Canonical: https://echosuite.app/guides/pvr/

# Pulmonary vascular resistance calculator: echo Doppler method

Review the Doppler inputs, formula and method qualifications used by EchoSuite’s pulmonary vascular resistance tool.

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

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

## Method

PVR = 10 × TR Vmax ÷ RVOT VTI + 0.16

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

### TR Vmax  m/s

CW Doppler through the TR jet

- Search RV inflow, apical four-chamber, and subcostal windows; use the highest well-aligned signal.
- Trace the dense primary edge (‘chin’), not faint overgained noise, and reject truncated triangular envelopes when estimating pressure.
- Average three representative beats; in atrial fibrillation average 5–10 beats and exclude post-pause or post-ectopic velocities.

### RVOT VTI  cm

PW Doppler just below the pulmonary valve

- From the PA-bifurcation PSAX view, place a 1–2 mm PW sample in the distal RVOT just beneath the pulmonary valve.
- Optimize scale, baseline, wall filter, and beam alignment so the entire systolic envelope is visible.
- Trace the modal envelope for VTI; measure acceleration time from flow onset to peak velocity and interpret cautiously when heart rate is <60 or >100 bpm.

## Sources and method context

American Society of Echocardiography · 2025 · Guidelines for the Echocardiographic Assessment of the Right Heart in Adults and Special Considerations in Pulmonary Hypertension · Pulmonary Vascular Resistance section · JASE p. 167

[Primary reference](https://www.asecho.org/wp-content/uploads/2026/08/ASE-Right-Heart-Guidelines-May-2025.pdf)

- Equation and thresholds · PVR section and key points · JASE p. 167

The Abbas equation, normal PVR below 1.5 WU, and abnormal PVR above 2.0 WU.

- Clinical limitations · PVR recommendations · JASE p. 167

Unreliability above 8 WU, nonroutine-use recommendation, and the requirement not to substitute echo PVR for invasive hemodynamics.

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)
- [RV outflow acquisition guide](https://echosuite.app/guides/views/rv-outflow/) · [Open in Probe Lab](https://echosuite.app/#rvOutflow)
- [Parasternal short axis, aortic valve level acquisition guide](https://echosuite.app/guides/views/psax-aortic-valve/) · [Open in Probe Lab](https://echosuite.app/#psaxAV)
- [Right atrial pressure assessment: IVC and hepatic vein flow](https://echosuite.app/guides/rap/)
- [Right atrial size calculator and measurement guide](https://echosuite.app/guides/ra-size/)
- [Right ventricular size calculator and measurement guide](https://echosuite.app/guides/rv-size-calc/)
- [Right ventricular function calculator: TAPSE, FAC and coupling](https://echosuite.app/guides/rv-function-calc/)

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