Developing Insights Regarding Tricuspid Valve Regurgitation: Morphology, Assessment of Severity, and the Need for a Novel Grading Scheme

Figures

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  Figure 1. Autopsy heart. The figure illustrates the tricuspid apparatus and the right ventricle. The tricuspid valve is classically described as having a trileaflet morphology. The septal leaflet, outlined by the color yellow, is adjacent to the interventricular septum and is attached directly through the RV wall or through its papillary muscle by multiple chordae tendineae in a parachute-like fashion. The red dotted line outlines the anterior leaflet contour which is supported by the anterior papillary muscle. The posterior leaflet is outlined by the color blue and is adjacent to the right ventricle wall. The posterior papillary muscle is often bifid or trifid and provides chordal support to the posterior and septal leaflets. This patient has an ICD lead. Abbreviations: ICD, implantable cardioverter defibrillator (arrow); RV, right ventricle.

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  Figure 2. Etiologies of tricuspid valve dysfunction. Myxomatous degeneration of the tricuspid valve leading to prolapse shown by 3D from the right atrium perspective (a1) and by 2D TTE from the RV-focused view (a2); Impingement of a cardiac implantable electronic device in the septal leaflet of the TV seen by 3D from the ventricle (b1) and atrial orientation (b2); 2D TTE RV-focused view showing a mass in TV leaflets (c1), and 3D from the right atrium perspective of the TV, revealing a vegetation attached to the anterior leaflet (c2); Ruptured septal leaflet with flail chordae seen on 2D TTE (d1, red arrow), resulting in severe TR with eccentric jet (d2) and 3D from the right atrial orientation (d3) demonstrating the leaflets and the flail chordae (red arrow); From the ventricle perspective is illustrated a quadricuspid (e) and bicuspid (f) valve; At midsystole, on the ventricle perspective, using the technique of transillumination, it is possible to visualize the malcoaptation of the TV leaflets (g). See text for detailed information. Abbreviations: 2D, 2-dimensional; 3D, 3-dimensional; A, anterior; P, posterior; RV, right ventricle; S, septal; TR, tricuspid regurgitation; TTE,…

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  Figure 3. 2D transthoracic targeting image of the tricuspid valve. Using additional views and landmarks is possible to identify the tricuspid leaflets. The leaflets closest to the aorta are the anterior or the septal leaflets (never the posterior), the leaflet closest to the free wall is the posterior or the anterior (never the septal), and finally, the septal leaflet is the closest to the septum. In the RV inflow view, the yellow dots outline the septal leaflet, closest to the coronary sinus and the septum. The red dots mark the anterior leaflet closest to the transducer (a). When the RV apical view intersected the LVOT, the combination anterior (red dots) and septal leaflet (yellow dots) are present (b). However, when the coronary sinus is intersected, the posterior (blue dots) and septal (yellow dots) are seen (c). In the parasternal short axis view, the anterior leaflet is present if only a single leaflet is seen (d). In the subcostal short-axis view, the septal leaflet (yellow dots) is close to the septum, the posterior leaflet (blue dots) is closest to the liver, and lastly, the anterior leaflet is adjacent to the aortic valve (e). Abbreviations: A, anterior; CS, coronary sinus; IVS,…

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  Figure 4. Important TEE views during TV percutaneous interventions: (a) Mid-esophageal bicaval view, wherein the right-side chambers, the posterior and anterior TV leaflets and its landmarks are appreciated. This view is particularly important owing to the optimal 3D acquisition and TR assessment due to ideal beam and coaxial flow alignment and also to guide the catheter through the IVS and toward the TV during intervention; Transgastric biplane image: (b) In the short-axis view, it is possible to visualize all the leaflets simultaneously, (c) to assess the coaptation gap, the regurgitant orifice, and the orientation of the jet. The biplane technique can aid in the appraisal. (d) In the left bottom image, a Clip can be seen grasping the septal and posterior leaflets. Abbreviations: A, anterior; IVC, inferior vena cava; IVS, interventricular septum; LA, left atrium; LV, left ventricle; LVOT, left ventricular outflow tract; P, posterior; RA, right atrium; RV, right ventricle; RVOT, right ventricle outflow tract; S, septal; SVC, superior vena cava; TR, tricuspid regurgitation; TTE, transthoracic echocardiography; TV, tricuspid valve.

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  Figure 5. Multiparametric approach using quantitative and semiquantitative methods for grading TR. VC width (right image) is measured in midsystole, using zoom mode, with proper beam-flow orientation and Nyquist limit ranging between 35 and 60 cm/s, on parasternal RV inflow and apical 4-chamber views. The proximal isovelocity surface area [PISA] method calculates the radius of the convergence flow area. The radius must be measured from the top of the shell until the VC, after adjustment of the Nyquist limit baseline between 28 and 40 cm/s, and the PISA will be estimated through the formula presented above. The angle correction can be made by multiplying the Q by alpha/180. From the PISA and the TR regurgitant flow, quantitative techniques such as effective regurgitant orifice area (EROA) and the regurgitant volumes (Rvol) are derived. Abbreviations: RV, right ventricle; TR, tricuspid regurgitation; VC, vena contracta.

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  Figure 6. Multiplane imaging of the TR. The 3D color Doppler image aligns the green and red planes to image the vena contracta area in the blue plane. Abbreviations: 3D, 3-dimensional; TR, tricuspid regurgitation.

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  Figure 7. Supportive signs of severe TR. Systolic flow reversal in the hepatic veins detected by pulsed wave (PW) spectral Doppler from a subcostal view (a); Dense and triangular continuous wave (CW) spectral shape of TR jet with low (<2.5 m/s) and early peaking of the velocity representing the imminent equalization of the right ventricle and atrial pressure (b). Abbreviation: TR, tricuspid regurgitation.

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  Figure 8. Measurements of the tricuspid annulus using different echocardiogram modalities. Two-dimensional measurements of the tricuspid annulus from transthoracic RV inflow view (a) and from the transesophageal midesophageal 4-chamber view (b) in which the annulus was measured from the hinge point to the hinge point at end-diastole (yellow lines). 3D full volume of RV-focused view derived from transthoracic echocardiogram was sliced and oriented (c and d) to obtain a planimetry of the tricuspid annulus. The yellow dotted line outlines the TA area (e), the red line represents the long-axis diameter (LA), and the green line represents the short-axis diameter (SA) measurement. Abbreviations: RV, right ventricle; TA, tricuspid annulus.

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  Figure 9. Right ventricular diameter and function metrics attained from the RVapical-focusedview: (a) RV basal diameter (a), RV mid diameter (b), and RV length (c); (b) TAPSE; (c) RV free wall and global longitudinal strain. (d) Right atrial phasic function obtained through 2D speckle tracking; (e) When the QRS is used as the timing reference point, the phasic curve starts with the peak positive longitudinal atrial strain corresponding to the reservoir function (RASr_ED), followed by the early diastolic strain waves representing the conduit phase (RAScd_ED) and finally the late diastolic strain wave expressing the booster pump. Abbreviations: 2D, 2-dimensional; RV, right ventricle; TAPSE, tricuspid annular plane systolic excursion.

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  Figure 10. Right ventricle 3D analysis using dedicated software. After the TTE full-volume acquisition, the right ventricle planes were aligned and the TV annulus was marked, followed by the trace of the endocardial border on the short and long axis to obtain end-diastolic and end-systolic planes. The software estimates volume and function metrics. (RASct_ED). Abbreviations: 3D, 3-dimensional; TTE, transthoracic echocardiography; TV, tricuspid valve.