Impact of right atrium dimension on adverse outcome after pulmonary valve replacement in repaired Tetralogy of Fallot patients

The hemodynamic impact of residual pulmonary regurgitation (PR) in repaired Tetralogy of Fallot (rTOF) has been well demonstrated. However, markers driving the decision making process to indicate the ideal timing of pulmonary valve replacement (PVR) are still uncertain. Furthermore, very few studies have included the right atrium (RA) dilatation as a preoperative risk factor for post-PVR clinical adverse outcome. The aim of this study was to investigate the impact of pre-PVR right atrial dilation on adverse outcomes in rTOF. We retrospectively reviewed from our CMR database all rTOF patients who underwent CMR study before and after PVR. Detailed clinical and surgical history were collected, in addition to imaging data. The composite primary and secondary post-PVR end points were also recorded. The study cohort consisted of 41 patients (mean age at PVR repair 27.4 ± 10 years). As expected, end-diastolic and end-systolic right ventricle (RV) volumes significantly decreased after PVR (p < 0.001). The RV reverse remodeling, defined by ΔRVEDVi and ΔRVESVi, was associated with both pre-PVR RVEDVi and RVESVi. The higher the pre-PVR RV volumes, more the RV reverse remodeling will be obtained post-surgery. Patients who experienced an adverse outcome were older at pre-PVR, they had a higher Nt-ProBNP, worse VO2/kg/min, more significant tricuspid regurgitation and more dilated RA. The association with the RA dilatation persists and becomes even more significant if we exclude patients who had tricuspid repair beside RVOT surgical reconstruction. Besides RV volumes and function, RA dimensions may play a pivotal role in the decision making of TOF patients.