77909-0
LOINC Code
| LOINC code | 77909-0 | |
|---|---|---|
| name | ||
| description | The effective regurgitant orifice area (EROA) is the size of the defect where the valve leaflets are not aligning normally (coaptation defect). The severity of regurgitation is related to the EROA. Proximal isovelocity surface area (PISA) is a method for calculating the EROA using color flow Doppler and is based on flow dynamics and the continuity principle, which 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. The EROA is calculated from the flow and peak velocity at the regurgitant orifice, where the flow is based on the radius at the orifice and the Nyquist limit (aliasing velocity), which is the velocity at which the color flow switches from red to blue or blue to red, and the peak velocity is measured using continuous wave Doppler of the jet. [PMID: 17898369] | |
| status | ACTIVE | |
Fully-Specified Name | ||
| component | Effective regurgitant orifice area | |
| property | Area | |
| time | Pt = Point in time: To identify measures at a point in time. This is a synonym for “spot” or “random” as applied to urine measurements. | |
| system | Aortic valve | |
| scale | Qn = Quantitative: The result of the test is a numeric value that relates to a continuous numeric scale. Reported either as an integer, a ratio, a real number, or a range. The test result value may optionally contain a relational operator from the set {<=, <, >, >=}. Valid values for a quantitative test are of the form "7", "-7", "7.4", "-7.4", "7.8912", "0.125", "<10", "<10.15", ">12000", 1-10, 1:256 | |
| method | US.doppler+Calculated by PISA method | |
Additional Names | ||
| short name | AO; AoV; AV; AVA; Calc; Calculation; CARD.US; Cardio; Cardiology; DOP; DUPLEX; Echography; ERO; EROA; Heart Disease; Point in time; Proximal Isovelocity Surface Area; QNT; Quan; Quant; Quantitative; Random; ROA; Sonogram; Sonograph; Sonography; ULS; Ultra | |
Basic Attributes | ||
| class | CARD.US | |
| type | 2 Clinical | |
| order vs. observation | AV EROA PISA | |
| formula (readable) | Effective regurgitant orifice area (EROA) = [(2 x Pi x r^2) x Nyquist limit]/Vmax | |
| example UCUM units | cm2 The Unified Code for Units of Measure (UCUM) is a code system intended to include all units of measures being contemporarily used in international science, engineering, and business (www.unitsofmeasure.org) | |
History/Usage | ||
| first released | ||
| last updated | 2.56 | |
| last change type | NAM - change to Analyte/Component | |
| change reason | cm2 | |
Related Names | ||
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