Diagnostic Value Of Color Ultrasound For Tetralogy Of Fallot

ObjectiveUse HDF and conventional color Doppler ultrasound respectively to observe the blood flow of ventricular septal defect, overriding aorta and pulmonary stenosis. And improve the understanding of small ventricular septal defect by compare their difference.Objects and MethodsCollect29600pregnant women from January2011to December2013, including outpatients and inpatients, who went to Liuyang maternal and children health care center, for ultrasonic inspection. There were180patients with ventricular septal defect, among which22patients were diagnosed with tetralogy of Fallot. Pregnancy26.3weeks±3.5days(23～35weeks). The inclusion criteria was that the fetus was suspected to have ventricular septal defect and overriding aorta.Examine each fetus routinely with ultrasonic diagnostic apparatus of Philips IU22and E8. Measure the biparietal diameter, cerebellum diameter, head circumference, abdominal circumference, femur length, humerus length, placenta, amniotic fluid and other basic parameter of each fetus. Estimate the weight of each fetus. Choose the mode of foetal heart, and use an eight-step method to exclude the common congenital heart malformations, like single atrium, single ventricle, transposition of the great arteries, persistent truncus arteriosus and so on. Place the sampling volume in the defect of ventricular septum, make the acoustic beam perpendicular to the ventricular septum, adjust the spectrum to the best condition, and save the best image and record the measurement of the defect of ventricular septum. Define2～4mm as small ventricular septal defect, and greater than or equal to4mm as large defect. On the basis of improving the detection rate of ventricular septal defect, screen the overriding aorta, monitoring the blood flow of left and right ventricle flowing into the aorta at the same time. Then check if there is pulmonary stenosis and right ventricular hypertrophy.Results1. In patients who were suspected to suffer from ventricular septal defect, when the defect was greater than or equal to4mm, the positive rate of HDF and conventional color Doppler ultrasound was pretty close and there was no significant statistical difference (P>0.05). When the defect was2～3.9mm, there was difference between the positive rate of HDF and conventional color Doppler ultrasound. HDF was more sensitive in displaying the blood flow. And the difference was statistically significant.2. In patients who were suspected to suffer from ventricular septal defect, when the defect was greater than or equal to4mm, and was complicated by overriding aorta, there was no significant statistical difference between HDF and conventional color Doppler ultrasound (P>0.05). When the defect was2～3.9mm, there was significant difference between HDF and conventional color Doppler ultrasound. 3. Compare the conventional apical four-chamber view and four views scanning (fou-chamber view+the view of the left and right ventricular outflow tract+three vessels and trachea view). Scan the fetal cardiac system with eight views and scan continuously and dynamically can increase the detection rate of tetralogy of Fallot obviously.Conclusion1. HDF is a noninvasive, economical and convenient technique. It can increase the detection rate when applied to the examination of fetal tetralogy of Fallot.2. Compare the conventional apical four-chamber view and four views scanning (fou-chamber view+the view of the left and right ventricular outflow tract+three vessels and trachea view). Scan the fetal cardiac system with eight views and scan continuously and dynamically can increase the detection rate of tetralogy of Fallot obviously.