Midtrimester Evaluation of Fetal Heart with Fetal Heart Quantification (FetalHQ) Related to Maternal Pathology

<b>Background</b>: Echocardiography currently represents the gold standard for the anatomical and functional assessment of the fetal heart by experienced operators. FetalHQ (VolusonTM) provides a semi-automated speckle-tracking analysis of the fetal heart with promising results for the reliable assessment of cardiac remodeling, specifically of size, shape, and contractility. <b>Methods</b>: We conducted a retrospective study comparing 108 controls, 119 obesity (BMI ≥ 30), 69 pre-pregnancy diabetes mellitus (DM), 41 gestational diabetes mellitus (GDM), and 37 early fetal growth restriction (FGR) cases (19+0-22+6 weeks). FetalHQ was utilized during midtrimester echocardiographic exams to evaluate fetal myocardial thickness and left ventricular mass. <b>Results</b>: Myocardial thickness was increased in DM (median 0.21 [IQR 0.17-0.23] cm) vs. controls (0.17 [0.15-0.21] cm; <i>p</i> < 0.01) and reduced in FGR (0.13 [0.11-0.18] cm; <i>p</i> < 0.01). Left ventricular mass increased in obesity (0.98 [0.62-1.19] g) and DM (1.12 [0.94-1.17] g) vs. controls (0.73 [0.56-0.97] g; both <i>p</i> < 0.01). <b>Conclusions</b>: Fetal cardiac remodeling, especially myocardial thickness and left ventricular mass adaptations, is detectable in fetuses from high-risk pregnancies starting from the second trimester. Advanced speckle-tracking techniques, such as fetalHQ, provide valuable early risk stratification and may support the need for systematic fetal cardiac screening and monitoring during gestation in selected groups of patients.