Right Ventricular and Tricuspid Valve Remodeling After Bidirectional Cavopulmonary Anastomosis

Background: There are few investigations of the changes in tricuspid valve (TV) and right ventricular (RV) morphology following bidirectional cavopulmonary anastomosis (BCPA). Methods and Results: The 2-D echocardiograms of 35 children (male, n=23; female, n=12; median age, 6 months; range, 3-10 months) with hypoplastic left heart syndrome, 1 month before and after BCPA performed between 2005 and 2011, were retrospectively reviewed. Patients who underwent TV repair at BCPA were excluded. From the 4-chamber view, the coaptation length, vena contracta width and RV end-diastolic area before and after BCPA were measured and indexed to surface area. The severity of tricuspid regurgitation was graded qualitatively. After BCPA, RV end-diastolic area decreased from 2,951 +/- 584 to 2,580 +/- 591 mm(2)/m(2) (P < 0.001). The coaptation length of the anterior leaflet (8.8 +/- 5.8 vs. 11.0 +/- 6.2 mm/m(2), P=0.0014) and of the septal leaflet (13.5 +/- 5.3 vs. 15.8 +/- 5.4 mm/m(2), P=0.0072) increased after BCPA. The vena contracta width decreased (5.8 +/- 4.9 vs. 4.3 +/- 4.2mm/m(2), P=0.035), although there was no change in tricuspid regurgitation grade after BCPC (1.4 +/- 0.7 vs. 1.4 +/- 0.9, P=0.234). Conclusions: In children with hypoplastic left heart syndrome after BC PA, the coaptation length of the anterior and septal leaflets of the TV improved concomitantly with vena contracta width and RV end-diastolic area despite unchanged tricuspid regurgitation grade. This suggests that favorable RV and TV remodeling accompanies the reduction in RV volume load following BCPA.