Tricuspid inflow E-wave velocity for the assessment of severe or greater tricuspid regurgitation: derivation and external validation of threshold values

Aims Current guidelines include tricuspid inflow E-wave (>100 cm/s by pulsed-wave Doppler) as a semiquantitative criterion for diagnosing severe tricuspid regurgitation (TR), despite limited supporting evidence. We assessed its diagnostic performance for identifying severe or greater TR, deriving and externally validating practical thresholds. Methods and results Tricuspid inflow E-wave velocity was measured by pulsed-wave Doppler in consecutive patients with at least mild TR between December 2024 and February 2026. Among 178 patients (77±13 years, 65% women), TR was mild in 44, moderate in 61, severe in 44, massive in 15, and torrential in 14. Mean tricuspid E-wave velocity was 56±16 cm/s and increased with TR severity: 47±8, 50±10, 62±16, 67±13, and 77±21 cm/s for mild, moderate, severe, massive, and torrential TR. Only three patients had E-wave velocity >100 cm/s (one with severe and two with torrential TR). Using multiparametric echocardiographic grading as the reference standard, the >100 cm/s threshold showed 5.5% sensitivity, 100% specificity, and kappa 0.25 for severe or greater TR. As a continuous variable, E-wave velocity discriminated severe or greater TR with an AUC of 0.81. A lower threshold of 52 cm/s yielded 81% sensitivity and 67% specificity, whereas 47 cm/s provided 90% sensitivity and 43% specificity. External validation resulted in 94% sensitivity and 47% specificity. Conclusion The guideline-recommended threshold of >100 cm/s is highly insensitive for detecting severe or greater TR. Lower cut-offs, particularly 47 cm/s, may be useful for screening to trigger a comprehensive multiparametric assessment.