Available online 11 April 2023

Remodelling and altered ventricular geometry have been described in premature-born adults. Although they seem to have an adverse cardiac phenotype, the impact of various degrees of prematurity on cardiac development has been scarcely reported. In this study, we evaluated the impact of gestational age (GA) at birth on cardiac dimensions and function at near term age among extremely preterm infants.

Retrospective single center cohort study of infants born <29 weeks GA between 2015-2019. Infants with available clinically acquired echocardiography between 34-43 weeks were included. Two groups were investigated: born <26 weeks or ≥26 weeks. All measurements were done by an expert masked to clinical data, using the raw images. The primary outcome was measurements of cardiac dimensions and function based on GA group. Secondary outcomes were the association between cardiac dimensions and post-natal steroid exposure, and with increments of GA at birth.

A total of 205 infants were included (<26 weeks n=102, ≥26 weeks n=103). At time of echocardiography, weight (2.4 ±0.5 vs 2.5 ±0.5 kg, p=0.86) and age (37.2 ±1.6 vs 37.1 ±1.9 weeks, p=0.74) were similar between groups. There was no difference in metrics of right-sided dimensions and function. However, left-sided dimensions were decreased in infants born <26 weeks, including systolic left ventricle (LV) diameter (1.06 ±0.20 cm vs 1.12 ±0.18 cm, p=0.02), diastolic LV length (2.85 ±0.37 vs 3.02 ±0.57 cm, p=0.02), and estimated LV end diastolic volume (EDV) (5.36 ±1.69 vs 6.01 ±1.79 mL, p=0.02).

In our cohort of very immature infants, birth at the extreme of prematurity was associated with smaller left cardiac dimensions around 36 weeks of corrected age. Future longitudinal prospective studies should evaluate further the impact of prematurity on LV development and performance, and their long-term clinical impact.

2023 Published by Elsevier Inc. on behalf of the American Society of Echocardiography.