Functional Anatomy of Tricuspid Regurgitation in Patients with Systemic Right Ventricles

Abstract

Although the functional anatomy of mitral regurgitation has been thoroughly studied and is strongly predictive of postoperative outcome, the functional anatomy of tricuspid regurgitation (TR) in patients with systemic right ventricles has not been described. We measured the indices of tricuspid valve deformation, right ventricular remodeling and function, and brain natriuretic peptide (BNP) concentrations in a series of 42 patients (mean age 20.8 +/- 3.7 years) with systemic right ventricles after atrial switch for complete transposition of the great arteries. TR was present in 34 patients. It was associated with predominant annular dilatation in 5 patients (14.7%), valvular prolapse in 14 patients (41.1%), and systolic leaflet tethering in 15 patients (44.1%). Compared with patients with valve prolapse, patients with leaflet tethering had greater end-systolic right ventricular cavity area (21.1 +/- 3.6 cm(2) vs 27.3 +/- 7.9 cm(2); P < .05), lower right ventricular fractional area change (0.40 +/- 0.09 vs 0.34 +/- 0.09, P < .05), and higher BNP levels (14.6 +/- 13.5 pg/mL vs 25 +/- 24.3 pg/mL, P < .05). Intermediate values were observed in patients with annular dilatation (23.9 +/- 5.6 cm(2); 0.37 +/- 0.05 pg/mL and 19.0 +/- 0.07 pg/mL, respectively). Three distinct types of TR, caused by predominant annular dilatation, valve prolapse, and valve tethering, were apparent in patients with systemic right ventricles. They were associated with diverse severity of right ventricular dysfunction and BNP activation. Further studies are needed to assess the impact of variable functional anatomy of the systemic tricuspid valve on the outcome of medical and surgical therapies.