BackgroundRight ventricular dilation and dysfunction is a common long‐term complication in patients with repaired pulmonary stenosis (rPS). Additionally, abnormal right and left ventricular interactions have been reported in right‐sided heart defect after intervention, including in pulmonary stenosis.PurposeTo analyze ventricular strain, remodeling, and left and right ventricular interactions in rPS patients with preserved right ventricular ejection fraction (RVEF) compared with healthy children using cardiac magnetic resonance.Study TypeA cross‐sectional study.PopulationIn all, 34 rPS patients and 10 healthy children volunteers (controls).Field Strength/Sequence3.0T/2D balanced steady‐state free precession (2D b‐SSFP) cine, late gadolinium enhancement (LGE), and 2D phase contrast (2D‐PC).AssessmentPulmonary regurgitation (PR) fractions of the main pulmonary artery, biventricular volumes, masses, function, and cardiac strain.Statistical TestsMann–Whitney U‐test, t‐test, Pearson correlation coefficients, Spearman's correlation coefficients, and intraclass correlation coefficients analysis were performed.ResultsFor group analysis, the right ventricular (RV) global circumferential strain and radial strain were significantly increased in patients when compared with controls (−13.57 ± 2.69 vs. −5.91 ± 3.16, P < 0.001; 25.31 ± 8.12 vs. 9.87 ± 5.32, P < 0.001, respectively). The fraction of PR displayed moderate correlation with right ventricular end‐diastolic volume index (RVEDVi) (r = 0.452, P = 0.022). RVEDVi and mass index were larger in patients vs. control (104.92 ± 27.46 vs. 85.15 ± 11.98, P = 0.016; 18.28 ± 4.95g/m2 vs. 11.67 ± 2.14 g/m2, P < 0.001, respectively). Patients presented with preserved left ventricular ejection function, but was lower than healthy controls (60.89% ± 4.89% vs. 65.95% ± 4.56%, P = 0.006). Regional circumferential strain of segment 3 of left ventricle (LV) were significantly decreased in patients (−7.79 ± 6.52 vs. −13.56 ± 3.22, P = 0.003).Data ConclusionCompensated increased RV strain, myocardial remodeling of RV, and adverse right and left ventricular interactions occur in rPS patients with preserved RVEF. The decreased interventricular septum strain may lead to impaired LV function due to RV dilation as a result of PR.Level of Evidence: 3Technical Efficacy Stage: 3J. Magn. Reson. Imaging 2020;52:129–138.