Aortic Stenosis Flashcards
Causes of aortic stenosis (AS).
Senile calcification aka calcific aortic valvular disease is most common.
Congenital like bicuspid valve and Williams syndrome
Rheumatic fever
CKD
SLE
Paget’s disease
Risk factors of senile calficification.
Old age
Male
Elevated lipoprotein A and LDL cholesterol
HTN
Diabetes
Smoking
Progression of AS.
Increased left ventricular pressure leading to LV hypertrophy.
This leads to relative ischaemia of the LV myocardium -> angina, arrhythmias and LVF.
With exercise the symptoms gets worse and BP may fall as cardiac output can’t match demand.
Coronary ischaemia worsens and the myocardium fails and arrhythmias develop.
Classic triad of AS.
Angina
Syncope
Heart failure
Other symptoms of AS.
SOB
Dizziness
Faints
Systemic emboli if endo
Sudden death
Murmur of AS
Ejection systolic murmur that is usually diamond-shaped (crescendo-decrescendo).
High-pitched
Radiating to carotid/neck.
This is best heard in 2nd intercostal space on the right.
Signs of AS.
Pulse - Sinus rhythm, low volume and slow rising
Narrow pulse pressure
Non-displaced apex beat
Systolic thrill in aortic area
Ejection click, soft A2 and S4.
Ejection systolic murmur that is usually diamond-shaped (crescendo-decrescendo). Radiating to carotid/neck. This is best heard in 2nd intercostal space on the right.
Investigations in AS.
ECG
CXR
Echocardiogram (diagnostic)
Doppler Echo
Cardiac catherisation
ECG findings in AS.
LV hypertrophy with strain pattern - depressed ST segment and T-wave inversion in I, aVL, V5 and V6.
P-mitrale (left atrial delay)
Poor R-wave progression
LBBB
Complete AV block
CXR findings in AS.
LV hypertrophy
Calcified aortic valve
Post-stenotic dilation of ascending aorta
What is doppler ECHO used for?
Can estimate the gradient across valves.
Severe stenosis if peak gradient > 40 mmHG and valve area < 1cm2.
If aortic jet velocity is > 4 m/s there are risks of complications as well.
Differentials of AS.
Hypertrophic cardiomyopathy
Aortic sclerosis
How is AS best assessed?
Echocardiography
How is severity of AS graded?
Indications of surgery in AS.
Symptomatic regardless of severity
Asymptomatic severe AS with left ventricular systolic dysfunction (LVEF < 50%)
Asymptomatic severe AS with abnormal exercise test (Symptoms/drop in BP ST changes)
Asymptomatic severe or moderate AS at time of other cardiac surgery like CABG.
