Divergent Right Ventricular Adaptation in Fetal Growth Restriction Subtypes Revealed by Quantitative Cardiac Profiling

OBJECTIVE: This investigation delineates ventricular adaptive patterns across clinical subtypes of fetal growth restriction (FGR) using fetal heart quantification (fetal HQ) technology. METHODS: Between June 2021 and June 2022, 30 singleton FGR pregnancies (16 early-onset, 14 late-onset) and 60 normal controls were enrolled, according to the inclusion and exclusion criteria. Data collected included maternal-fetal parameters, fetal biometry, and Doppler indices. Standard dynamic four-chamber views were analyzed offline using fetal HQ. RESULTS: Both FGR groups delivered earlier and had lower birth weights than controls (both p ˂ 0.05). Myocardial performance index was elevated in FGR fetuses. Left ventricle (LV) global longitudinal strain (GLS) and fractional area change (FAC) were reduced in both early- and late-onset FGR compared to controls (GLS: -22% ± 5% vs. -27% ± 4%, p = 0.001; -23% ± 5% vs. -27%±4%, p = 0.020; FAC: 0.43 ± 0.06 vs. 0.50 ± 0.06, p = 0.002; 0.44 ± 0.08 vs. 0.50 ± 0.06, p = 0.022). Right ventricle (RV) FAC was also lower in both FGR groups (0.36 ± 0.09 vs. 0.42 ± 0.06, p = 0.028; 0.33 ± 0.13 vs. 0.42 ± 0.06, p = 0.001). Fractional shortening (FS) was impaired in RV selected segments in early-onset FGR and across most segments in late-onset FGR (both p ˂ 0.05). CONCLUSION: GLS and FS detect subclinical ventricular dysfunction in FGR, with alterations in either parameter paralleling subsequent FAC modifications. The two clinical subtypes demonstrate distinct right ventricular adaptive patterns.