Determinants of Aerobic Capacity After Tricuspid Valve Replacement in Congenitally Corrected Transposition of Great Arteries

Systemic tricuspid regurgitation and impaired aerobic capacity are common in adults with congenitally corrected transposition of great arteries (cc-TGA), but it is unknown whether systemic tricuspid valve replacement (sTVR) is associated with improvement in aerobic capacity. The purpose of this study was to determine whether sTVR was associated with postoperative improvement in aerobic capacity as measured by peak oxygen consumption (VO2). This is a retrospective cohort study of adults with cc-TGA and ≥moderate tricuspid regurgitation that underwent sTVR and exercise test pre- and post-sTVR (2003-2019). We selected a propensity-matched control group of patients with cc-TGA and ≥moderate tricuspid regurgitation that did not undergo sTVR between exercise tests. Improvement in aerobic capacity was calculated as the difference between baseline and follow-up exercise tests. The study comprised 48 patients in each group, and both groups had similar peak VO2 at baseline. Compared to the baseline exercise test, the sTVR group had more improvement in peak VO2 (6 ± 4% vs −8 ± 3%-predicted, P = 0.001), and the factors associated with postoperative improvement in peak VO2 were baseline systolic blood pressure (<120 mm Hg), systemic right ventricular global longitudinal strain (<−16%), and preoperative peak VO2 (>60%-predicted). There was an improvement in aerobic capacity after sTVR in patients with cc-TGA and severe tricuspid regurgitation. The determinants of improvement in aerobic capacity were baseline systolic blood pressure, systemic right ventricular global longitudinal strain, and preoperative peak VO2. Further studies are required to determine whether strict blood pressure control and optimal timing of sTVR based on these indices would result in improved clinical outcomes in this population.