Aortic Stenosis

Question 1

What are the three causes of aortic stenosis?

Answer 1

1. Calcification (generative) in the elderly
   - Affects >65’s
   - Risks high cholesterol, hypertension, smoking, diabetes
2. Congenital abnormality eg bicuspid valve
   - Abnormal valve = turbulent flow = fibrosis and calcification
   - Occurs at a younger age eg <65
3. Rheumatic heart disease
   - An autoimmune condition following a strep A (pyogenes) infection

Question 2

What is the pathophysiology of the problems caused by AS?

Answer 2

• Systolic dysfunction as heart cannot pump out a normal proportion of it’s EDV
• Leads to ventricular hypertrophy
• This can lead to diastolic dysfunction due to impaired relaxation and reduced compliance
• Leads to left sided heart failure

Question 3

What are the classic triad of symptoms?

Answer 3

SAD

• Syncope on exertion
• Angina
• Dyspnoea

Question 4

Why may patients get epistaxis/bruising?

Answer 4

• Turbulent flow across the aortic valve can lead to an acquired von Willebrand deficiency
• High shear forces induces structural abnormalities in the shape of the protein leading to clotting abnormalities

Question 5

What murmur would be present in aortic stenosis?

Answer 5

Ejection systolic murmur, radiating to the carotids

Question 6

What signs would be present in a patient with aortic stenosis, other than a murmur?

Answer 6

• Slow rising pulse
• Narrow pulse pressure (<40)
• Heaving, non displaced apex beat
• Aortic thrill

Question 7

How would you investigate suspected AS?

Answer 7

Bedside -

• Observations
• Blood pressure
• 12 lead ECG

Bloods -

• FBC
• U+E
• Cholesterol
• Clotting factors

Imaging -

• CXR
• Echocardiogram

Question 8

What would a 12 lead ECG show in AS?

Answer 8

Left ventricular hypertrophy

• Deep S waves V1, V2
• Tall R waves V5, V6
• LAD
• Poor R wave progression

Question 9

What would a CXR show in AS?

Answer 9

• Cardiomegaly if in heart failure
• Post stenotic dilation of ascending aorta
• Calcified aortic valve

Question 10

What is the diagnostic test for AS?

Answer 10

Echocardiogram

- Allows assessment of the valve area, ejection fraction and ventricular hypertrophy

Question 11

What is the management for AS?

Answer 11

Surgical valve replacement

• Mechanical valve - Long term anticoagulation, long lifespan for younger patients
• Bioprosthetic valve - Suited for older patients

Question 12

What is the management for patients unfit for surgery?

Answer 12

1. Percutaneous valvuloplasty/valvulotomy
   - Stenotic lesions forced apart percutaneously with a balloon
2. TAVI
   - Transcatheter aortic valve implantation