225 - Association of Gestational Age at Birth with Left Cardiac Dimensions at Near Term Corrected Age Among Extremely Preterm Infants

Poster Number: 225
Publication Number: 226.33

Shiran Sara Moore, Tel Aviv Sourasky Medical Center & McGill University, Ramat Hasharon, Tel Aviv, Israel; Gabriela De Carvalho Nunes, Dalhousie University Faculty of Medicine, Saint John, NB, Canada; Daniela Villegas Martinez, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Adrian Dancea, MUHC, Westmount, PQ, Canada; Punnanee Wutthigate, Mahidol University, Bangkok, Krung Thep, Thailand; Jessica Simoneau, McGill University Faculty of Medicine and Health Sciences, Vercheres, PQ, Canada; Marc Beltempo, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Guilherme Sant'Anna, McGill University Health Center, MONTREAL, PQ, Canada; Gabriel Altit, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada

Background: Remodeling 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. 

Objective: 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.

Design/Methods: A 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: those 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.

Results: A total of 205 infants were included (< 26 weeks n=102, ≥26 weeks n=103) (Table 1). 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 < 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) (Table 2). In a multilinear regression analysis LV-EDV was found to be significantly associated to GA at birth, but not exposure to post-natal steroids. There was an increasing trend in LV-EDV with increasing GA (Figure 1).

Conclusion(s): 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. These findings could portray a signal towards better understanding the pathophysiology of cardiac development in prematurity.