Assessment of global and regional strain left ventricular in patients with preserved ejection fraction after Fontan...

To evaluate the use of the tissue tracking (TT) technique to measure myocardial strain left ventricular in post-Fontan children with preserved ejection fraction (pEF). Nineteen (male/female, 10/9) patients with univentricular hearts after completion of the Fontan circulation (post-Fontan group) and 19 age- and gender-matched healthy children (control group) were retrospectively enrolled. Cardiovascular magnetic resonance (CMR) imaging was conducted on a 1.5-T MRI scanner. Global and regional strains of the left ventricle in post-Fontan patients (EF > 55%) and controls were obtained using CMR-TT software. The Mann-Whitney U test was used to compare parameters between the two groups. Correlation between EF and strain was investigated using Pearson correlation coefficients. The Bland-Altman method was used to identify the inter- and intra-observer agreement in measurement of global strain. Global longitudinal strain was lower in post-Fontan patients than in healthy controls (- 18.87 ± 4.61 vs. -19.72 ± 1.58; P = 0.54), though the difference was not statistically significant. Global circumferential strain and global radial strain were significantly lower in post-Fontan patients than in healthy controls (- 14.55 ± 3.79 vs. -19.91 ± 1.97; P < 0.001; and 29.62 ± 8.41 vs. 36.85 ± 5.95; P = 0.01; respectively). The regional circumferential strain (RCS) decrease was marked in regional segments compare with post-Fontan patients and controls (basal, - 11.81 ± 2.98 vs. - 16.21 ± 2.72, P < 0.001; mid, - 15.05 ± 3.31 vs. - 20.17 ± 2.28, P = 0.005; apical, - 16.86 ± 3.09 vs. - 23.37 ± 2.62, P < 0.001). All circumferential and longitudinal parameters had an inter-observer ICC of ≥ 0.85, but this coefficient was lower for radial parameters. CMR-TT appears to be a feasible technique for identification of early myocardial dysfunction in post-Fontan with pEF.