AORTIC STENOSIS

Question 1

Causes (2)

Answer 1

• Calcification: bicuspid if young, tricuspid if elderly
• Rheumatic heart disease

Question 2

Pathophysiology (3)

Answer 2

• Stenotic valve —> LV outflow obstruction —> LVH
• Even smaller valve —> CO fails to increase on exertion —> angina on exertion
• LVH —> LV dilatation —> LV dysfunction/MR

Question 3

Symptoms (2)

Answer 3

• Asymptomatic for years, then develop triad: angina, exertional syncope, dyspnea (SAD)
• +/- symptoms of HF —> poor prognosis

Question 4

Signs (5)

Answer 4

• Normal S1, soft muffled S2
• S4 added sound (left atrium contracts forcefully against a stiff or hypertrophic ventricle; atrial gallop)
• AS SEM: Systolic ejection murmur (aka harsh crescendo decrescendo), best at right upper sterna border, radiating to carotids
• Parvus et tardus (low volume slow rising carotid pulse)
• Pulse pressure may be reduced

Question 5

Clinical signs of severity (6)

Answer 5

• Symptomatic (dyspnea is most severe symptom)
• Soft S2 and paradoxical splitting of S2 (P2 heard earlier than A2)
• Added S4
• Systolic thrill at aortic area
• Parvus et tardus
• Heaving apex

Question 6

Diagnosis (4)

Answer 6

1- CXR:
- Calcified aortic valve
- Post-stenotic aortic dilatation (mostly in bicuspid)
- Normal size (late may show LA and LV dilatation)
- Pulmonary edema
2- ECG:
- LV strain pattern (ST depression, T wave inversion)
- LVH: Deep S in V1 V2, tall R in V5 V6, both together > 35mm
3- Echo with doppler: Signs of severity on echo:
- Aortic valve area < 1cm2
- Peak flow velocity > 4m/s
- Mean pressure gradient > 40mmHg
4- Coronary angiography before surgery to look for associated CAD

Question 7

Treatment (2)

Answer 7

• Aortic valve replacement
• If open is unsuitable —> TAVR (transcatheter aortic valve replacement)
  
  • Higher risk of residual AR and need for pacemaker