Abstract
OBJECTIVE: Surgical annuloplasty for functional tricuspid regurgitation (FTR) is on the rise and can be performed in several ways with varied outcomes. In this study, we sought to compare the hemodynamic outcomes of tricuspid annuloplasty performed with a commercially available annuloplasty ring (tricuspid valve annuloplasty [TVA]) compared with focal suture annuloplasty (Hetzer) in an experimental FTR model. METHODS: An ex vivo FTR model was developed by inducing right ventricular dilatation by acute afterload elevation, causing severe tricuspid valve tethering and annular dilatation, leading to regurgitation. Ten porcine hearts in which FTR was induced underwent TVA with a 26-mm Edwards MC3 ring and Hetzer annuloplasty with a pledgeted suture cinching the anteroposterior and septal annulus. FTR was measured before after each repair, and tenting geometry, valve kinematics, and subvalvular geometry were measured with echocardiography. RESULTS: At baseline, none of the hearts had FTR, but upon afterload elevation an FTR volume of 17.7 ± 9.2 mL (26.38 ± 17.47% regurgitant fraction) was measured (P < .0001). TVA reduced regurgitation by 50% and Hetzer annuloplasty by 56% , respectively, but both left persistent FTR. Anteroseptal tenting area was 279.0 ± 158.9 mm(2) before repair and decreased significantly to 147.2 ± 134.8 mm(2) (P = .0195) with Hetzer but not with TVA. Posteroseptal tenting area was 425.1 ± 169.2 mm(2) before repair and was significantly reduced by both techniques (TVA: 200.3 ± 102.9 mm(2) [P = .0012]; Hetzer: 237.6 ± 127.6 mm(2) [P = .0270]). CONCLUSIONS: Tricuspid annuloplasty with a ring or a focal suture can reduce FTR but not eliminate it. Annular approaches did not relieve tricuspid valve tethering and reduced leaflet mobility persisted. Either subannular repairs or judicious use of valve replacement may be necessary.