Right atrial pressure assessment: IVC and hepatic vein flow
Review IVC and hepatic-flow inputs in EchoSuite’s right atrial pressure tool, with acquisition guidance and supporting reference context.
Method
RAP category from IVC diameter and inspiratory collapse
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
Measurement
Enter the measured value in the displayed unit
- IVC estimate
- Measured collapse
- Hepatic S / D
- Confirm the variable matches the selected formula.
- Use the unit displayed beside the field.
- Keep measurements from the same representative hemodynamic state.
IVC diameter cm
Subcostal long axis · M-mode or 2D
- From subcostal IVC long axis, measure end-expiratory diameter 0.5–3.0 cm proximal to the right-atrial ostium.
- Keep the calipers perpendicular to the IVC and observe variation with both a sniff and quiet respiration.
- Record whether inspiratory collapse is at least 50%; do not use collapse alone during positive-pressure ventilation.
Collapse with sniff
Subcostal long axis · M-mode or 2D
- At least 50%
- Less than 50%
- From subcostal IVC long axis, measure end-expiratory diameter 0.5–3.0 cm proximal to the right-atrial ostium.
- Keep the calipers perpendicular to the IVC and observe variation with both a sniff and quiet respiration.
- Record whether inspiratory collapse is at least 50%; do not use collapse alone during positive-pressure ventilation.
End-expiratory maximum cm
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.
Sniff minimum cm
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.
Same site and plane
Enter the measured value in the displayed unit
- Both walls tracked
- Out-of-plane / uncertain
- Confirm the variable matches the selected formula.
- Use the unit displayed beside the field.
- Keep measurements from the same representative hemodynamic state.
Peak forward S cm/s
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.
Peak forward D cm/s
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.
Usable forward peaks
Enter the measured value in the displayed unit
- Yes
- Systolic reversal
- Uncertain / limited
- Confirm the variable matches the selected formula.
- Use the unit displayed beside the field.
- Keep measurements from the same representative hemodynamic state.
Ventilation
Subcostal long axis · M-mode or 2D
- Spontaneous breathing
- Positive-pressure ventilation
- From subcostal IVC long axis, measure end-expiratory diameter 0.5–3.0 cm proximal to the right-atrial ostium.
- Keep the calipers perpendicular to the IVC and observe variation with both a sniff and quiet respiration.
- Record whether inspiratory collapse is at least 50%; do not use collapse alone during positive-pressure ventilation.
Secondary evidence when discordant
Subcostal long axis · M-mode or 2D
- None present
- One or more present
- Unavailable / uncertain
- From subcostal IVC long axis, measure end-expiratory diameter 0.5–3.0 cm proximal to the right-atrial ostium.
- Keep the calipers perpendicular to the IVC and observe variation with both a sniff and quiet respiration.
- Record whether inspiratory collapse is at least 50%; do not use collapse alone during positive-pressure ventilation.
Marked venous signs with IVC >2.5 cm
Subcostal long axis · M-mode or 2D
- No
- Yes
- From subcostal IVC long axis, measure end-expiratory diameter 0.5–3.0 cm proximal to the right-atrial ostium.
- Keep the calipers perpendicular to the IVC and observe variation with both a sniff and quiet respiration.
- Record whether inspiratory collapse is at least 50%; do not use collapse alone during positive-pressure ventilation.
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 · RAP section and Figure 3 · PDF pp. 19–20 and 23
- Primary IVC branches · RAP section and Table 4 · PDF pp. 19–20
End-expiratory IVC measurement, the 2.1-cm and 50% branches, and discrete 3, 8, 15, or selected 20-mmHg estimates.
- Discordant findings and caveats · RAP section · PDF p. 19
Secondary-index resolution, positive-pressure ventilation limitations, and caveats for athletes, pregnancy, and inadequate sniff.
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.
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