Tricuspid Stenosis: Severity Criteria and Gradient Measurement
General Approach to Severity Assessment
According to the EAE/ASE recommendations for valve stenosis assessment (Baumgartner H. et al., 2009), grading the severity of stenosis requires an integrative approach using all Doppler and two-dimensional echocardiography data, without relying on a single measurement. Loading conditions affect velocity and pressure gradients, thus these parameters vary in patients with low or high cardiac output. Rhythm disturbances or tachycardia can complicate the assessment of stenosis severity. Echocardiographic measurements in valve stenosis should be interpreted in the clinical context of the specific patient.
Mandatory Parameters in the Report
According to the guidelines for standardization of adult echocardiography reporting (Taub C.C., Stainback R.F. et al., 2025), if stenosis is present, the following should be indicated:
| Parameter | Content |
|---|---|
| Presence and Severity | Presence/absence; grading (mild, moderate, severe) |
| Mechanism | Indicate if possible |
| Quantitative Measurements | Peak velocity, peak gradient |
| Structural Changes (if present) | Thickening, annular or valvular calcification, perforation, masses, presumed etiology |
| Abnormal Leaflet Motion (if present) | Restricted mobility, doming, flail |
Measurement Technique
According to the textbook "Echocardiography: Beginner Level" (Blagodir B.V., 2024), the CWD spectrogram of the trans-tricuspid flow is obtained with an assessment of flow direction and velocity. The normal value of trans-tricuspid flow velocity is 0.3–0.7 m/s. An increase in flow velocity may indicate TS. It is necessary to document TVA (via PHT) and the mean pressure gradient (PGmeanTV).
Specific threshold values (peak velocity, mean gradient, TVA) for grading mild/moderate/severe TS are not provided in the source fragments — [clarify].
Associated Evaluation
The spectrum of tricuspid regurgitation (TRVmax) is assessed separately; the upper limit of normal TRVmax is <2.5 m/s. TRVmax is used to calculate right ventricular systolic pressure (RVSP): in the absence of RVOT obstruction, TRVmax and right atrial pressure (RAP) are used to assess RVSP, with RVSP corresponding to systolic pulmonary artery pressure (RVSP = SPAP).
Frequently asked questions
What quantitative parameters are mandatory for TS?
Peak velocity and peak gradient of trans-tricuspid flow (Taub C.C. et al., 2025). Additionally, TVA via PHT and mean gradient PGmeanTV are documented (Blagodir B.V., 2024).
What is the normal velocity of trans-tricuspid flow?
0.3–0.7 m/s by CWD; an increase in velocity may indicate TS (Blagodir B.V., 2024).
Can TS be graded by a single parameter?
No. EAE/ASE (2009) recommends an integrative approach using all Doppler and 2D data, without relying on a single measurement.
Do loading conditions affect gradients?
Yes. Velocities and gradients vary with low or high cardiac output; rhythm disturbances or tachycardia complicate assessment (EAE/ASE, 2009).
How to assess RV pressure in TS?
In the absence of RVOT obstruction, by TRVmax and RAP; RVSP corresponds to SPAP. The upper limit of normal TRVmax is <2.5 m/s (Blagodir B.V., 2024).