Tricuspid valve


The tricuspid valve ensures that there is no backflow from the right ventricle to the right atrium during systole. The tricuspid valve, as its Latin name suggests, consists of three leaflets: the septal (S), the anterior (A) and posterior (P) leaflets, of which the anterior leaflet is the largest. The tricuspid valve is distinguished not only by the number of valve leaflets as compared to mitral valve, but also by its method of attachment. The mitral valve chordae attach to only two papillary muscle heads where the chordae of tricuspid attach to much more muscle heads and also directly into the interventricular septum. The valve is located slightly more towards the apex as compared to the mitral valve.

Cross section of heart valves
Cross section of heart valves


Quantification of tricuspid regurgitation

Grading the severity of TR
TR severity classes Mild Moderate Severe
Qualitative parameters
Valve morphology Normal or mild abnormal leaflets Moderately abnormal leaflets Severe valve leasions/flail/large coaptation defect/ severe tenting
Colour flow TR jet 𝛼 Small, narrow, central Moderate central Large central or eccentric wall impinging jet of variable size
Flow convergence zone Not visible, transient or small Intermediate in size and duration Large throughout systole
CW signal Faint/partial/parabolic Dense/parabolic or triangular Dense/often triangular with early peaking (peak <2m/s in massive TR)
Semi-quantitative parameters
Hepatic vein flow 𝛽 Systolic dominance Systolic blunting Systolic flow reversal
Tricuspid inflow A-wave dominant Variable E-wave dominant (≥ 1m/s) 𝜀
PISA radius (mm) 𝛾 ≤5 6-9 >9
VC width (mm) 𝛼,𝛿 <3 3-6,9 >7
3D VC area or EROA (mm²)     75-94
Quantitative parameters
EROA (mm²) <20 20-39 ≧40
R Vol (mL) <30 30-44 ≧45
RF (%) ≦15 16-49 ≧50
Structural parameters
RV, RA, IVC size 𝜁 Usually normal Normal or mild dilation Usually dilated

CW, continuous wave; EROA, effective regurgitant orifice area; RA, right atrium; RV right ventricle; TR, tricuspid regurgitation; RF, regurgitant fraction; R Vol regurgitant volume; VC, vena contracta.
𝛼 At Nyquist limit of 50-60 cm/s.
𝛽 Unless other reasons, of systolic blunting (Atrial fibrillation, elevated RA pressure).
𝛾 Baseline Nyquist liit shift of 28cm/s.
𝛿 When VC width is assessed as an average ofmeasurements performed biplane the treshold value for severe TR is >9mm.
𝜀 In the absence of other causes of elevated LA pressure and of mitral stenosis.
𝜁 Unless for other reasons, the RA and RV size and VCI are usually normal in patients with mild TR, An end-systolic RV eccentricity index >2 is in favour of severe TR. In acute severe TR, the RV size is often normal. In chronic severe TR, the RV is classically dilated. Accepted cut-off values for non-significant right-sided chambers enlagement (measurements obtained from the apical four-chamber view): mid RV dimension ≤33mm, RV end-diastolic area ≤28cm², RV end-systolic area ≤16cm², RV fractional area change >32%, maximal 2D RA volume ≤33mL/m². An IVC diameter <21mm in considered normal. The IVC is dilated when the diameter is >25mm.

Echocardiographic criteria for the definition of severe tricuspid valve regurgitation: an integrative approuch.

Parameter Criteria
Valve morphology Abnormal/flail/large coaptation defect
Colour flow regurgitant jet Very large central jet or eccentric wall impinging jet *
CW signal of regurgitant jet Dense/triangular with early peaking (peak <2 m/s in massive TR)
Vena contracta width (mm) ≥ 7 *
Upstream vein flow Systolic hepatic vein flow reversal
Inflow E-wave dominant ≥ 1 m/s **
PISA radius (mm) > 9 ***
EROA (mm²) ≥ 40
Regugitant volume (mL/beat) ≥ 45
Enlargement of cardiac chamber/vessels RV, RA, IVC

* At Nyquist limit of 50-60 cm/s.
** In the absence of other causes of elevated LA pressure
*** Baseline Nyquist limit shift of 28 cm/s.

Outcome-based cut-off values for the quantitative parameters used to grade tricuspid regurgitation severity by Dopplerechocardiography.    
Variable Low risk Intermediate risk High risk    
VC (mm) <3 3 - 6 >6    
EROA (cm²) <0.15 0.15 - 0.30 >0.30    
RegVol (ml) <15 15 - 30 >30    
RegFR (%) <25 25 - 45 >45    
EROA, effective regurgitant orifice area; RegFr, regurgitant fraction; RegVol, regurgitant volume; VCavg, vena contracta width.    
Eur Heart J Cardiovasc Imaging (2021) 22, 155-165    
Proposed expansion of the ‘Severe’ grade          
Variable Mild Moderate Severe Massive Torrential
VC (mm) <3 3 - 6.9 7 - 13 14 - 20 ≥21
EROA (cm²) <0.20 0.20 - 0.39 0.40 - 0.59 0.60 - 0.79 ≥80
3D VCA or quantitative EROAa (cm²)*     0.75 - 0.94 0.95 - 1.14 ≥1.15
VC, vena contracta; EROA, effective regurgitant orifice area; 3D VCA, three-dimensional vena contracta area.
*3D VCA and quantitative Doppler EROA cut-offs may be larger than PISA EROA.
Eur Heart J Cardiovasc Imaging (2017) 18, 1342–1343

TR vena contracta
TR vena contracta

Causes of tricuspid regurgitation

Functional TR Secundary TR
Disorders of the right ventricle: RV infarction, dilated cardiomyopathy Ebstein anomaly
Secondary to pulmonary hypertension, for example: cor pulmonale, pulmonary embolism, or primary. Infective Endocarditis
Mitral stenosis or mitral regurgitation Trauma
Left-right shunt, such as an atrial septal defect or a ventricular septal defect Rheumatic fever
Eisenmenger syndrome (rare) Carcinoid
Pulmonary stenosis Papillary muscle disorders
Hyperthyroidism Connective tissue diseases such as Marfan Syndrome.
  Non-infectious endocarditis, such as SLE or rheumatoid arthritis
  Damage from the electrode of a pacemaker or ICD


Tricuspid valve stenosis is usually caused by rheumatic fever which mostly occurs during childhood. The rarely reported second causes of tricuspid valve stenosis include tumour obstruction, carcinoid disease and obstructed tricuspid valve prosthesis.

Quantification of tricuspid stenosis

Parameter Mild Moderate Severe
TVA (cm²)     < 1
PHT (ms)     > 190
PGmean (mmHg)     > 5
VTI (cm)     > 60


The information above comes from Last changed on: 11 September 2023.