Tricuspid annular systolic velocity
RV S′ (RVSm) · Pulsed tissue Doppler, RV-focused apical 4-chamber, sample volume on the lateral tricuspid annulus
Normal range & thresholds
2025 ASE graded severity:
The older single threshold was <9.5–10 cm/s abnormal. RV free-wall longitudinal strain, the parameter the guideline now emphasises most, is abnormal when the magnitude is less than 20% in men and 21% in women.[3,76]
| RV S′ | Grade |
|---|---|
| >9.5 cm/s | Normal |
| 7.2–9.5 cm/s | Mildly reduced |
| >5.0–7.2 cm/s | Moderately reduced |
| <5.0 cm/s | Severely reduced |
Pathophysiology
The same longitudinal physiology as TAPSE, expressed as a velocity rather than a displacement, and sharing all of its virtues and vices: quick, reproducible, single-point, angle-dependent and load-dependent. It is typically the first RV index to fall in chronic pressure overload and the most sensitive of the simple measures, which is why the guideline pairs it with FAC and strain rather than choosing between them.[3]
Raised by
- Hyperdynamic states, sepsis, anaemia, thyrotoxicosis, exercise, inotropes
- Severe tricuspid regurgitation (falsely reassuring)
- Youth and athletic training
Lowered by
- Pulmonary hypertension; chronic lung disease; acute pulmonary embolism
- RV infarction, ARVC, sarcoid, amyloid, myocarditis
- Post-cardiac surgery — falls with TAPSE after pericardiotomy and stays low
- Advanced biventricular failure; post-LVAD RV failure
- Constrictive pericarditis; severe tricuspid stenosis; pacing leads across the annulus
Technique & pitfalls
- Angle of insonation <20° to annular motion; the RV-focused view usually gives better alignment for the tricuspid annulus than the standard 4-chamber view.
- Sample volume 5–10 mm on the lateral tricuspid annulus (not the septal annulus, which reflects biventricular mechanics).
- Sweep 50–100 mm/s; measure the peak of the systolic wave, excluding the isovolumic contraction spike.
- Report with TAPSE, FAC and strain — never in isolation.[3]
- In congenital and post-operative hearts, and in a systemic RV, none of these normal ranges applies.
Pseudo-change & artefact
- Angle error — underestimates.
- Sample volume drifting off the annulus during the cardiac cycle.
- Cardiac translation and respiratory motion — overestimate.
- Severe tricuspid regurgitation — overestimate.
- Post-pericardiotomy state — a real but non-pathological fall.
- Load: falls with hypovolaemia and rises with volume loading.
- Blind to regional and outflow-tract dysfunction.
Treatment thresholds
- No stand-alone treatment threshold. Its role is to contribute to the integrated judgement of RV systolic function, which then feeds the decisions listed under TAPSE and FAC.
- It defines RV dysfunction for pulmonary hypertension risk tables, for tricuspid intervention eligibility, for acute pulmonary embolism risk stratification, and for LVAD/transplant candidacy.[6,8,11]
- It is a component of the RV myocardial performance (Tei) index.[19]
Next step
- Next: RV free-wall longitudinal strain — the 2025 guideline’s preferred sensitive measure, abnormal at <20% (men) / <21% (women) in magnitude, and prognostically superior to TAPSE and FAC.[3,76]
- Then: 3D RV ejection fraction, then CMR.
- Then: the aetiological work-up as for TAPSE — pulmonary pressures, PVR, thromboembolic imaging, right heart catheterisation.
Drugs
- As for TAPSE and FAC: treat the load and the disease.
- Rises acutely with inotropes and with any hyperdynamic state, without implying recovery.
- Falls with beta-blockade and with excessive diuresis.
Reversibility
Parallels TAPSE. Reversible in acute pulmonary embolism, RV infarction, sepsis and reversible pressure overload; largely fixed in ARVC, established fibrosis, and after pericardiotomy.[3]