (deep S wave in V1–2, tall R wave in V5–6, inverted T waves in I, aVL, V5–6 and left-axis deviation)

p-mitrale

poor R wave progression

LBBB or complete AV block

Question 9

CXR for AS

Answer 9

Post-stenotic enlargement of the ascending aorta

calcification of aortic valve.

LVH

calcified aortic valve

Question 10

echo for AS

Answer 10

Visualizes structural changes of the valves and level of stenosis (valvar, supravalvar or subvalvar).

Estimation of aortic valve area and pressure gradient across the valve in systole and left ventricular function may be assessed

severe stenosis if peak gradient >40mmHg (but beware the poor left ventricle not able to generate gradient) and valve area <1cm2.

If the aortic jet velocity is >4m/s (or is increasing by >0.3m/s per yr) risk of complications is increased

Question 11

cardiac angiography for AS

Answer 11

differentiation from other causes of angina

assess for concomitant coronary artery disease (50% people have it)

Question 12

cardiac catheter for AS

Answer 12

valve gradient

LV function

coronary artery disease

risks

embolic generation