Fetal Left Ventricle Function Evaluated by Two-Dimensional Speckle-Tracking Echocardiography across Clinical Stages of Severity in Growth-Restricted Fetuses.

Fetal growth restriction (FGR) can result in adverse perinatal outcomes due to cardiac dysfunction. This study used 2D speckle-tracking echocardiography to assess left ventricle (LV) longitudinal strain across FGR severity stages. A prospective longitudinal cohort study measured global (GLS) and segmental LV longitudinal strain in FGR fetuses, with evaluations conducted at various time points. FGR was classified into subtypes based on published criteria using fetal weight centile and Doppler parameters. A linear mixed model was employed to analyze repeated measures and compare Z-score measurements between groups throughout gestational age. The study included 40 FGR fetuses and a total of 107 evaluations were performed: 21 from small for gestational age (SGA), 74 from the FGR stage I, and 12 from the FGR stage ≥ II. The results indicate that SGA and stage I FGR fetuses exhibit higher LV GLS than stages ≥ II. Throughout gestation, SGA and FGR stage I fetuses showed similar behavior with consistently better LV GLS values when compared to FGR stages ≥ II. No significant differences were observed in LV GLS strain behavior between SGA and FGR stage I. In conclusion, all FGRs show signs of early cardiac dysfunction, with severe cases demonstrating significantly a lower LV GLS when compared to mild cases, suggesting deterioration of cardiac dysfunction with progression of fetal compromise.

Longitudinal Behavior of Left-Ventricular Strain in Fetal Growth Restriction.

Fetal growth restriction (FGR) is associated with an increased risk of adverse outcomes resulting from adaptive cardiovascular changes in conditions of placental insufficiency, leading to cardiac deformation and dysfunction, which can be evaluated with 2D speckle tracking echocardiography (2D-STE). The aim of the present study was to evaluate whether reduced fetal growth is associated with cardiac left-ventricle (LV) dysfunction, using 2D-STE software widely used in postnatal echocardiography. A prospective longitudinal cohort study was performed, and global (GLO) and segmental LV longitudinal strain was measured offline and compared between FGR and appropriate-for-gestational-age (AGA) fetuses throughout gestation. All cases of FGR fetuses were paired 1:2 to AGA fetuses, and linear mixed model analysis was performed to compare behavior differences between groups throughout pregnancy. Our study shows LV fetal longitudinal strain in FGR and AGA fetuses differed upon diagnosis and behaved differently throughout gestation. FGR fetuses had lower LV strain values, both global and segmental, in comparison to AGA, suggesting subclinical cardiac dysfunction. Our study provides more data regarding fetal cardiac function in cases of placental dysfunction, as well as highlights the potential use of 2D-STE in the follow-up of cardiac function in these fetuses.

Gestational Age-Adjusted Reference Ranges for Fetal Left Ventricle Longitudinal Strain by Automated Cardiac Motion Quantification between 24 and 37 Weeks' Gestation.

INTRODUCTION: The objective of this study was to construct gestational age (GA) based reference values for left ventricle (LV) longitudinal strain in normal fetuses, between 24 and 37 weeks' gestation, assessing its feasibility and reproducibility with automated cardiac motion quantification software (aCMQ-QLab), which is widely used in postnatal echocardiography. METHODS: This prospective study included healthy gravid women with singleton pregnancies and no evidence of fetal structural cardiovascular disease. Fetal echocardiographies were performed between 24 and 37 GA. 2D four-chamber view clips were recorded and LV longitudinal strain was analyzed offline. Intra- and interobserver reproducibility between 2 independent observers was evaluated by intraclass correlation coefficients (ICC) and Bland-Altman scatterplots. Regression analysis was used to determine GA adjusted reference ranges and construct nomograms. RESULTS: LV longitudinal strain measurements were feasible in 95.4% of acquisitions. 435 clips were obtained. Intra- and interobserver ICC were 0.998 (95% CI 0.997-0.999) and 0.991 (95% CI 0.984-0.995), respectively. The global longitudinal strain and the middle and apical LV segments showed progressive decline as GA advanced, whereas the basal segments remained stable. CONCLUSIONS: Assessment of LV longitudinal strain by aCMQ-QLab is feasible, reproducible, and within normal ranges. Our results offer more information regarding fetal cardiac function assessment with 2D speckle tracking techniques, aiding in the introduction of this software into research practice, encouraging the realization of more studies, and probably helping in its future use in clinical practice, allowing longitudinal surveillance of strain without intervendor variability and aiding in follow-up of fetal cardiac conditions before and after birth, as it is the most commonly used software postnatally.