Normal Echocardiography Values of Aortic Arch Measurements in Neonates

Background: Accurate evaluation of aortic arch dimensions in neonates is crucial for early identification of congenital cardiac anomalies such as aortic coarctation. Although echocardiography is widely used, region-specific normative data integrating anthropometric and anatomical variations remain limited. This study aimed to establish reference echocardiographic measurements of the neonatal aortic arch and examine their relationship with body size and arch branching patterns. Methods: A cross-sectional, retrospective study was conducted at Prince Sultan Cardiac Center between January and December 2023. The cohort consists of 99 neonates, having echocardiograms within the first week of life for different clinical indications and revealing no congenital heart disease. Standard echocardiographic measurements were obtained for the aortic annulus, sinus of Valsalva, sinotubular junction, ascending aorta, proximal and distal transverse arches, and isthmus. Data were analyzed using SPSS version 28. Pearson’s correlation assessed associations between aortic dimensions and neonatal characteristics; linear regression identified predictors; one-way and two-way ANOVA evaluated differences across weight categories and arch types. Results: The mean gestational age was 37.99 ± 1.54 weeks, and the mean weight was 3.01 ± 0.60 kg. Echocardiographic assessment showed that the mean aortic annular diameter was 6.39 mm (SD = 0.69), the sinus of Valsalva measured 7.77 mm (SD = 0.88), and the sinotubular junction was 6.98 mm (SD = 0.75). The mean ascending aorta dimension was 7.88 mm (SD = 0.87), while the proximal transverse arch and distal transverse arch measured 6.73 mm (SD = 1.63) and 5.32 mm (SD = 0.85), respectively. The study showed that larger body weight was associated with greater proximal aortic dimensions. Two-way ANOVA revealed additional effects of arch type, where neonates with a common brachiocephalic trunk had larger ascending aortic dimensions than those with normal branching. Conclusion: This study establishes normative echocardiographic data for neonatal aortic arch dimensions and demonstrates that body weight and arch branching pattern significantly influence proximal aortic size. These findings enhance the precision of neonatal cardiac assessment and support early detection of structural variations and potential aortic abnormalities.