Audience: echocardiographers and cardiology trainees. Evidence reviewed: September 2026.
Key message
Right-sided filling pressure cannot be read reliably from one Doppler waveform. Integrate inferior vena cava behaviour, tricuspid inflow, annular tissue Doppler, hepatic-vein flow, chamber morphology and the clinical setting.
Acquire physiology, not just traces
Record rhythm, heart rate, respiration and ventilation status. Tricuspid inflow is sampled at the leaflet tips in the apical four-chamber view. Tissue Doppler is obtained from the lateral tricuspid annulus. Hepatic-vein pulsed-wave Doppler is usually acquired from the subcostal window with a sample volume positioned within a hepatic vein, avoiding the vena caval junction.
| Signal | Expected information | Major confounders |
|---|---|---|
| Tricuspid E and A | Early filling and atrial contribution | Age, heart rate, respiration, rhythm and significant TR |
| Lateral e′ | Annular relaxation velocity | Regional dysfunction, tethering and translational motion |
| Hepatic-vein S, D and atrial reversal | Right-atrial pressure pattern and systolic forward flow | TR, AF, pacing and ventilation |
| IVC size and collapse | Estimate of right-atrial pressure | Mechanical ventilation, athletic physiology and abdominal pressure |
How to interpret the components
Tricuspid E/A and deceleration time change with relaxation and pressure but have substantial overlap between normal and abnormal states. The E/e′ ratio on the right side has a weaker and more context-dependent relationship with right-atrial pressure than its familiar left-sided counterpart; it should not be used in isolation.
Normal hepatic-vein flow is generally systolic dominant. Reduced systolic predominance may accompany raised right-atrial pressure, but systolic flow reversal is particularly associated with severe tricuspid regurgitation. In atrial fibrillation, the atrial reversal wave disappears and beat selection becomes critical.
IVC diameter and inspiratory collapse provide a conventional estimate of right-atrial pressure in spontaneously breathing adults, but intermediate or discordant findings should prompt secondary signs rather than false precision. Mechanical ventilation invalidates simple application of spontaneous-breathing cut-offs.
Constrictive and restrictive physiology
Marked respiratory variation in atrioventricular inflow, hepatic-vein expiratory diastolic reversal, preserved or increased medial mitral e′ and septal shift can support constrictive physiology. No single sign is definitive. Technical quality, chronic obstructive pulmonary disease, volume status, rhythm and intrathoracic-pressure changes must be considered.
A practical synthesis
- First decide whether the signal is technically valid.
- Describe IVC findings and the assumptions used to estimate right-atrial pressure.
- Assess TR severity before interpreting hepatic-vein systolic reversal.
- Integrate RV size/function, septal configuration and pulmonary-pressure probability.
- State uncertainty when signals conflict or ventilation/rhythm limits interpretation.
Selected references
- ASE 2025 right-heart and pulmonary-hypertension guideline.
- BSE right-heart assessment guideline.
- 2022 ESC/ERS pulmonary-hypertension guideline.
Educational material only. Haemodynamic estimates require clinical correlation and invasive confirmation when management depends on precise pressure measurement.
The Cardiac Compass 