Aortic stenosis

Question 1

Define aortic stenosis.

Answer 1

Where the valve is narrowed, restricting blood flow.

Ejection systolic murmur:

• Reach a crescendo in mid-systole and die down before the 2nd heart sound.
• Heard over the aortic valve.

Question 2

What is the epidemiology of AS?

Answer 2

· Most common valvular disease.

· Older people - 70s and 80s.

Question 3

What is the pathophysiology of AS?

Answer 3

· Progresses gradually, causing obstruction to the left ventricular outflow with resultant hypertrophy.
· Ventricular dilatation and heart failure are late complications.
· Calcification of the normal tri-leaflet valves.

Question 4

What is the prognosis of AS?

Answer 4

· If symptomatic, survival is 2-3 years without surgery.

· 8-34% of patients die suddenly.

Question 5

What is the aetiology of AS?

Answer 5

· The most common cause under the age of 65 is a calcified bicuspid valve - more common in men.
· The most common cause over the age of 65 is senile calcific aortic stenosis - more common in women.
· In younger patients, the cause may be congenital or as a result of rheumatic fever.

Question 6

List the most common risk factors of AS?

Answer 6

· Senile aortic calcification - age >60 years - as a result of scarring and calcium build-up in the valve cusp.
· Congenitally bicuspid aortic valve - most common cause of AS in the young - birth defect where only two cusps grow instead of the normal three.
· Rheumatic heart disease - scarredaortic valve of rheumatic fever.
· CKD.

Question 7

What are the typical presenting symptoms of AS?

Answer 7

Initially asymptomatic.

Question 8

What late symptoms can patients present with?

Answer 8

· Angina. 
· Exertional dyspnoea.
· Chest pain. 
· Syncope. 
· Rapid, fluttering heart beat. 
· Sudden death.

Question 9

What signs may you notice o/e of a patient with AS?

Answer 9

· Plateau pulse - small volume and slow-rising.
· Narrow pulse pressure and low systolic.
· Heave at apex.
· Systolic thrill with radiation to the carotids.
· Paradoxicallysplit S2.
· Gallavardin’s phenomenon.
· Bleeding.
· Ejection systolic murmur.
· S2 diminished and single.
· Carotid/pulsus parvus et tardus.

Question 10

What is paradoxically split S2 and when does it mainly present?

Answer 10

Presents with more severe stenosis.

Aortic valve closure becomes so delayed that it follows pulmonic valve closure during expiration producing the paradoxically split S2, may be accentuated by left bundle branch block (LBBB).

Question 11

What is Gallavardin phenomenon?

Answer 11

A musical quality, holosystolic murmur is present at the apex of the heart that occurs in older pts with calcific AS which may mimic mitral regurgitation - dissociation between the noisy and musical components of the systolic murmur.

Question 12

What investigations would you request if you suspected a patient had AS?

Answer 12

· ECG.

· ECHO.

Question 13

List some differentials.

Answer 13

· Aortic sclerosis.
· IHD.
· Hypertrophic cardiomyopathy.

Question 14

What is the treatment option for a clinically unstable AS patient?

Answer 14

Medical therapy or balloon valvuloplasty.

Question 15

What is the treatment option for a clinically stable and symptomatic AS patient?

Answer 15

· Valve replacement.
· Infective endocarditis abx prophylaxis.
· Long-term anticoagulation.
· If higher risk - transcatheter aortic valve replacement (TAVR).

Question 16

What is the treatment option for a clinically stable and asymptomatic AS patient?

Answer 16

Clinical and ECHO follow up or referral.

Question 17

Why are many cardiovascular drugs contraindicated in AS?

Answer 17

Because of their vasodilatory effects. They can cause a decrease in systemic vascular resistance, which increases the gradient across the valve, increasing the work the ventricle has to perform.

Question 18

What complications can occur>

Answer 18

· Acute congestive heart failure (CHF).
· Sudden cardiac death.
· Prosthetic valve infection.
· Thrombosis secondary to mechanical valve.