Evualuation Of Normal Fetal Right Ventricular Function In Second And Third Trimester By Using Full Volume Real-time Three-dimensional Echocardiography

Objective:To evaluate the normal fetal right ventricular function in second and third trimester by using full volume real-time three-dimensional echocardiography (RT-3DE)Study Populations and Methods:From May 2009 to October 2009, we randomly enrolled 115 consecutive pregnant women, of whom 109 were recruited into study group (age 27.6±3.8 years, range 17～40 years, gestation age 29.1±4.6 weeks, range 20～40weeks).Six were ruled out because of poor echocardiographic image quality.A detailed echocardiographic examination was performed with a Philips iE33 ultrasound system with 1.0～5.0 MHz sector transducer and full-volume matrix probe.1. General obstetrics examination:fetal position was assessed and fetal gestational age was estimated by measuring biparetal diameter and femur length. Left or right ventricle was distinguished by fetal position, spine, liver, aerogastria, descending aorta or the blood direction of foramen of ovale. 2. Three cardiac cycles of the fetal echocargiograms were captured in cine-loop format including:a four-chamber view on two-dimensional echocardiography, two right ventricular reverse planes (a four-chamber view and a two-chamber view), a four-chamber "Full volume"imaging on RT-3DE.2DE right ventricular volumes were measured by Shimanaki rule and biplane Simpson's method. Fetal RT-3DE right ventricular volumes were outlined and calculated by the analysis software of "Full volume" imaging of RT-3DE. The right ventricular end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV), ejection fraction (EF) and cardiac output (CO) measured by three different calculations were compareded3. Statistic analysisAll statistics were carried out using SPSS 13.0 software. A probability value<0.05 was considered as statistically significant.Results:One hundred and nine fetuses ranging from 20+2 to 40+1 gestational weeks were included, six fetuses with poor echocardiographic image quality were excluded.The fetuses diagnosed during the study period were examined with a cardiac anomaly and their ventricular volumes were compared with three different calculations.95% confidence in Shimanaki rule RVEDV ranged from a mean of 2.70ml to a mean of 3.54ml,RVESV ranged from a mean of 0.90ml to 1.23ml, SV ranged from a mean of 1.78ml to a mean of 2.33ml, CO ranged from a mean of 255.07ml to a mean of 331.42ml,EF ranged from a mean 42%of to a mean of 56%.In biplane Simpson's method RVEDV ranged from a mean of 1.47ml to a mean of 1.94ml,RVESV ranged from a mean of 0.49ml to 0.69ml, SV ranged from a mean of 0.96ml to a mean of 1.26ml, CO ranged from a mean of 138.13ml to a mean of 181.07ml,EF ranged from a mean 53%of to a mean of 68%.In RT-3DE RVEDV ranged from a mean of 1.39ml to a mean of 1.80ml,RVESV ranged from a mean of 0.46ml to 0.62ml, SV ranged from a mean of 0.91ml to a mean of 1.19ml, CO ranged from a mean of 131.06ml to a mean of 170.37ml,EF ranged from a mean 52%of to a mean of 68%.In Shimanaki rule every volume parameters were over estimated. Compared with biplane Simpson's method,the RT-3DE volume parameters were concentrative. The result showed that there were significant difference between Shimazaki rule and biplane Simpson's method (P<0.05).There were significant difference between Shimazaki rule and RT-3D (P<0.05), too, There was no difference between biplane Simpson's and RT-3DE(P>0.05).Three methods were positively correlated with gestational age, biplane Simpson method and RT-3DE much more significantly compared with Shimazaki rule.A paired t test directly compared intraobserver and interobserveron the three caculations.In Shimazaki rule and Simpson method it revealed no systematic difference (P>0.05),but in RT-3DE it revealed significant systematic difference(P<0.05).Conclusion:RT-3DE provides an accurate volume measuring method for irregular shaped RV for its independent of geometric assumption in calculating volumes. It may offer a useful approach for better understanding the characteristic of fetal myocardial properties during fetal heart development. Then they are useful to evaluate the changing of the fetal heart function along with the advancing gestational ages.;real-time three-dimensional echocardiograpy evaluation of the fetal heart right ventricular function is feasible and reproducible.