Aortic Stenosis – AS

Dr Tom Leach

8 years ago

Contents

Introduction
Causes
- Congenital
- Senile Calcification
Signs
Symptoms
Investigations
Prognosis
Management
References
Related Articles

Introduction

Aortic Stenosis is the narrowing of the three cusps that form the aortic valve. It is distinct from aortic sclerosis which is generally a milder precursor to aortic stenosis.

Aortic Stenosis is typically progressive, with symptoms becoming gradually worse over time. The first presentation usually occurs with shortness of breath on exertion.

Causes

Congenital

Bicuspid Valve
Williams Syndrome

Senile Calcification

THE most common cause
Look for corneal arcus

Aortic Stenosis seen on post mortem. The aorta has been removed in this image to better demonstrate the aortic valve

Signs

Ejection Systolic murmur best heard in the aortic area, ( Right 2nd intercostal space at border of sternum), radiating to the caroitds.
Slow-rising pulse, with a narrow pulse pressure (difference between systolic and diastolic pressures is small)
Heave – but apex beat is not displaced
Possible signs of:
- Heart failure / pulmonary hypertension: crackles at the lung bases, pink frothy sputum, oedema etc
- AF – irregularly irregular pulse

Symptoms

Angina
Syncope
Dyspnoea
Signs of any valve defect
- Fatigue
- Dyspnoea

Investigations

ECG

L – LBBB – due do calcification
L – Left Axis Deviation
L – LVH
P – Poor R wave progression (i.e. depolarisation of the ventricles is slow)

Doppler Echo

Used to estimate the pressure across the valve.

0 mmHg – normal valve
<30 mmHg – mild aortic stenosis
30-50 mmHg – moderate aortic stenosis
>50 mmHg – severe aortic stenosis

Cardiac Catheterisation

This can assess the actual gradient across the valve as well as check for co-existing CAD

Prognosis

If untreated

This can be predicted with the presence of symptoms:

Angina present – 2 years
Syncope present – 1 year
Dyspnoea present – 6 months

Management

Surgical –if symptomatic, then the prognosis is poor (above) and prompt valve replacement is recommended. Valve replacement is also recommended for patients with ECG signs, and moderate to severe disease on Doppler / cardiac catheterisation.
- Patients should be placed on antibiotics to prevent bacterial endocarditis

Valve replacements

Prosthetic – last about 10 years, after which time, may require another replacement. No need for long term anticoagulant therapy.
Metal –last a life time, but require anticoagulant therapy for life. Also noisy (often make a loud ‘click’ sound). There are three types of metal valve

Tilting disc
Double tilting disc
Ball in a cage