Background The myocardial adaptive mechanism in patients with repaired tetralogy of Fallot (rTOF) is less understood. We aimed to investigate biventricular myocardial adaptive remodeling in rTOF patients. Methods We recruited 32 rTOF patients and 38 age-and sex-matched normal controls. The pulmonary stenosis of rTOF patients was measured using catheterized pressure gradient between right ventricle (RV) and pulmonary artery (PG RVPA). rTOF patients with PG RVPA < 15 mmHg and �15 mmHg were classified as low pulmonary stenosis (rTOF low , n = 19) and high pulmonary stenosis (rTOF high , n = 13) subgroups, respectively. Magnetic resonance imaging tissue phase mapping was employed to evaluate the voxelwise biventricular myocardial motion in longitudinal (Vz), radial (Vr), and circumferential (Vφ) directions. Results The rTOF low subgroup presented higher pulmonary regurgitation fraction than rTOF high subgroup (p < 0.001). Compared with the normal group, only rTOF low subgroup presented a decreased RV ejection fraction (RVEF) (p < 0.05). The rTOF low subgroup showed decreased systolic and diastolic Vz in RV and LV, whereas rTOF high subgroup showed such change only in RV. In rTOF low subgroup, RVEF significantly correlated with RV systolic Vr (r = 0.56, p < 0.05), whereas LVEF correlated with LV systolic Vz (r = 0.51, p = 0.02).

Our results suggest asymptomatic adolescents with repaired TOF had abnormal biventricular myocardial performance, as demonstrated by combined 2D speckle-tracking and 3D echocardiography. The implications of these findings for management of adolescents late after repaired TOF remain to be determined.

Lung perfusion scintigraphy is a valuable, non-invasive screening tool in the assessment of branch pulmonary artery stenosis in children after TOF.