Persistent subclinical myocardial dysfunction among infants with Fetal growth restriction at one year of age

Abstract Background Fetal growth restriction (FGR) is associated with altered cardiac development and subclinical myocardial dysfunction; however, longitudinal data during infancy are limited. This study evaluated serial changes in cardiac structure and function in infants with FGR during the first year of life. Methods This prospective longitudinal study included 128 FGR neonates and 64 appropriate-for-gestational-age (AGA) neonates, of whom 39 early-onset FGR (EOFGR), 47 late-onset FGR (LOFGR), and 64 AGA neonates completed the 1-year follow-up. FGR was diagnosed antenatally using estimated fetal weight <10th percentile with abnormal Doppler findings and confirmed postnatally using Intergrowth-21 standards. Cardiac evaluation included conventional echocardiography, tissue Doppler imaging, and speckle-tracking echocardiography. Results At birth, FGR infants showed significantly lower anthropometric parameters and smaller cardiac dimensions compared with AGA controls. By 12 months, both FGR groups demonstrated catch-up growth with normalization of left ventricular dimensions and wall thickness. However, speckle-tracking analysis revealed persistent subclinical myocardial dysfunction. Global longitudinal strain and strain rate indices remained significantly impaired across follow-up. Right ventricular dysfunction was evident at 12 months, particularly in the EOFGR group. Conclusion Despite structural normalization and catch-up growth, infants with FGR exhibit persistent subclinical myocardial dysfunction during the first year of life. Impact Infants with fetal growth restriction exhibit reduced cardiac size and altered myocardial function at birth compared to AGA neonates. Both early- and late-onset FGR infants demonstrate significant catch-up growth and cardiac structural normalization by 12 months. Despite normalization of cardiac dimensions, speckle-tracking parameters (GLS and strain rates) remain impaired throughout infancy. Right ventricular dysfunction becomes evident by 12 months, particularly in early-onset FGR infants. Early myocardial impairment in FGR infants may represent a precursor to future cardiovascular risk, highlighting the need for longitudinal cardiac surveillance.