Tricuspid Annular Geometry and Strain After Suture Annuloplasty in Acute Ovine Right Heart Failure

Abstract

Tricuspid valve repair using suture annuloplasty is thought to be more physiologic, but the effect of annular reduction on annular geometry and motion is unknown. We set out to investigate the effect of DeVega suture annuloplasty (DV) on tricuspid annular geometry and dynamics during acute right heart failure (RHF). Ten adult sheep underwent implantation of sonomicrometry crystals around the tricuspid annulus and on the right ventricle; pressure transducers were placed in right ventricle, left ventricle, and right atrium. RHF was induced by a combination of 500 mL volume infusion, posterior descending artery occlusion, and pulmonary artery constriction. Hemodynamic, echocardiographic, and sonomicrometry data were acquired at baseline, with RHF, and after two progressive (8 to 10 mm) DV suture cinches (DV-1, DV-2) during RHF. Annular size, geometry, and dynamics were determined from crystal coordinates. Combination of volume infusion, ischemia, and pulmonary hypertension resulted in acute RHF and significant functional tricuspid regurgitation grade (0.5 ± 0.5 versus 2.7 ± 0.8, p < 0.001). Annular area increased with RHF from 700 ± 98 mm2 to 801 ± 128 mm2 (p < 0.001). DV-1 and DV-2 reduced annular area to 342 ± 88 mm2 and 180 ± 57 mm2 while reducing regurgitation grade to 1.2 ± 0.4 and 0.4 ± 0.5, respectively (all p < 0.001 versus RHF). Tricuspid annular area contraction was 12% ± 7%, 10% ± 6%, and 12% ± 6% for RHF, DV-1, and DV-2, respectively (p= 0.25) and annular height was 4.9 ± 2.0 mm, 5.6 ± 1.4 mm, and 5.5 ± 1.7 mm (p= 0.43). Mean transvalvular gradient was 1.3 ± 0.7 mm Hg and 2.0 ± 1.0 mm Hg with DV-1 and DV-2, respectively. During acute ovine RHF, DeVega annuloplasty successfully treated tricuspid regurgitation and preserved normal tricuspid annular dynamics and geometry. These data may lead to more physiologic tricuspid reparative techniques.