Role of 3D Echocardiography Knowledge-based Reconstruction in ACHD
The main objective of this study is to evaluate the reproducibility and accuracy of TTE-3DKBR in assessing RV volume and EF compared to the reference method of CMR in a group of ACHD patients with known moderate or severe PR after ToF repair.

As part of the validation study, the reproducibility of the TTE-3DKBR in assessing RV volume and EF will also be tested in a group of healthy adult volunteers. Additionally, TTE-3DKBR evaluation will be compared in both groups to the conventional 2D echocardiography measurements used in routine clinical practice, such as tricuspid annular plane systolic excursion (TAPSE), tissue Doppler imaging (TDI), fractional area change (FAC), and global longitudinal strain (GLS).

Another objective of the study is also to evaluate the effects of chronic RV volume overload with an interval of one-year follow-up using TTE-3DKBR and compare it with the conventional non-geometric echocardiography measurements, particularly with GLS.

The study will end when the required number of patients have been enrolled and when the last subject undergoes the research dataset acquisition. The study may be terminated prematurely if it becomes apparent that the recruitment target cannot be met within the projected recruitment phase.
- EligibilityCriteria: Inclusion Criteria:  Group 1 of healthy adult volunteers - Minimum aged of 18 years old without evidence of structural heart disease.  Group 2 of ACHD patients - ACHD patient minimum aged of 18 years old with diagnosis of moderate or severe pulmonary regurgitation after ToF repair.  Exclusion Criteria:  Group 1 of healthy adult volunteers - No informed consent, evidence of structural heart disease.  Group 2 of ACHD patients - No informed consent, pacemaker or defibrillator non-compatible with CMR, limited echocardiographic images for image acquisition, and evidence of moderate or severe right ventricle inflow and/or right ventricle outflow tract obstruction. - HealthyVolunteers: Accepts Healthy Volunteers - Gender: All - MinimumAge: 18 Years - StdAgeList: Adult, Older Adult - StudyPopulation: Group 1 of healthy adult volunteers  Group 2 of ACHD patients with repaired Tetralogy of Fallot and known moderate or severe pulmonary regurgitation - SamplingMethod: Probability Sample