Aortic stenosis

Question 1

DEFINITION of aortic stenosis

Answer 1

narrowing of the left ventricular outflow at the level of the aortic valve

Question 2

Explain the aetiology and risk factors of aortic stenosis

Answer 2

Stenosis can be secondary to rheumatic heart disease (MOST COMMON WORLDWIDE)

Calcification of a congenital bicuspid aortic valve

Calcification/degeneration of a tricuspid aortic valve in the elderly

Question 3

Summarise the epidemiology of aortic stenosis

Answer 3

Present in 3% of 75 yr olds

More common in males

Those with bicuspid aortic valve present earlier

Question 4

Recognise the presenting symptoms of aortic stenosis

Answer 4

May be ASYMPTOMATIC initially

Angina (due to increased oxygen demand of the hypertrophied left ventricle)

Syncope or dizziness on exercise (due to outflow obstruction)

Symptoms of heart failure (e.g. dyspnoea, orthopnoea)

Question 5

Signs of aortic stenosis on examination

Answer 5

Narrow pulse pressure

Slow-rising pulse- Palpable heaving apex (LeftVentricularHypertrophy) Ejection Systolic Murmur, often radiating to the carotids and best heard in the aortic region.

Thrill in the aortic area (only if severe)- palpable vibration

Forceful sustained thrusting undisplaced apex beat

Ejection systolic murmur at the aortic area, radiating to the carotid artery

Second heart sound may be softened or absent (due to calcification)

A bicuspid valve may produce an ejection click

Question 6

Identify appropriate investigations for aortic stenosis

Answer 6

ECG
CXR
Echocardiogram
Cardiac angiography

Question 7

ECG

Answer 7

Signs of left ventricular hypertrophy

Deep S in V1/2

Tall R in V5/6

Inverted T waves in I, aVL and V5/6

Left axis deviation

LBBB

Question 8

CXR

Answer 8

Post-stenotic enlargement of ascending aorta

Calcification of aortic valve

Question 9

Echocardiogram

Answer 9

Visualises 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

Assess left ventricular function

Question 10

Cardiac angiography

Answer 10

Allows differentiation from other causes of angina (e.g. MI)

Allows assessment of concomitant coronary artery disease

NOTE: 50% of patients with severe aortic stenosis have significant coronary artery disease