Real-Time 3-Dimensional Echocardiography Provides New Insight Into Mechanisms of Tricuspid Valve Regurgitation in Patients With Hypoplastic Left Heart Syndrome

Abstract

Background-Tricuspid regurgitation in hypoplastic left heart syndrome has an impact on outcome, but its mechanisms remain unclear. Methods and Results-Real-time 3-dimensional echocardiography was performed in 35 patients with hypoplastic left heart syndrome (age, 1 month to 10 years; 10 after first-stage Norwood, 12 after superior cavopulmonary shunt, 13 after Fontan). From the 3-dimensional data set, we marked the annulus in systole and diastole. At mid systole, we marked the location of the papillary muscle tip and point of chordal attachment to the leaflet. We traced the surfaces of the tricuspid valve leaflets and measured the volume of leaflet prolapse, tethering, annular and septal leaflet areas, and papillary muscle position. Seventeen patients had moderate tricuspid regurgitation (prolapse, 7; tethered leaflets, 7) and 18 mild (prolapse, 0; tethered leaflets, 7). Multiple linear regression analysis revealed that moderate tricuspid regurgitation is associated with leaflet tethering and prolapse; that in hypoplastic left heart syndrome with tethered leaflets, the papillary muscle is displaced laterally and the tricuspid annulus is more planar; and that enlargement of the annulus at mid systole, small septal leaflet area, and age affect the degree of prolapse. Conclusion-In hypoplastic left heart syndrome, moderate tricuspid regurgitation may be associated with increasing age, geometrical changes of the annulus, leaflet prolapse, lateral papillary muscle displacement, and subsequent leaflet tethering, as well as a smaller septal leaflet.

Right Versus Left Ventricular Failure

“…In hypoplastic left heart syndrome, for example, the absence of a developed LV may alter tricuspid valve annular configuration and worsen tricuspid regurgitation, an important risk factor for adverse outcomes in this population. 105 Likewise, a larger interventricular septum may increase the risk for death or transplantation in this population. 106 This may be yet another manifestation of the effects of ventricular-ventricular interactions on RV function.…”

Tricuspid Regurgitation in Hypoplastic Left Heart Syndrome

“…[8][9][10] Quantitative 3DE permits evaluation of the spatial relationships between the TV annulus, leaflets, and the supporting apparatus by measurement of tethering and prolapse volumes, leaflet and annular areas, and PM angles. 4,11 We have reported the use of quantitative 3DE to assess mechanisms of TR and demonstrated that this technique is able to detect areas of TV tethering and prolapse in HLHS. 4 Previous studies have evaluated mechanisms for TR in HLHS at or beyond the time of the second-stage palliation; however, there is a paucity of literature on TV function before Background-Our purpose was to test the following hypotheses: (1) patients with hypoplastic left heart syndrome who develop significant tricuspid regurgitation (TR) or require tricuspid valve (TV) surgery in the medium term have detectable TV abnormalities by 3-dimensional echocardiography (3DE) prestage 1 palliation and (2) TR is associated with reduced survival and increased TV intervention.…”

“…This proprietary software was used to develop 3D models of the TV and its apparatus for analysis as described previously. 4,11 Briefly, by using the extracted x, y, and z spatial coordinates, the software defined 2 separate surfaces, one surface that is fit to the TV leaflets and one that is fit to the annulus. The coordinate system was rotated and translated so that the origin (0, 0, 0) is at the center of the annulus and the z axis is perpendicular to the best-fit plane to the annulus, as shown in Figure 1A and 1C, for 2 representative subjects.…”

“…The annular bending angle was measured using a previously reported method, illustrated in Figure 1. 4 Briefly, the annulus was divided into anterior and posterior sections, as defined by the bending points, identified in the figure near the midseptum. The annular points in each of these sections were fit with a plane (non-negative least squares), from which the bending angle was measured as the angle between the normal lines for each plane.…”

“…4,11 We have reported the use of quantitative 3DE to assess mechanisms of TR and demonstrated that this technique is able to detect areas of TV tethering and prolapse in HLHS. 4 Previous studies have evaluated mechanisms for TR in HLHS at or beyond the time of the second-stage palliation; however, there is a paucity of literature on TV function before Background-Our purpose was to test the following hypotheses: (1) patients with hypoplastic left heart syndrome who develop significant tricuspid regurgitation (TR) or require tricuspid valve (TV) surgery in the medium term have detectable TV abnormalities by 3-dimensional echocardiography (3DE) prestage 1 palliation and (2) TR is associated with reduced survival and increased TV intervention. Methods and Results-Infants were prospectively studied with 3DE and 2DE prestage 1 and followed up for the end points of TR, TV surgery, transplantation, or death.…”