Purpose The accuracy of 2D and 3D strain analyses was evaluated by comparing strain and cardiac function parameters in Fontan repair patients and normal child volunteers. Methods We retrospectively enrolled 32 patients with Fontan circulation and 32 child volunteers who had undergone clinical cardiac magnetic resonance (CMR) assessment of the dominant ventricle with a 1.5-Tesla MRI scanner. Global and regional strain (2D and 3D) of the dominant ventricle in both groups was assessed using CMR feature-tracking. Correlations between cardiac function and strain data were assessed using Pearson’s correlation coefficient values. The intraclass correlation coefficient (ICC) and coefficient of variation (CoV) were determined to evaluate repeatability and agreement. Results: The 2D GLS showed significant differences between the Fontan repair patients and volunteers (-16.49 ± 5.00 vs. -19.49 ± 2.03; p = 0.002). The 2D GRS and 2D GCS showed no significant differences between two groups. 2D GRS: 38.96 ± 14.48 vs. 37.46 ± 7.77; 2D GCS: -17.64 ± 5.00 vs. -16.89 ± 2.96, respectively; p > 0.05). The 3D global radial strain (GRS), global circumferential strain (GCS), and global longitudinal strain (GLS) showed significant differences between the Fontan repair patients and volunteers (3D GRS: 36.35 ± 16.72 vs. 44.96 ± 9.98; 3D GLS: -8.86 ± 6.84 vs. -13.67 ± 2.44; 3D GCS: -13.70 ± 7.84 vs. -18.01 ± 1.78; p < 0.05, respectively). The ejection fraction (EF) and 3D GCS were significantly associated (r = -0.491, p = 0.004). The 3D GCS showed correlations with the indexed end-diastolic volume (EDV) (r = 0.523, p = 0.002) and indexed end-systolic volume (ESV) (r = 0.602, p < 0.001). 3D strain showed good reproducibility, with GCS showing the best inter-observer agreement (ICC=0.87 and CoV=5.15), followed by GLS (ICC=0.84 and CoV=5.36). Conclusion:3D GCS is feasible, highly reproducible, and strongly correlated with conventional cardiac function measures. 3D GCS assessments may be useful for monitoring abnormal myocardial motion in patients with Fontan circulation. Keywords Strain; Feature tracking; Fontan operation; Pediatric

Purpose The accuracy of 2D and 3D strain analyses was evaluated by comparing strain and cardiac function parameters in Fontan repair patients and normal child volunteers. Methods We retrospectively enrolled 32 patients with Fontan circulation and 32 child volunteers who had undergone clinical cardiac magnetic resonance (CMR) assessment of the dominant ventricle with a 1.5-Tesla MRI scanner. Global and regional strain (2D and 3D) of the dominant ventricle in both groups was assessed using CMR feature-tracking. Correlations between cardiac function and strain data were assessed using Pearson’s correlation coefficient values. The intraclass correlation coefficient (ICC) and coefficient of variation (CoV) were determined to evaluate repeatability and agreement. Results: The 2D GLS showed significant differences between the Fontan repair patients and volunteers (-16.49 ± 5.00 vs. -19.49 ± 2.03; p = 0.002). The 2D GRS and 2D GCS showed no significant differences between two groups. 2D GRS: 38.96 ± 14.48 vs. 37.46 ± 7.77; 2D GCS: -17.64 ± 5.00 vs. -16.89 ± 2.96, respectively; p > 0.05). The 3D global radial strain (GRS), global circumferential strain (GCS), and global longitudinal strain (GLS) showed significant differences between the Fontan repair patients and volunteers (3D GRS: 36.35 ± 16.72 vs. 44.96 ± 9.98; 3D GLS: -8.86 ± 6.84 vs. -13.67 ± 2.44; 3D GCS: -13.70 ± 7.84 vs. -18.01 ± 1.78; p < 0.05, respectively). The ejection fraction (EF) and 3D GCS were significantly associated (r = -0.491, p = 0.004). The 3D GCS showed correlations with the indexed end-diastolic volume (EDV) (r = 0.523, p = 0.002) and indexed end-systolic volume (ESV) (r = 0.602, p < 0.001). 3D strain showed good reproducibility, with GCS showing the best inter-observer agreement (ICC=0.87 and CoV=5.15), followed by GLS (ICC=0.84 and CoV=5.36). Conclusion:3D GCS is feasible, highly reproducible, and strongly correlated with conventional cardiac function measures. 3D GCS assessments may be useful for monitoring abnormal myocardial motion in patients with Fontan circulation. Keywords Strain; Feature tracking; Fontan operation; Pediatric

Purpose The accuracy of 2D and 3D strain analyses was evaluated by comparing strain and cardiac function parameters in Fontan repair patients and normal child volunteers. Methods We retrospectively enrolled 32 patients with Fontan circulation and 32 child volunteers who had undergone clinical cardiac magnetic resonance (CMR) assessment of the dominant ventricle with a 1.5-Tesla MRI scanner. Global and regional strain (2D and 3D) of the dominant ventricle in both groups was assessed using CMR feature-tracking. Correlations between cardiac function and strain data were assessed using Pearson’s correlation coefficient values. The intraclass correlation coefficient (ICC) was determined to evaluate repeatability and agreement. Results: The 3D global radial strain (GRS), global circumferential strain (GCS), and global longitudinal strain (GLS) showed significant differences between the Fontan repair patients and volunteers (3D GRS: 36.35 ± 16.72 vs. 44.96 ± 9.98; 3D GLS: -8.86 ± 6.84 vs. -13.67 ± 2.44; 3D GCS: -13.70 ± 7.84 vs. -18.01 ± 1.78; p < 0.05, respectively). The ejection fraction (EF) and 3D GCS were significantly associated (r = -0.491, p = 0.004). The 3D GCS showed correlations with the indexed end-diastolic volume (EDV) (r = 0.523, p = 0.002) and indexed end-systolic volume (ESV) (r = 0.602, p < 0.001). 3D strain showed good reproducibility, with GCS showing the best inter-observer agreement (ICC, 0.87), followed by GLS (ICC, 0.84) and GRS (ICC, 0.80). Conclusion:3D GCS is feasible, highly reproducible, and strongly correlated with conventional cardiac function measures. 3D GCS assessments may be useful for monitoring abnormal myocardial motion in patients with Fontan circulation. Keywords Strain; Feature tracking; Fontan operation; Pediatric