We have developed a novel, high resolution, image acquisition, and quantification approach to study a whole in-vitro heart at myofibre resolution, providing integrated 3D structural information at microscopic level without any need of tissue slicing and processing. This superior imaging approach opens up new possibilities for a systems approach towards analysing cardiac structure and function, providing rapid acquisition of quantitative microstructure of the heart in a near native state.

Fetal growth restriction (FGR) because of placental insufficiency affects 5% to 7% of pregnancies and represents one of the leading causes of perinatal morbidity and mortality.1 Numerous historical cohort studies 2 and animal models 3 have demonstrated that FGR has a strong association not only with metabolic but also with primary cardiovascular remodeling that lead to long-term adverse consequences in later life. The rapid cell proliferation and differentiation during fetal growth are sensitive to any of the even smallest changes damaging the environment that can lead to permanent alterations in structural and functional constitution, which may persist into the adult life. 2 The heart is a central organ in the prenatal adaptation to placental insufficiency and fetal hypoxia. Previous studies have demonstrated remodeled hearts (more globular) with signs of systolic and diastolic dysfunction and preserved ejection fraction. [4][5][6] FGR cases are associated with prenatal adverse cardiac remodeling 4,5 that persists postnatally, 6 and low birth weight was linked to increased cardiovascular mortality in adulthood.2 Chronic pressure/volume overload together with hypoxia in utero have been postulated as the potential underlying mechanistic pathway of prenatal cardiovascular remodeling in FGR. 5,6 Editorial see p 759 Clinical Perspective on p 787Although evaluation of cardiac function with echocardiography has traditionally been limited to volume-based assessment, recent developments in cardiac ultrasound allow the noninvasive measurement of cardiac deformation with direct assessment of myocardial muscle by assessing regional Background-Fetal growth restriction (FGR) is associated with global adverse cardiac remodeling in utero and increased cardiovascular mortality in adulthood. Prenatal myocardial deformation has not been evaluated in FGR to date. We aimed to evaluate prenatal cardiac remodeling comprehensively in FGR including myocardial deformation imaging. Methods and Results-Echocardiography was performed in 37 consecutive FGR (defined as birthweight <10th centile) and 37 normally grown fetuses. A comprehensive fetal echocardiography was performed including tissue Doppler and 2-dimensional-derived strain and strain rate. Postnatal blood pressure measurement at 6 months of age was also performed. FGR cases showed signs of more globular hearts with decreased longitudinal motion (left systolic annular peak velocity: controls mean 6 cm/s [SD myocardial strain and strain rate. [7][8][9] Strain is defined as change in length/thickness of a segment of myocardium relative to its resting length and is expressed as a percentage; strain rate is the velocity of this deformation.7-9 Myocardial deformation imaging has demonstrated a high sensitivity for detecting preclinical myocardial dysfunction in various pathological conditions characterized by myocardial dysfunction, despite preserved ejection fraction, such as asymptomatic carriers of hypertrophic cardiomyopathy, sarcomeric mutations, Fabry disease, or myocardial ste...