Abstract
Background：Shone’s syndrome is a rare complex with few data published on its prenatal diagnosis, this study aimed to compare the fetal echocardiographic features between Shone’s syndrome fetuses and coarctation of the aorta (CoA) fetuses to improve the prenatal diagnosis of Shone’s syndrome and identify the mitral valve obstruction associated with the anomaly. Methods: Retrospective study was performed. Between January 2015 to December 2019, fourteen fetuses diagnosed with Shone’s syndrome were enrolled and ten were analyzed in our final study, their clinical information and echocardiographic features were compared to normal controls (N=30) and CoA cases (N=10). The main points of identification were summarized. Results: Comparing to normal controls, the PA/AO ratio was increased in both Shone’s syndrome and CoA, but Shone’s syndrome fetuses had higher PA/AO ratio than CoA fetuses (P=0.006). RV/LV and TVC/MVC ratios were only elevated in Shone’s syndrome cases (P<0.0001, P<0.0001). Analysis revealed that the TVC/MVC ratio had the best capability in predicting Shone’s syndrome and fetuses with TVC/MVC ratio over 1.290 were more likely to have Shone’s syndrome rather than CoA. Meanwhile, the main points of identification in mitral valve obstruction included (1) restrictive opening of the mitral valve, thickened leaflets, echo-enhancement of chordae tendineae and single papillary muscle in short-axis section view; (2) decreased antegrade flow and abnormal flow pattern of mitral valve in color Doppler image. Chi-square test revealed that restrictive opening of the mitral valve and single papillary muscle were the most relevant features of mitral valve obstruction. Conclusions: There are several parameters of prenatal diagnosis of Shone’s syndrome by fetal echocardiography, including (1) echocardiographic measurements: elevated RV/LV ratio, PA/AO ratio and TVC/MVC ratio, of these, the TVC/MVC ratio has the best capability in predicting Shone’s syndrome; (2) morphologic changes in short-axis section view: restrictive opening of the mitral valve and single papillary muscle are the most relevant features of Shone’s syndrome.
Coarctation of the aorta: difficulties in prenatal diagnosis.
