Alterations in myocardial strain can identify cardiac dysfunction and can be measured in the mid-gestation fetus. This study evaluates feasibility of strain measurements in early fetuses and establishes normal early fetal strain values.Methods
Normal fetal echocardiograms were reviewed for image adequacy for strain measurements in 12- to 14-week gestation fetuses. Two readers performed independent strain measurements. Values were compared with data from 40 normal second trimester fetuses.Results
Strain evaluation could be attempted in 36 of 53 (68%) of first trimester echocardiograms (mean gestation 13.4 weeks); excessive motion or inadequate imaging planes precluded tracking analysis in the remainder. Strain measurements were feasible in 19 of 53 fetuses (36%, or 53% of those in whom tracking was attempted). Peak systolic global longitudinal left ventricular (RV) and right ventricular (LV) strain were similar (LV = −13.9 ± 5.7%, RV = −14.4 ± 5.5%, p = 0.7). RV strain was higher in first trimester fetuses compared with second trimester normals (p = 0.003). Intraobserver and interobserver agreement were moderate to strong for peak global LV and RV strain but poor for regional basal and mid-septal segments.Conclusions
Strain measurements were feasible in one-third of retrospectively assessed early fetal echocardiograms. Global longitudinal strain may be higher in earlier than mid-gestation fetuses. © 2016 John Wiley & Sons, Ltd.