The vena contracta width correlates more closely with the severity of TR than does the color jet area2 and is often measured in the midesophageal right ventricular inflow-outflow view. The TR velocity to calculate the PASP can be measured in that same window. Measurement of the RA dimensions is usually done in the ME4C at end systole. RV size is frequently evaluated semiquantitatively. Increased chamber size is expected in significant TR but is a nonspecific sign. Reversal of systolic hepatic vein flow, although nonspecific, is consistent with severe TR and is indicative of increased RA pressure in a patient in sinus rhythm.
The presence of TR in a structurally normal valve is usually caused by annular dilation resulting from pulmonary hypertension.3 Referred to as functional TR, it is often secondary to left-sided lesions such as MR.4 The TA is frequently measured in the ME4C during mid-diastole (Fig. 3C), because there are reference values for that dimension. Note that the TA dimension during diastole will be larger than the systolic TA dimension.
Surgical intervention for TR alone is uncommon and is usually done as an adjunctive procedure, especially during MV surgery.1,3 Current guidelines recommend repair of severe TR when undergoing MV surgery; usually tricuspid annuloplasty is sufficient (Video 3, see Supplemental Digital Content 3, http://links.lww.com/AA/A18, midesophageal four-chamber view after suture annuloplasty of the tricuspid valve with no evidence of regurgitation; RA = right atrium, LA = left atrium, RV = right ventricle, LV = left ventricle). Repair is also recommended for even mild TR in the presence of a dilated TA or pulmonary hypertension, because annular dilation appears to be a continuing process that worsens over time.3 Improvement or resolution of TR after MV surgery is unpredictable. Decreasing the pulmonary hypertension with MV surgery may decrease the TR provided that reverse remodeling of the dilated TA and RV occurs.4
In summary, presented with a dilated TA and TR at the time of MV surgery, current literature supports TV repair regardless of the degree of TR.4,6 For surgical decision-making purposes, some echocardiographers and surgeons consider a TA diameter >21 mm/M2 in the ME4C to be dilated enough to warrant consideration of annuloplasty.5,6
1. Zoghbi WA, Sarano ME, Foster E, Grayburn PA, Kraft CD, Levine RA, Nihoyannopoulos P, Otto CM, Quinones M, Rakowski H, Stewart WJ, Waggoner A, Weissman NJ. Recommendations for evaluation of the severity of native valve regurgitation with 2D and Doppler echocardiography. J Am Soc Echocardiogr 2003;16:777–802
2. Tribouilloy CM, Sarano ME, Bailey KR, Tajik AJ, Seward JB. Quantification of tricuspid regurgitation by measuring the width of the vena contracta with doppler color flow imaging: a clinical study. J Am Coll Cardiol 2000;36:472–8
3. Bonow RO, Carabello BA, Chatterjee K, de Leon AC, Faxon DP, Freed MD, Goosch WH, Lytle BW, Nishimura RA, O'Gara PT, O'Rourke RA, Otto CM, Shah PM, Shanewise JS. ACC/AHA 2006 guidelines for the management of patients with valvular heart disease. J Am Coll Cardiol 2006;48:e1–148
4. Dreyfus GD, Corbi PJ, Chan J, Bahrami T. Secondary tricuspid regurgitation or dilatation: which should be the criteria for surgical repair? Ann Thorac Surg 2005;79:127–32
5. Maslow AD, Schwartz C, Singh AK. Assessment of the tricuspid valve: a comparison of four transesophageal windows. J Cardiothorac Vasc Anesth 2004;18:719–24
6. Colombo T, Russo C, Ciliberto GR, Lanfranconi M, Bruschi G, Agati S, Vitali E. Tricuspid regurgitation secondary to mitral valve disease, tricuspid annulus function as a guide to tricuspid valve repair. Cardiovasc Surg 2001;9:369–77
Clinician's Key Teaching Points
By Nikolaos J. Skubas, MD, Roman M. Sniecinski, MD, and Martin J. London, MD
Functional tricuspid regurgitation exists with structurally normal leaflets and is usually caused by annular dilatation. This is often secondary to left-sided lesions such as mitral regurgitation.
The tricuspid annulus should be measured in mid-diastole using the midesophageal 4-chamber view.
The severity of tricuspid regurgitation can be evaluated using the width of the vena contracta, which is the narrowest “neck” of the jet as it crosses the tricuspid annulus plane. In severe tricuspid regurgitation the vena contracta is >7 mm when the Nyquist limit is 50–60 cm/s.
Other echocardiographic parameters suggestive of severe tricuspid regurgitation include reversal of hepatic venous flow (imaged with Doppler in a modified midesophageal 4-chamber view with a rightward turn of the probe), an enlarged right atrium (minor axis >4.5 cm), and leftward shift of the interatrial septum.
A tricuspid annulus >21 mm/m2 (measured in mid-diastole in the midesophageal 4-chamber view) usually warrants tricuspid annuloplasty, irrespective of tricuspid regurgitation severity.