Long-term assessment of clinical outcomes and disease progression in patients with corrected Tetralogy of Fallot.

OBJECTIVE: Understanding changes of right ventricular (RV) geometry and function in repaired Tetralogy of Fallot (rToF) patients can improve decision-making for pulmonary valve replacement. Therefore, we aimed to assess the magnitude and clinical correlations of RV changes in rToF patients. PATIENTS AND METHODS: Clinical and MRI data of rToF patients who underwent repeated cardiac magnetic resonance imaging (MRI) at two centers between December 2003 and September 2020 were analyzed together with anatomical factors, including RV outflow tract obstruction, pulmonary artery branch stenosis, and tricuspid regurgitation. Adverse cardiac events and/or NYHA class worsening were documented and correlated with MRI changes. QRS length was reported at each MRI. RESULTS: Two-hundred-and-nineteen rToF patients (53% males, aged 20.2 ± 10.1 years) were enrolled. An increase of ventricular dimensions, except LVEDVi, and worsening of right and left ejection fractions were found over an average period of 5 years of follow-up. These changes were statistically significant but within 10% of the initial value. No significant changes were reported on a year-to-year basis, except in a small group of patients (6%) in whom no predictive factors were identified. Despite similar RV dimensions at the first examination, younger patients had a higher RV ejection fraction and a different annual rate of change of ventricular dimensions compared to older ones. Patients with arrhythmias (20%) were more frequently older and had larger RV dimensions but showed no significant correlations with MRI changes/years. CONCLUSIONS:  Changes in RV dimensions and function occur rarely and very slowly in rToF patients. A small percentage of patients experience a significant worsening in a short time interval without any recognized risk factors. Arrhythmias appear to occur in a small percentage of cases in the late follow-up.

The role of 3D imaging in the follow-up of patients with repaired tetralogy of Fallot.

OBJECTIVE: The patients with repaired Tetralogy of Fallot (rToF) are a growing population due to the improvement of surgical management in neonatal age. However, the significant pulmonary regurgitation, consequent to the repair, is the most frequent sequelae and leads to a progressive right ventricle dilation over time. The latter, in turn, is responsible for the possible dysfunction of right and/or left ventricle and an increased risk of dangerous ventricular arrhythmias. Therefore, right ventricle monitoring is necessary for rToF patients and a 3D method is required due to its three anatomical and functional subunits. Magnetic resonance imaging (MRI) has become the 3D modality of choice in the evaluation of both cardiac anatomy and ventricular volumes in rToF patients since it is able to evaluate both the pathophysiology and anatomy, it is free of radiation and, when strictly necessary, it uses a non-iodinated contrast agent. Cardiac CT should be considered in the evaluation of the sequelae in rToF only in selected cases, given that it implies a radiation dose and iodinated contrast, in addition to not evaluating the pathophysiology as MRI.