Canonical: https://echosuite.app/guides/mr-pisa/

# Mitral regurgitation PISA calculator: EROA and regurgitant volume

Connect PISA radius, aliasing velocity and the MR Doppler signal to effective regurgitant orifice area and regurgitant volume. The tool retains its acquisition limits and integrated-assessment context.

Created by [Mohammed Kamareddine, MD](https://echosuite.app/about/) · [Sources & educational scope](https://echosuite.app/about/)

[Open interactive calculator →](https://echosuite.app/calculators/#mr-pisa)

## Method

EROA = 2πr²Vₐ ÷ Vmax; RVol = EROA × VTI

Use the measurement units shown below. Some fields apply only to a selected method or condition; follow the interactive tool’s method choices. The interactive tool keeps missing measurements incomplete and provides its method-specific results and reference context.

## Measurements and acquisition

### PISA radius  cm

Color Doppler · peak-flow frame

- Zoom on the valve and center the flow-convergence region.
- Shift the color baseline until the shell is as hemispheric as possible.
- Measure from the regurgitant orifice to the first aliasing boundary along the jet centerline.

### Aliasing velocity magnitude  cm/s

Shifted color scale · absolute cm/s

- Use the same color-Doppler frame used for the radius.
- Read the Nyquist limit after baseline shift, not the jet velocity.
- Enter the absolute displayed value in cm/s.

### MR Vmax  m/s

Continuous-wave Doppler

- Align the CW cursor as parallel as possible to the jet.
- Acquire a dense, complete envelope without truncation.
- Measure the highest absolute velocity on the selected envelope.

### MR VTI  cm

Continuous-wave Doppler trace

- Use the same aligned CW recording as the peak velocity.
- Trace the outer edge of the dense envelope for the relevant phase.
- Use the machine-reported VTI in centimeters.

### Total LV stroke volume  mL

Enter the measured value in the displayed unit

- Confirm the variable matches the selected formula.
- Use the unit displayed beside the field.
- Keep measurements from the same representative hemodynamic state.

## Sources and method context

American Society of Echocardiography · 2017 · Recommendations for Noninvasive Evaluation of Native Valvular Regurgitation · PISA method pp. 9–10 · Figure 5; MR Table 7 pp. 22–24; Table 8 and Figure 18 pp. 29–30

[Primary reference](https://www.asecho.org/wp-content/uploads/2017/04/2017VavularRegurgitationGuideline.pdf)

- Equation & timing · Pages 9–10 · Figure 5

Hemispheric PISA flow, EROA and regurgitant-volume equations; pair radius with aliasing velocity and peak jet velocity at the same regurgitant time point.

- Acquisition & limitations · Pages 22–24 · Table 7

Beam alignment, zoom, variance off, baseline shift, radius placement, and limitations of eccentric, constrained, multiple or noncircular jets.

- Severity integration · Pages 29–30 · Table 8 and Figure 18

Four quantitative MR grades and the requirement to integrate anatomy, vena contracta, pulmonary-vein flow, chamber response and data quality.

Catalogue review status: Exact guideline locator mapped · clinical sign-off pending

These pages describe the educational tool. Interpret measurements with the complete clinical context and the method’s acquisition limitations.

## Keep exploring

- [Apical four chamber acquisition guide](https://echosuite.app/guides/views/apical-four-chamber/) · [Open in Probe Lab](https://echosuite.app/#a4c)
- [Apical two chamber acquisition guide](https://echosuite.app/guides/views/apical-two-chamber/) · [Open in Probe Lab](https://echosuite.app/#a2c)
- [Apical three chamber (apical long axis) acquisition guide](https://echosuite.app/guides/views/apical-three-chamber/) · [Open in Probe Lab](https://echosuite.app/#a3c)
- [Aortic regurgitation PISA calculator](https://echosuite.app/guides/ar-pisa/)
- [Aortic regurgitation calculator: continuity method](https://echosuite.app/guides/ar-continuity/)
- [Mitral regurgitation calculator: continuity method](https://echosuite.app/guides/mr-continuity/)
- [Tricuspid regurgitation calculator: PISA quantification](https://echosuite.app/guides/tr-pisa/)

[All echo guides](https://echosuite.app/guides/) · [Learning paths](https://echosuite.app/learn/)