Normal Range for Tricuspid Regurgitant Velocity (TRV) Max
The normal TRV max is less than 2.5 m/s, with values ≥2.5 m/s considered elevated and associated with increased mortality risk. 1
Specific Normal Values
- TRV < 2.5 m/s: Normal range 1
- TRV 2.5-2.9 m/s: Borderline elevated, associated with 4-5 fold increased mortality risk 1, 2
- TRV ≥ 3.0 m/s: Significantly elevated, associated with 10-fold increased mortality risk 1
Clinical Context and Interpretation
Important caveat: TRV velocity alone does not indicate severity of tricuspid regurgitation. 1 In fact, massive TR often presents with low jet velocity (<2 m/s) due to near equalization of right ventricular and right atrial pressures. 1 Conversely, mild TR with severe pulmonary hypertension can produce high-velocity jets. 1
When Assessing TR Severity (Not Pulmonary Pressure)
The continuous wave Doppler signal characteristics matter more than velocity: 1
- Mild TR: Faint, parabolic signal 1
- Moderate TR: Dense, parabolic signal 1
- Severe TR: Dense, triangular with early peaking (peak < 2 m/s in massive TR) 1
For Prosthetic Tricuspid Valves
Different thresholds apply: 1
- Normal: Peak early diastolic velocity < 1.9-2.0 m/s 1
- Possible obstruction: Peak velocity ≥ 1.9-2.0 m/s with mean gradient ≥ 6-9 mmHg 1
Measurement Technique Requirements
Critical technical points to ensure accurate measurement: 1
- Measure during stable clinical state (>4 weeks after acute chest syndrome, >2 weeks after vaso-occlusive crisis or transfusion) 1
- Average minimum 5 cardiac cycles during end-expiration or quiet respiration 1
- Use multiple transducer positions and off-axis views to align ultrasound beam parallel to flow 1
- TRV is measurable in only 39-86% of patients; absence does not rule out elevated pulmonary pressure 3
Mortality Risk Stratification
Age-specific mortality rates based on TRV in adults: 1
- TRV < 2.5 m/s: ~2% mortality 1
- TRV 2.5-2.9 m/s: ~10% mortality (4.4-5.9 fold increased risk) 1, 2
- TRV ≥ 3.0 m/s: ~20% mortality (10.6 fold increased risk) 1
Pediatric populations show lower prevalence (16-19% with TRV ≥2.5 m/s) and TRV does not independently predict short-term morbidity in children. 4
Common Pitfalls to Avoid
- Do not use TRV velocity alone to grade TR severity—it reflects RV-RA pressure gradient, not regurgitant volume 1
- Do not measure during acute illness—TRV transiently increases during vaso-occlusive crisis or acute chest syndrome 1
- Do not assume elevated TRV equals pulmonary hypertension—only 33-46% of patients with elevated TRV have catheterization-confirmed pulmonary hypertension 5, 4
- Do not ignore respiratory variation—marked variation with inspiration suggests elevated right atrial pressure 1
- Do not rely on single measurement—TRV measurements may be unreliable with severe TR (underestimates pressure) or tubular stenosis (overestimates pressure) 3