Classifying the Size of an Atrial Septal Defect According to Echocardiographic Parameters and its Association with the Clinical Presentation in Pediatrics

Background: Few studies are using linear echocardiographic measurements for classifying the size of Atrial Septal Defect (ASD).Objectives: Investigate the relationship between ASD hemodynamic repercussions and ASD diameter to the mitral annulus diameter (MI/ASD) ratio and ASD diameter to the interatrial septum diameter (ASD/septum) ratio, and describe cutoff points to classify the size of the defect.Methods: An observational, prospective, cross-sectional study, including subjects aged 1 month and 18 years diagnosed with isolated ASD.Hemodynamic repercussion was quantified by clinical evaluation, tricuspid annulus (TA) Z-score, subjective estimation of the enlargement of the right chambers, and the relationship between systemic and pulmonary flows (QP/QS) on echocardiography.Its association with ASD/septum and MI/ASD measurements was also studied.A value of p < 0.05 was considered statistically significant.Results: Thirty-five subjects, mean age 6.3 years, 69% female, mean ASD 13.5 mm.There was a correlation between MI/ASD and the clinical classification of ASD (Pearson: -0.61; p < 0.001), ASD/septum (Pearson: -0.80; p < 0.001), and QP/QS (-0.76; p < 0.001).There was a correlation between ASD/septum and the clinical classification of ASD (Pearson: 0.56; p < 0.001), QP/QS (0.63; p = 0.001), subjective assessment of the right chambers (0.62; p < 0.001), and a weak correlation with the TA Z-score (0.35; p = 0.04).According to the operating characteristic curve for the stable variable classification of ASD according to the subjective right chamber's size, an area of 0.85 was obtained for ASD/septum (p = 0.001).The cutoff point of 0.27 for large ASD showed sensitivity of 85%, specificity of 86.7%, positive predictive value (PPV) of 86%, negative predictive value (NPV) of 85.2%, and positive likelihood ratio of 6.39.Conclusions: ASD/septum was associated with the hemodynamic repercussion of ASD and was useful in detecting large ASD.