Speckle tracking analysis to evaluate the size, shape, and function of the atrial chambers in fetuses with d-transposition of the great arteries to predict the need for neonatal urgent balloon atrial septostomy

Abstract

Introduction: Speckle tracking analysis was used to evaluate right (RA) and left (LA) atria size, shape and contractility to create a probability calculator to identify fetuses at risk for urgent neonatal balloon atrial septostomy (BAS).

Methods: The study group consisted of 39 fetuses with D-TGA, of which 55% (N = 22) required neonatal BAS and 45% (N = 17) did not. The RA and LA end-diastolic areas, lengths, widths, and sphericity indices as well as global, longitudinal, and transverse contractility were measured with speckle tracking analysis. The z-scores of the measurements were compared to 200 controls. Logistic regression analysis of the computed z-score measurements was performed to separate fetuses requiring urgent neonatal atrial BAS from those who did not.

Results: The following z-score values for all fetuses with D-TGA, irrespective of whether they required neonatal BAS, that were significantly less than controls: RA base sphericity index, basal-apical length fractional shortening, fractional area change, lateral wall annular plane systolic excursion (APSE), and longitudinal reservoir strain; LA mid-chamber width, fractional shortening, ejection fraction, basal-apical length fractional shortening, atrial ejection volume, septal wall APSE, and reservoir strain. The following z-score values were significantly larger than control values: RA/LA mid-chamber width, RA/LA base width, and RA mid-chamber length. Logistic regression analysis identified the following five measurements that correctly identified 19 of 22 fetuses requiring urgent neonatal atrial BAS with a sensitivity of 86.4%, a false-positive rate of 11.8% and a positive predictive value of 90.4%: (1) LA mid-chamber transverse fractional shortening, (2) RA mid-chamber end-diastolic width, (3) RA basal-apical length fractional shortening, (4) RA mid-chamber fractional shortening, and (5) RA fractional area change.

Conclusion: Using the measurements described in this study identified significant differences between all fetuses with D-TGA and controls, as well as identified measurements that predicted the probability of D-TGA fetuses requiring neonatal septostomy.

Keywords: D-transposition of the great arteries; balloon atrial septostomy; congenital heart defects; fetal echocardiography; prenatal diagnosis.