aortic stenosis Flashcards
define aortic stenosis?
narrowing of the left ventricular outflow at the level of the aortic valve
summarise the epidemiology of aortic stenosis?
present in 3% of 75 year olds
most common in males
those with bicuspid aortic valve present earlier
explain the aetiology/ risk factors of aortic stenosis
secondary to rheumatic heart disease
congenital: calcification of congenital bicuspid aortic valve, William’s syndrome ( supraventricular aortic stenosis)
calcification/ degeneration of aortic valve in the elderly ( senile calcification)
chronic kidney disease
aortic sclerosis- get EJ systolic murmur but no radiation to carotids-> eventually becomes aortic stenosis
more than 60
what is a bicuspid aortic valve
aortic valve that has 2 leaflets instead of 3
what are the presenting symptoms of aortic stenosis
may be asymptomatic initially
Think of AS in an elderly person with chest pain, exertional dyspnoea or syncope
angina ( due to increased oxygen demand of the hyeprtrophied left ventricle)
syncope or dizziness on exercise ( due to outflow obstruction)
symptoms of heart failure ( orthopnoea, dyspnoea)
what are the signs of aortic stenosis on examination?
low BP
narrow pulse pressure
slow-rising pulse
thrill in aortic area ( only if severe)
heaving, unidisplaced 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?
echocardiogram
doppler echo can estimate gradient across valves
ECG
CXR
Assess left ventricular function
cardiac angio
What can be seen on the Echocardiogram to diagnose aortic stenosis?
visualises structural changes of valves and level of stenosis ( Valvar, supravalvar or subvalvar)
estimation of aortic valve area and pressure gradient across the valve in systole
what can be seen on the doppler echo when diagnosing aortic stenosis?
doppler echo can estimate gradient across valves
severe stenosis if gradient> /=50mmHg and valve area <1cm^2
if aortic jet velocity >4m/s risk of complications is increased
what can be seen on the ECG to diagnose aortic stenosis?
P mitrale ( left atrial enlargement)
signs of left ventricular hypertrophy
- deep in S in V1/2
- Tall R in v5/v6
- iNVERTED t waves in I, aVL and V5/6
- left axis deviation
LBBB or complete AV block
What can be seen on the chest x-ray when diagnosing aortic stenosis?
post stenotic enlargement of ascending aorta
calcification of aortic valve
LVH but this will look normal as it is hypertrophied not dilated
How does doing a cardiac angiography help?
allows differentiation from other causes of angina ( eg MI)
helps assess valve gradient, LV function and coronary artery disease
allows assessment of concomitant coronary artery disease
50% of patients with severe aortic stenosis have significant coronary artery disease
Describe the management for aortic stenosis?
If symptomatic, prognosis is poor without surgery: 2–3yr survival if
angina/syncope; 1–2yr if cardiac failure.
If moderate-to-severe and treated medi- cally, mortality can be as high as 50% at 2yrs, therefore prompt valve replacement is usually recommended.
In asymptomatic patients with severe AS and a dete- riorating ECG, valve replacement is also recommended.
If the patient is not medically fit for surgery, percutaneous valvuloplasty/replacement (TAVI = transcatheter aortic valve implantation) may be attempted.
