Aortic valve stenosis is usually defined by restricted systolic opening of the valve leaflets, with a mean transvalvular pressure gradient of at least 10 mm Hg.
Indications for aortic valve replacement (AVR) in aortic stenosis (AS)
Class I: There is evidence and/or general agreement that AVR is indicated in patients with AS in the following settings
- Symptomatic severe AS.
- Severe AS in patients undergoing coronary artery bypass graft surgery or surgery on the aorta or other heart valves.
- Severe AS with a left ventricular ejection fraction less than 50 percent.
Class IIa: The weight of evidence or opinion is in favor of the usefulness of AVR in patients with AS in the following setting
- Moderate AS in patients undergoing coronary artery bypass graft surgery or surgery on the aorta or other heart valves.
Class IIb: The weight of evidence or opinion is less well established for the usefulness of AVR in patients with AS in the following settings
- Severe AS in asymptomatic patients who have an abnormal response to exercise such as the development of symptoms or hypotension.
- Severe AS in asymptomatic patients with a high likelihood of rapid progression (as determined by age, valve calcification, and coronary heart disease).
- Severe AS in asymptomatic patients in whom surgery might be delayed at the time of symptom onset.
- Mild AS in patients undergoing coronary artery bypass graft surgery in whom there is evidence, such as moderate to severe valve calcification, that progression may be rapid.
- Extremely severe AS (aortic valve area less than 0.6 cm2, mean gradient greater than 60 mmHg, and aortic jet velocity greater than 5.0 m/sec) in asymptomatic patients in whom the expected operative mortality is 1 percent or less.
Class III: There is evidence and/or general agreement that AVR for AS is not useful in the following settings
- For the prevention of sudden cardiac death in asymptomatic patients who have none of the class IIa or IIb findings.
Severity of aortic stenosis in adults
| Aortic jet velocity, m/sec | Mean gradient, mmHg | Valve area, cm2 | |
| Normal | </=2.0 | <5 | 3.0-4.0 |
| Mild | <3.0 | <25 | >1.5 |
| Moderate | 3.0-4.0 | 25-40 | 1.0-1.5 |
| Severe | >4.0 | >40 | <1.0* |
Critical aortic stenosis has been defined hemodynamically as a valve area <0.75 cm2 and/or an aortic jet velocity >5.0 m/sec. However, the decision about valve replacement is not based solely on hemodynamics as some patients who meet these criteria are asymptomatic, while others with less severe measurements are symptomatic. In patients with severe aortic stenosis who also have a low cardiac output state the aortic jet velocity and mean gradient may be lower than indicated above (low-gradient aortic stenosis).
* Severe aortic stenosis is also considered to be present if the valve area indexed by body surface area is <0.6 cm2/m2.
References:
- Bonow RO, Carabello BA, Chatterjee K, et al. 2008 Focused update incorporated into the ACC/AHA 2006 guidelines for the management of patients with valvular heart disease: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Revise the 1998 Guidelines for the Management of Patients With Valvular Heart Disease): endorsed by the Society of Cardiovascular Anesthesiologists, Society for Cardiovascular Angiography and Interventions, and Society of Thoracic Surgeons. Circulation 2008; 118:e523. [Medline]
- Maganti K, Rigolin VH, Sarano ME, Bonow RO. Valvular heart disease: diagnosis and management. Mayo Clin Proc. 2010 May;85(5):483-500. [Medline]
Created: Apr 04, 2012.
