29448-8
Mitral valve Effective regurgitant orifice area by US.doppler+Calculated by PISA method
Active
Term Description
The Proximal Isovelocity Surface Area (PISA) method is based on convergent flow dynamics and the Continuity Principle. Proximal to the orifice, flow converges in hemispheric layers of equal velocity. The flow rate across any of these hemispherical isovelocity surfaces is equal to the area of the surface (which can be calculated from its radius) multiplied by the flow velocity at the surface. Choosing a PISA velocity equal to the aliasing velocity of the system is an easy way to visualize an isovelocity surface (which will appear as the surface where the Doppler color switches between red and blue) and measure the corresponding PISA radius from the center of the orifice to the surface. The Continuity Principle states that in the absence of a leak or additional flow into a conduit, the flow rate will be constant along the length of the conduit, whether the conduit is the heart or the regurgitant jet. So the flow rate through the regurgitant orifice is the same as the flow rate across the PISA surface. Dividing the flow rate by the peak velocity through the orifice (measured using continuous wave Doppler of the regurgitant jet) provides the effective regurgitant orifice area (EROA).
Source: DICOM
Part Description
LP72534-8 Effective regurgitant orifice area
Cardiac valve area can be measured (orifice area) or indirectly calculated (effective orifice area). Direct measurement can be done on echo, and calculations are based on other measurements such as blood flow volume and velocity. [DICOM] The effective orifice area is calculated based on the equation F=A×V, where F is flow, A is area and V is velocity. The velocity is measured directly with Doppler echo and indirectly during cardiac catheterization based on the Torricelli law from the transvalvular pressure gradient: V=√2gh, where g is the velocity of acceleration resulting from gravity and h is the pressure gradient. Therefore, for area as measured by cardiac catheterization, the formula is A=F/√2gh. PMID: 22547754
Source: Regenstrief LOINC
, PMID: 22547754
Fully-Specified Name
- Component
- Effective regurgitant orifice area
- Property
- Area
- Time
- Pt
- System
- Mitral valve
- Scale
- Qn
- Method
- US.doppler+Calculated by PISA method
Additional Names
- Long Common Name
- Mitral valve Effective regurgitant orifice area by US.doppler+Calculated by PISA method
- Short Name
- MV EROA PISA
Basic Attributes
- Class
- CARD.US
- Type
- Clinical
- First Released
- Version 2.03
- Last Updated
- Version 2.56 (NAM)
- Change Reason
- Added "area" to the Component to align with the other effective orifice terms
- Order vs. Observation
- Observation
Language Variants Get Info
Tag | Language | Translation |
---|---|---|
el-GR | Greek (Greece) | Επιφάνεια αποτελεσματικού στομίου παλινδρόμησης: Synonyms: Επιφάνεια |
es-AR | Spanish (Argentina) | US.DOPPLER.PISA: |
es-MX | Spanish (Mexico) | Área de orificio regurgitante eficaz: |
it-IT | Italian (Italy) | Area orifizio rigurgitante effettivo: Synonyms: Eco Ecografia cardiaca Ecografia.doppler Ecografia.doppler.calcolata Punto nel tempo (episodio) |
pt-BR | Portuguese (Brazil) | Orifício regurgitante efetivo: Synonyms: ; |
zh-CN | Chinese (China) | 有效反流口: Synonyms: 僧帽瓣 反流(回流、 |
Example Units
Unit | Source |
---|---|
cm2 | Example UCUM Units |
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