Patient-Prosthesis Mismatch (Indexed Effective Orifice Area)
Patient-prosthesis mismatch, graded by the indexed effective orifice area: EOAi = prosthesis effective orifice area (cm2) divided by patient body surface area (m2).
Open the calculator → Runs in your browser. Data leaves only if you deliberately send a problem report from the interactive tool.
Example
- Valve position
- Mitral
- Prosthesis effective orifice area
- 1.6 cm^2
- Patient body surface area
- 2.0 m^2
Result: EOAi 0.80 cm2/m2, severe mismatch.
The tool opens with these values already filled in. Replace them with your own.
What the result means
- Aortic
- Above 0.85 not clinically significant; 0.65 to 0.85 moderate; below 0.65 severe.
- Mitral
- Above 1.2 not clinically significant; above 0.9 to 1.2 moderate; 0.9 or below severe. An EOAi of 1.0 is normal aortic and moderate mitral.
- Boundary
- The cited aortic source defines severe as below 0.65; later tables define it as 0.65 or below.
- Scope
- A hemodynamic relationship, not prosthesis failure, not a prediction, and not an indication for reoperation.
What you enter
- Valve position.
- Prosthesis effective orifice area.
- Patient body surface area.
Full field descriptions
- Valve position. REQUIRED and never assumed - the thresholds are not interchangeable, and an EOAi of 1.0 is normal aortic but moderate mitral [aortic = Aortic, per Pibarot and Dumesnil, Heart 2006; mitral = Mitral, per Magne and colleagues, Circulation 2007]
- Prosthesis effective orifice area. Use the MEASURED or REFERENCE effective orifice area, not the labelled valve size, which is a manufacturing dimension and overstates the opening.
How this is calculated
- Formula
- EOAi = prosthesis effective orifice area divided by body surface area. Use the measured or reference EOA, not the labelled size.
Pibarot P, Dumesnil JG. Prosthesis-patient mismatch: definition, clinical impact, and prevention. Heart. 2006;92(8):1022-1029 (aortic). Mitral grading: Magne J, et al. Circulation. 2007;115(11):1417-1425. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.