Application Value Of Quantification Of Distances And Angles Between Aortic Arch And Ductal Arch In The Diagnosis Of Fetal Right Aortic Arch

Objective:To evaluate the application value of quantification of distances and angles between aortic arch and ductal arch in the diagnosis of fetal right aortic arch(RAA).Methods:Fifty-two fetuses with isolated RAA were selected as study group(RAA.Group)and randomly paired with one hundred and twenty-one normal cases as control group.The diameters of the ductus arteriosus and the aortic arch,the distance and the angle(AP angle)between the two arches were measured on the three vessel views(3 VT view),calculate the ratio of the diameter between the ductus arteriosus and the aortic arch.Statistical analysis was performed for the measurements of each parameter between the two groups.Results:Compared with the control group,the values of the distance between the ductus arteriosus and the aortic arch increased[4.86(4.16-5.74)mm vs 1.59(1.38-1.76)mm],and the AP angle decreased[(12.96±1.83)° vs(22.14±1.35)°]in RAA group(Z=-10.416、P<0.05,t=32.481、P<0.05).There was no significant difference between the two groups in the values and ratios of the diameters between the ductus arteriosus and the aortic arch,diameters of the aorta and pulmonary artery,velocities of aortic valve and pulmonary valve(P>0.05).In both groups,there were no correlations with the gestational age in the AP angle and the ratio of the diameter between the ductus arteriosus and the aortic arch(AP angle:r=0.148、P=0.294;r=0.060、P=0.514;ratio of the diameter between the ductus arteriosus and the aortic arch:r=0.029、P=0.818,r=0.108、P=0.1 80),while the distance between the ductus arteriosus and the aortic arch,diameters of-the ductus arteriosus and the aortic arch,diameters of the aorta and pulmonary artery,velocities of aortic valve and pulmonary valve were all linearly positively correlated with the gestational age,in which the diameters of-the ductus arteriosus and the aortic arch,diameters of the aorta and pulmonary artery were closely correlated(diameters of the ductus arteriosus:r=0.731、P=0.000,r=0.592、P=0·000;diameters of the aortic arch:r=0.668,P=0.000,r=0.592、p=0.000;diameters of the aorta r=0.798、P=0.000,r=0.840、P=0.000;diameters of the pulmonary artery:r=0.776、P=0.000,r=0.817,P=0.000)Conclusion:Measurements of the distances and angles between aortic arch and ductal arch in the 3VT view of fetal echocardiography were simple and feasible.which may have supplementary role in the diagnosis of the fetal RAA with left-sided ductus arteriosus.