Normal Fetal Cardiovascular Parameters Obtained By Color Doppler Echocardiography

ObjectiveCongenital heart disease is the most common congenital malformation. In China nowadays, there are more than 100,000 newborns delivered with congenital heart disease every year. Fetal echocardiography could already estimate the heart structure and the blood dynamics change well, as well as the early diagnosis of the fetal congenital cardiovascular malformation and all kinds of arrhythmi-a. The echocardiography has been widely used in those western developed countries. In our country, it has more and more commonly been applied clinically in many hospitals and Maternal and Children's Health Care Hospitals. However, the fetal Echocardiography (ECG) needs more techniques than that of adult and infant, because of the immaturity in the following aspects, such as the screening skill, routine section examination, diagnosis standard and differentiation diagnosis et al. In our study, we measured the normal fetal cardiovascular dimension and blood flow velocity in 14 - 42 gestational weeks with the transabdominal ECG. By establishing the normal value and lineal regression equation, we can further understand the developing characteristics of normal fetal heart in every gestational age, and in addition, provide the basis for the prenatal screening of the fetal cardiovascular malformation.MethodsA total of 309 pregnancies with the gestational age from 14 to 42 week, being normal during every routine prenatal examination and with the fetus developing accordance with their gestational age, were examined their fetal heart bythe ACCUVIX XQ ultrasound systems (fetal heart software). The systems were inter -faced with 2. 5 -3. 5MHz transducers and the measurement recorded on more 3 heart move cycle for play back and analysis. For those fetal heart suggested to be normal and the section clear, were further measured Left Atria ( LA) Right Atria (RA) Left Ventricle (LV) Right Ventricle (RV) Ascending Aorta (AAo) Main Pulmonary Artery ( MPA ) Coronary Sinus (CS) Superior Vena Ca-va(SVC) Inferior Vena Cava(IVC) Foramen Ovum (FO) by transabdominal ECG. Blood flow velocity peak value trans Aortic Valve (AV) Pulmonary Valve (PV) Tricuspid Valve (TV) E peak Mitral Valve (MV) E peak was detected by the impulse Doppler techniques. The data was recorded in the EXCEL of computer. The cardiovascular parameters changes with their gestational ages were determined by the relativity analysis and the lineal regression. According to the gestational periods, we calculated the normal value and the 95% confidence intervals of above parameters in this period. The changes of the ratio of LA and RA, LV and RV with the gestational week can be determined by the scatter plots analysis. All above statistics analysis was performed by SPSS12. 0.Results1. The value of fetal cardiovascular measured increased linearly correspondingly with the gestational age (P <0. 01) , right heart occupied the dominant position ( P < 0.01).2. RA/LA and RV/LV in the normal fetal heart did not develop correspondingly with the gestational age ( P > 0. 05) , which was more stable than those of the measurement of LA RA LV RA. So the detection of RA/LA and RV/LV was more valuable in our clinical work.3. The peak blood flow velocity at all of the valves increased correspondingly with the gestational age (P <0. 01). Right heart system occupied the dominant position, too.4. The inner diameter of coronary sinus could be measured in the 20th week of gestation, while the chamber diameters, aortic and pulmonary artery diameters could be detected clearly in the 14th week of gestation.Conclusions1. LA RA IVS LV RV FO CS SVC IVC AAo MPA MV E peak TV E peak AV PV of normal fetal heart linearly increase with the gestation ages. RA/LA and RV/LV are more stable and more with clinical value than LA RA LV RV themselves.2. The cardiac vascular diameter can be measured in the 14 th week of gestation by transabdominal ECG, which makes the earlier diagnosis of fetal cardiovascular malformation possible.3. The fetal right heart occupies the dominant position in not only the anatomy structure, but also the functions.