Aortic stenosis

Question 1

definition?

Answer 1

Obstruction of blood flow through the aortic valve due to pathological narrowing.

Question 2

rf?

Answer 2

• Age>60
• Congenital bicuspid aortic valve
• Rheumatic heart disease
CKD

Question 3

ddx?

Answer 3

• Aortic sclerosis-less intense murmur and S2 normal split-no sig pressure gradient
• IHD-ECG shows abnormal thickening and Q waves
Hypertrophic cardiomyopathy-murmur increases when standing and squatting and had grip softens it-seen on echo

Question 4

Aetiology?

Answer 4

• Bicuspid aortic valves

Calcific aortic stenosis

Question 5

CP?

Answer 5

• RF's
• Dyspnoea
• Chest pain
• Syncope
• Ejection systolic murmur
• Small BP/low pulse pressure
• Systolic thrill over aorta
• Harsh crescendo/decrescendo late systolic ejection murmur-radiates to carotids in 2nd right ICS 
• S2 diminished and single
• Early systolic ejection click
• Carotid parvus et tardus-carotid upstroke is delayed and diminished
• Hand grip decreases intensity; standing from squatting decreases intensity 
S4 at apex

Question 6

pathophysiology?

Answer 6

• Usually 3-4 cm2
• Aortic valve doesn’t fully open-<1cm2
• Mech stress overtime-damages endothelial cells around valves-fibrosis and calcification-stiff
• Bicuspid-more risk of fibrosis and calc-stress less equally distributed
• Chronic rheumatic fever-repeated inflammation and repair-fibrosis-commissural fusion of valves
• Stiff-as LV contracts-high pressure-ejection click as snaps open
• Louder in systole and quieter as less blood flowing through/lower pressure as ejection occurs
• LV-higher pressures in contraction-concentric LV hypertrophy to increase contractility
• Less blood to body-risk of heart failure/organ failure
• Symptoms in exercise when increased demand
• Microangiopathic haemolytic anaemia-high blood pressure damages RBC’s -schistocytes-haemoglobinuria

Question 7

Investigations first line?

Answer 7

• CVS exam-See CP for findings
• ECG-LV hypertrophy due to pressure overload and absent Q waves and can have co-findings of AV block
• Transthoracic Echo/Doppler-high sensitivity and specificity
• Elevated aortic pressure gradient
• Measurement of valve area and LVEF

Question 8

investigation second line?

Answer 8

• Cardiac MRI-shows stenotic aortic valve
• Cardiac catheterisation-high sensitivity and specificity elevated aortic pressure gradient
• ECG stress testing-if asymptomatic-ST changes, BP or arrhythmias
• Dobutamine stress echo-pseudostenosis and contractile reserve

Question 9

management unstable?

Answer 9

Balloon valvuloplasty to temporarily relieve stenosis before surgery or transcatheter aortic valve replacement

Question 10

management stable first line?

Answer 10

• Surgical aortic valve replacement-Risk Assessment tools
• Mechanical/bioprosthetic valves inserted
• LT infective endocarditis AB prophylaxis
• LT anticoagulation-vit K antagonist if mech valves used

Question 11

management stable second line?

Answer 11

• TAVR-
• During TAVR, a new valve is mounted on a stent and deployed through a catheter, entering the heart either via the femoral artery or through the cardiac apex after a minimally invasive thoracotomy. The transaxillary and the transaortic routes may also be used. Advantages include the avoidance of cardiopulmonary bypass and median sternotomy.
• LT infective endocarditis AB prophyalxis
• LT anticoagulation-vit K antagonist if mech valves used

Question 12

management high risk?

Answer 12

• Same as above
• Consider risk factors for surgery
Surgery if contractile reserve and low flow and low gradient

Question 13

management non-surgery?

Answer 13

First line:
• TVAR
• LT AB and anticoagulation
Second line: 
• Medical therapy to improve co-morbidities and balloon valvuloplasty

Question 14

management asymptomatic?

Answer 14

• Follow up and consider prophylactic valve replacement

Question 15

prognosis ?

Answer 15

• Better with surgery
• Surgery is very effective-depends on risk-but EF and heart failure symptoms improve
• TAVR-better quality of life -5 yr mortality 72% compared to 94%

Question 16

complications?

Answer 16

• Acute CHF
• Sudden cardiac death
• Infection
• Thrombosis
• Re-stenosis
• Valve dehiscence