Most common etiologies of AS
- Calcification of a normal aortic valve overtime with age
- Bicuspid aortic valve
- Rheumatic heart disease (usually associated with mitral valve disease)
Symptoms
- Dyspnea (most common)
- Angina
- Syncope
Diagnosis
- Physical exam
- Systolic ejection murmur at RUSB with radiation to the carotids
- Any maneuver that decreases blood flow across the valve will cause a decrease in the sound of murmur (e.g. valsalva, handrip, or standing) whereas anything that increases blood flow across the valve will increase the sound of the murmur (e.g. squatting)
- Transthoracic echo
- Severe AS is AVA < 1 cm2, mean gradient greater or equal to 40, or max velocity greater than 4 m/s
Low-flow, low-gradient AS
- If patient has an AVA < 1 cm2 but has a mean gradient < 35 mmHg, consider low-flow, low-gradient AS
- To determine whether there is an intrinsic problem with the valve versus a pseduo-aortic stenosis due to myocardial dysfunction, do a dobutamine stress echo
- If AVA remains unchanged and the mean gradient increases with dobutamine, the etiology is severe AS and the patient would benefit from valve replacement
- If the AVA increases and the mean gradient doesn’t increase, this is a pseudo-aortic stenosis and the patient can be managed medically
When to treat?
- Any patient who is symptomatic
- An asymptomatic patient with EF < 50 or who is getting another cardiac surgery
Treatment
- AVR > TAVR if the patient is a surgical candidate
- TAVR is good for high risk patients and has similar survival to AVR in high-risk patients
- AV balloon valvuloplasty is a short-term bridge to TAVR as it only lasts a few months
- Medical management is usually not beneficial if a patient has severe AS