Objective：To improve the prenatal diagnosis of Shone’s syndrome and identify the mitral valve obstruction associated with the anomaly by comparing the fetal echocardiographic features between Shone’s syndrome and coarctation of the aorta (CoA).
Method: Between January 2015 to December 2019, 17 fetuses were diagnosed with Shone’s syndrome prenatally and 8 were analyzed in our final study, their data were compared to normal controls and CoA cases. The main points of identification were summarized.
Results: By comparing data between three groups, elevated PA/AO ratio and RV/LV ratio were detected in both Shone’s syndrome and CoA cases. However, TVC/MVC ratios was only increased in Shone’s syndrome. Analysis revealed that the TVC/MVC ratio had the best capability in predicting Shone’s syndrome. Ultrasonographic features of mitral valve obstruction in Shone’s syndrome were unique which help clinicians to distinguish the anomaly from CoA, including (1) morphologic changes in short-axis view: restrictive opening of the mitral valve with diastolic deformity, thickened leaflets, echo-enhancement of chordae tendineae and mitral valve, single papillary muscle or dominant papillary muscle; (5) in color Doppler image: decreased antegrade flow and abnormal flow pattern of mitral valve.
Conclusion: There are two key points of prenatal diagnosis of Shone’s syndrome which could help fetal cardiologist to distinguish Shone’s syndrome from CoA in clinical practice, including (1) echocardiographic measurements: the elevated TVC/MVC ratio; (2) morphologic changes of mitral valve indicating left ventricle inflow obstruction in two-dimension short-axis section view.