Aortic Stenosis Flashcards
What is the definition of aortic stenosis?
Narrowing of the left ventricular outflow at the level of the aortic valve
What is the aetiology of aortic stenosis?
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
What is the epidemiology of aortic stenosis?
Present in 3% of 75 yr olds
More common in males
Those with bicuspid aortic valve present earlier
What are the presenting symptoms of aortic stenosis?
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)
What are the signs of aortic stenosis upon physical examination?
Narrow pulse pressure
Slow-rising pulse
Thrill in the aortic area (only if severe)
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
What are the appropriate investigations for aortic stenosis?
ECG
- 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
CXR
- Post-stenotic enlargement of ascending aorta
- Calcification of aortic valve
Echocardiogram
- 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
Cardiac angiography
- 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
