Cardiology: Aortic Stenosis Notes
Causes
- Congenital
- Bicuspid Valve
- Williams Syndrome
- Senile Calcification
- THE most common cause
- Look for corneal arcus
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)
- Dopple 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 – 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
Notes by Tom Leach
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