Ductus venosus blood velocity and the umbilical circulation in the seriously growth-retarded fetus.

Based on the assumption that the ductus venosus is regulator of oxygenated blood in the fetus, the present study investigated the blood flow velocity of the ductus venosus in relation to the umbilical circulation in the that seriously growth-retarded fetus. The study group of 38 fetuses (gestational week 17-39) had no chromosomal aberrations or structural malformations and had an ultrasonographic biometry of < 2.5th centile and birth weight of 相似文献   

Venous Doppler velocimetry in the surveillance of severely compromised fetuses.

OBJECTIVE: To investigate whether venous Doppler velocimetric signs of cardiac decompensation might predict fetal demise in severely compromised fetuses. MATERIAL AND METHODS: This was a prospective study involving 154 growth-restricted fetuses, 37 of which were found to have reversed flow in the umbilical artery (BFC III). Doppler velocimetry of the right hepatic vein and ductus venosus were investigated serially and the presence of umbilical venous pulsations also registered. Only the final examination prior to birth or fetal demise was accepted for analysis and related to obstetric outcome defined as gestational age at birth, birth weight and perinatal mortality. In cases of BFC III the venous velocimetry of 15 nonsurviving fetuses was compared to that of the 22 survivors. RESULTS: There was a significant correlation between venous blood velocity and placental vascular resistance. In the right hepatic vein there was a significant decrease in peak systolic and end-systolic velocities and an increase of maximum velocity during atrial contraction and pulsatility (P < 0.05). A decrease of all velocities and increase of pulsatility were noted in the ductus venosus (P < 0.05). A reversed flow in the ductus venosus was found in 9/37 fetuses and double umbilical venous pulsations in 16/37 fetuses. However, the hepatic vein seemed to be a better predictor of impending mortality than the ductus venosus. Changes in diastolic venous blood velocity and a double pulsation in the umbilical vein were closely related to perinatal mortality, although these parameters did not provide a useful threshold to optimize the timing of delivery. CONCLUSION: Diastolic venous velocimetry changes significantly in severely compromised fetuses. These changes might be of great clinical value in deciding on the timing of delivery to minimize damage to the fetus and newborn.     

Ductus venosus index: a method for evaluating right ventricular preload in the second-trimester fetus.

This study was designed to examine ventricular preload by measuring the ductus venosus index during the second trimester of pregnancy. A total of 137 women were entered into the study. Each fetus was examined with real-time, color and pulsed Doppler ultrasound. The color Doppler maximal velocity setting was adjusted so that the umbilical vein was homogeneous in color, did not demonstrate aliasing, and filled the venous lumen. The pulsed Doppler gate was placed within the ductus venosus in all subjects. Color Doppler identified a turbulent flow velocity within the ductus venosus which was not present in the umbilical vein, hepatic vein or inferior vena cava. The ductus venosus pulsed Doppler waveform demonstrated flow velocity from the umbilical vein to the heart during ventricular systole, the rapid filling phase of ventricular diastole, and atrial systole. However, flow velocity was decreased during atrial systole compared to ventricular systole and the rapid filling phase of diastole. The ductus venosus index was computed from the Doppler waveform of the ductus venosus at points consistent with ventricular and atrial systole ((ventricular systole - atrial systole)/ventricular systole). Regression analysis demonstrated a significant (p = 0.001) relationship between the ductus venosus index and gestational age (ductus venosus index = 75.5757 - 7.25484 x weeks gestation), standard error of the estimate = 7.21959; R = -0.451. One fetus with a hypoplastic left atrium and ventricle demonstrated a normal ductus venosus index. Two fetuses, one with pulmonary atresia and the second with severe cardiovascular dysfunction, demonstrated an abnormal ductus venosus index associated with absent flow velocity during atrial systole. This was associated with notching in the umbilical vein. The ductus venosus index is an angle-independent measurement from which right ventricular preload may be evaluated.     

Doppler ultrasound measurements in the central circulation of anesthetized fetal sheep during obstruction of umbilical-placental blood flow.

OBJECTIVE: To establish by Doppler ultrasound the effects of acute blockage of umbilical cord vessels on the fetal central circulation. DESIGN: Experimental study in anesthetized pregnant sheep. METHODS: In 11 anesthetized pregnant sheep (0.66 of gestation), Doppler velocity profiles and/or venous flow rates were recorded in the ductus venosus, the fetal aorta, the umbilical arteries and the umbilical vein. This involved three phases. In Phase 1, the abdominal wall was closed (n = 9); Phase 2 was during fetoscopy after laparotomy (n = 8); Phase 3 was after coagulation of one of the umbilical arteries (n = 10). As an additional intervention in six fetuses, the umbilical cord was clamped for 5-15 s while blood flow velocity changes in the ductus venosus were observed. RESULTS: There were no significant differences between Doppler recordings in Phases 1 and 2. During Phase 3, the pulsatility index of the aorta and of the coagulated umbilical artery increased significantly. The umbilical vein blood flow rate was significantly reduced from a median of 408 (range, 243-575) mL/min/kg in Phase 1 to a median of 173 (range, 107-426) mL/min/kg in Phase 3, but the blood flow rate in the ductus venosus (median, 94; range, 56-148 mL/min/kg vs. median, 92; range, 33-237 mL/min/kg) remained unchanged. The ductus venosus/umbilical vein ratio increased from a median of 0.22 (range, 0.13-0.41) to 0.56 (range, 0.17-0.97) (P < 0.05). Compression of the cord (5-15 s) immediately reduced the time averaged maximum velocity in the ductus venosus from a mean of 51 (standard deviation, 11) cm/s to 20 (standard deviation, 6) cm/s (P < 0.001) without significant changes of the velocity profile. However, the pulsatility index increased from a mean of 0.55 (standard deviation, 0.19) to 1.89 (standard deviation, 0.73) (P < 0.001). CONCLUSION: Central venous flows in anesthetized fetal sheep are unaffected by laparotomy and hysterotomy. Obliteration of one umbilical artery increases the ductus venosus/umbilical vein volume flow (mL/min/kg) ratio. Compression of the umbilical cord shifts down blood flow velocity profiles in the ductus venosus, and the pulsatility index thus increases.     

Ductus venosus blood flow velocity characteristics of fetuses with single umbilical artery.

OBJECTIVES: Sonographic Doppler evaluation of the fetal ductus venosus has been proved to be useful in the evaluation of fetal cardiac function. The aim of this study was to investigate the ductus venosus blood flow profile in fetuses with single umbilical artery and to correlate it with the umbilical cord morphology. METHODS: Fetuses at >20 weeks' gestation with single umbilical artery who were otherwise healthy were consecutively enrolled into the study. The sonographic examination included evaluation of the following Doppler parameters: umbilical artery resistance index, maximum blood flow velocity of the ductus venosus during ventricular systole (S-peak) and atrial contraction (A-wave), ductus venosus time-averaged maximum velocity (TAMXV), and pulsatility index for veins (PIV). The cross-sectional area of the umbilical cord and its vessels were measured in all cases. The Doppler and morphometric values obtained were plotted on reference ranges. RESULTS: A total of 88 fetuses with single umbilical artery were scanned during the study period. Of these 52 met the inclusion criteria. The S-peak velocity, A-wave velocity, and TAMXV were below the 5th centile for gestational age in 57.7%, 59.6%, and 57.7% of cases, respectively. The PIV was within the normal range in 80.1% of cases. The umbilical vein cross-sectional area of fetuses with single umbilical artery was above the 95th centile for gestational age in 34.6% cases. CONCLUSIONS: The ductus venosus blood flow pattern is different in fetuses with single umbilical artery from that in those with a three-vessel cord. This difference may be caused in part by the particular morphology of umbilical cords with a single artery.     

Combination of fetal Doppler velocimetric resistance values predict acidemic growth-restricted neonates.

OBJECTIVE: This study was undertaken to determine the efficacy of combination Doppler velocimetric resistance values of the umbilical artery and ductus venosus in predicting growth-restricted neonates with acidemia. METHODS: This retrospective case-control study included 61 gravidas complicated by intrauterine growth restriction with acidemia and 65 control pregnancies. The Doppler velocimetric resistance values obtained from the growth-restricted and control fetuses were in turn compared with the median values derived from another 192 normal pregnancies to adjust the biometric bias due to gestational age. RESULTS: Based on the pulsatility index of the umbilical artery and pulsatility index for the vein of the ductus venosus, the areas under the receiver operating characteristic curves were 0.7992 and 0.6749, respectively, for predicting growth-restricted neonates with acidemia. With a combination of the pulsatility indices of the umbilical artery and the pulsatility indices for the vein of the ductus venosus, the predictive accuracy of the growth-restricted neonates with acidemia increased, with sensitivity of 0.79 and specificity of 0.79 and an area under the receiver operating characteristic curve of 0.8441. CONCLUSIONS: Compared with single-vessel assessment, combining the pulsatility indices of the umbilical artery and the pulsatility indices for the vein of the ductus venosus provides the greatest accuracy in predicting growth-restricted neonates with acidemia.     

Absence of the ductus venosus: report of 10 new cases and review of the literature.

OBJECTIVE: To assess the clinical significance of the absence of the ductus venosus. DESIGN: A retrospective study with a review of the literature. METHODS: The archives of our ultrasound laboratory and the English literature were searched for cases with a prenatal diagnosis of absence of the fetal ductus venosus. RESULTS: Between 1985 and 2000, 10 fetuses were diagnosed in our center as having absence of the ductus venosus. The review of the literature revealed 23 cases. Three main patterns of abnormal venous circulation were documented: (1) umbilical vein bypassing the liver and connecting directly to the right atrium (46%); (2) umbilical vein bypassing the liver and connecting to the inferior vena cava mostly through one of the iliac veins (25%); (3) umbilical vein connecting to the portal circulation without giving rise to the ductus venosus (21%). Major anomalies, including chromosomal aberrations, were found in 8/33 (24%) cases. Hydrops developed in 11/33 (33%) cases. Twenty fetuses with isolated absence of the ductus venosus were delivered, and 5 (20%) died. The portal vein was found to be absent in half of the infants examined after birth. CONCLUSIONS: Our results and the review of literature suggest that absence of the ductus venosus is associated with a high incidence of fetal anomalies and adverse outcomes, including associated malformations, chromosomal aberrations, in utero heart failure and absence of the portal vein. Heart failure and absence of the portal vein seem particularly frequent when absence of the ductus venosus is associated with a connection of the umbilical vein to either the inferior vena cava or the right atrium.     

Staging of intrauterine growth-restricted fetuses.

OBJECTIVE: The purpose of this study was to evaluate the value of cardiovascular, ultrasonographic, and clinical parameters for developing a staging classification of intrauterine growth-restricted (IUGR) fetuses delivered at 32 weeks or earlier. METHODS: Intrauterine growth restriction was defined as the presence of an estimated fetal weight below the 10th percentile. Intrauterine growth-restricted fetuses were staged according to the following parameters, with the presence of any 1 parameter in a stage placing the fetus in that stage: stage I, an abnormal umbilical artery or middle cerebral artery pulsatility index; stage II, an abnormal middle cerebral artery peak systolic velocity, umbilical artery absent/reversed diastolic flow, umbilical vein pulsation and an abnormal ductus venosus pulsatility index; and stage III, reversed flow at the ductus venosus or reversed flow at the umbilical vein, an abnormal tricuspid E wave (early ventricular filling)/A wave (late ventricular filling) ratio, and tricuspid regurgitation. Each stage was divided into A (amniotic fluid index [AFI] <5 cm) and B (AFI >5 cm). The presence of maternal abnormalities was also reported. RESULTS: Seventy-four IUGR fetuses delivered at 32 weeks or earlier were included. Gestational age at delivery was greater in stage I fetuses compared with the other stages. Birth weight decreased with advancing stages. Stage III fetuses had the lowest AFI. There was a direct correlation between the severity of staging and both perinatal mortality and mortality occurring between 20 weeks' gestation and before the neonates were discharged from the hospital (P < .05). CONCLUSIONS: The staging system proposed here may allow comparison of outcome data for IUGR fetuses and may be valuable in determining more timely delivery for these high-risk fetuses.     

The anatomy of the umbilical, portal and hepatic venous systems in the human fetus at 14-19 weeks of gestation.

BACKGROUND: Ultrasound imaging of the fetal ductus venosus is becoming increasingly commonplace in clinical practice. The true anatomical relationships of the fetal umbilical and portal venous systems have not been clearly defined due to paucity of published data on the relevant anatomy. This has led to confusing terminology when describing the fetal umbilical, portal and hepatic circulations. The aim of the present study was to examine and document the anatomy of the umbilical, portal and hepatic venous systems and to propose a standardized nomenclature. METHODS: This was a prospective study on 11 fetuses obtained from medical termination of pregnancies between 14 and 19 weeks of gestation. The liver was microdissected to expose the branching pattern and anatomical relations of the umbilical, portal and hepatic venous systems. RESULTS: A wide L-shaped venous confluence at the terminal end of the umbilical vein, termed the portal sinus, was identified. The portal sinus was connected to the right and left hepatic lobes, by the right and left intrahepatic portal veins, respectively. The extrahepatic portal vein drained into the portal sinus just before the origin of the right intrahepatic portal vein. The ductus venosus, a branchless straight vessel, originated from the portal sinus and ascended steeply in the direction of the diaphragm. Numerous small vessels draining the liver converged into three main hepatic veins, which open into the subdiaphragmatic vestibulum. CONCLUSION: Based on detailed sequential anatomical dissection and clear illustrations, the present study documents the anatomy of the umbilical, portal and hepatic venous systems. Taking into account the embryological origin of the vessels, a new anatomically appropriate and simplified nomenclature of these venous systems is proposed. In clinical practice, the consistent use of the suggested terminology would allow collection of comparable data between units and enable operators to be confident of which vessels they are sampling by Doppler ultrasound.     

Changes in fetoplacental vessel flow velocity waveforms following maternal administration of betamethasone.

OBJECTIVE: To determine the timing of the onset of the umbilical artery flow velocity waveform changes following maternal administration of betamethasone in pregnancies complicated by umbilical artery absent end-diastolic flow, and to explore whether these changes are associated with flow velocity waveform changes in other fetoplacental vessels. SUBJECTS AND METHODS: This was a prospective study of 12 women with pregnancies complicated by umbilical artery absent end-diastolic flow. Flow velocity waveforms were recorded from the umbilical artery, fetal middle cerebral artery, renal artery, aorta and ductus venosus, before and after maternal betamethasone administration, using real-time pulsed wave Doppler. RESULTS: In all 12 pregnancies, the administration of maternal betamethasone was followed by the return of end-diastolic flow within 24 h. End-diastolic flow was first observed at 4 h and was present in all women studied at 8 h. In addition, there was a statistically significant decrease in the pulsatility index in the fetal aorta at 8 h and the middle cerebral artery at 24 h. No change was observed in the ductus venosus or the renal artery flow velocity waveforms. CONCLUSION: The findings suggest that, in pregnancies complicated by absent end-diastolic flow in the umbilical artery, maternally administered betamethasone induces a return in umbilical artery end-diastolic flow as early as 4 h, along with widespread vasodilatation throughout the fetoplacental vasculature.     

Prenatal diagnosis of abnormal course of umbilical vein and ductus venosus agenesis: Report of three cases

Ductus venosus connecting the portal and embryonic venous circulation into the inferior vena cava has a crucial role in fetal circulation. The absence of ductus venosus is a rare anomaly, in which the umbilical vein connection to the venous system may be extrahepatic, bypassing the liver or intrahepatic via the portal venous system. We report three cases of ductus venosus agenesis with associated anomalies. In two of them the connection was directly to the right atrium, whereas the umbilical vein drained to the left internal iliac artery in the third case. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2012;     

Longitudinal changes in the ductus venosus, cerebral transverse sinus and cardiotocogram in fetal growth restriction.

OBJECTIVE: To evaluate the changes in flow velocity waveforms in the transverse cerebral sinus in growth-restricted fetuses and to correlate these changes with (1) flow velocity waveforms in the ductus venosus and (2) changes in computerized analysis of the fetal cardiotocogram. DESIGN: Fetuses between 22 and 37 weeks' gestation with an estimated fetal weight below the fifth centile were included in this prospective longitudinal study. Doppler measurements of the umbilical artery, descending aorta, middle cerebral artery, transverse cerebral sinus and ductus venosus were recorded. Fetal heart rate was analyzed by a computer system according to the Dawes-Redman criteria. RESULTS: We measured a significant correlation between pulsatility index in the cerebral transverse sinus and in the ductus venosus over the study period and at delivery. There was a negative correlation between these indices and short- and long-term variability of the fetal heart rate. There was a parallel increase in pulsatility in the ductus venosus and the transverse cerebral sinus. These changes were inversely correlated with fetal heart rate variability and preceded fetal distress. CONCLUSION: Cerebral venous blood flow in IUGR fetuses may be a useful additional investigation to discriminate between fetal adaptation and fetal decompensation in chronic hypoxemia.     

An unusual anomalous intrahepatic connection between the left portal vein and internal mammary veins

Persistent embryonic portal vessels such as the umbilical vein or ductus venosus are occasionally encountered in the adult on ultrasound examination of the liver. These vessels must be identified and distinguished from the normal intrahepatic portal and hepatic veins. Recently, we have found another vein that, like the ductus venosus and persistent umbilical vein, is also a large intrahepatic portal vessel that is not a normal component of the hepatic vasculature. This anomalous vein originated from the left portal vein and traversed the liver parenchyma without branching to reach the anterior-superior liver margin, serving as an intrahepatic portal-systemic shunt by directly connecting the left portal vein and the internal mammary veins.     

正常孕10～19周胎儿静脉导管彩色血流频谱的初步探讨

目的探讨经腹彩色多普勒超声获取10～19周胎儿静脉导管血流频谱的正确采样及检测方法并建立其阻力指数（RI）、搏动指数（PI）、心室收缩期峰值流速与心房收缩期最低流速比值（S／A）的正常参考值范围；探讨生理性零或反向房收缩（RA）波在正常10～14周胎儿静脉导管中的发生率。方法随机选取111例孕10～19周的正常单胎孕妇，在不校正测量角度的情况下进行胎儿静脉导管血流频谱检测，对血流参数RI、PI和S／A值与孕周进行相关和回归分析。结果静脉导管的血流参数值随着胎龄的增加而减低，其95％的参考值范围分别为R10．34～0．90、P10．21～1．32和S／A1．23～6．65；10～14周胎龄段的50例胎儿静脉导管血流频谱中未见零或RA波。结论应用经腹彩色多普勒超声对10～19周胎儿静脉导管进行血流动力学评价方法简单，结果准确，容易掌握；静脉导管血流参数RI、PI和S／A值随着胎龄的增加而减低，其参考值范围可进一步应用于对胎儿染色体畸形和严重心脏畸形的研究；10～14周正常胎儿静脉导管内是否存在生理性零或RA波有待于进一步研究。     

Normal values of fetal ductus venosus blood flow waveforms during the first stage of labor.

OBJECTIVE: To present normal values of fetal ductus venosus blood flow waveforms during the first stage of labor during and between contractions. MATERIALS AND METHODS: Seventy-eight women between the 37th and 41st weeks of gestation were included in the study. At distinct stages of cervical dilation, blood flow velocity waveforms of the fetal ductus venosus during and between contractions were visualized in fetuses with a normal non-stress test. The pulsatility index for veins, peak velocity index for veins and fetal heart rate were calculated off-line. The means +/- standard deviations (SD) during and between contractions were compared using the Wilcoxon test. RESULTS: Ductus venosus blood flow velocity waveforms were visualized during 331 contractions and 375 episodes of uterine quiescence in 74 of 78 fetuses (95%) during normal labor. The mean +/- standard deviation values of pulsatility and peak velocity indices for veins during contractions were 1.66 +/- 0.85 (median: 1.56, range: 0.29-4.69) and 1.46 +/- 0.65 (median: 1.34, range: 0.26-3.13), respectively. Between contractions the values were 0.48 +/- 0.19 (median: 0.46, range: 0.14-1.00) for the pulsatility index and 0.44 +/- 0.18 (median: 0.42, range: 0.14-1.00) for the peak velocity index for veins. These differences during and between contractions were highly significant (P-value < 0.0001), whereas the fetal heart rate showed no significant differences. CONCLUSION: There are significant differences in fetal ductus venosus blood flow waveforms during and between labor contractions. Further studies should evaluate whether these normal values of the fetal ductus venosus are beneficial for risk evaluation in fetuses with an abnormal non-stress test and/or intrauterine growth restriction.     

Qualitative venous Doppler waveform analysis improves prediction of critical perinatal outcomes in premature growth-restricted fetuses.

BACKGROUND: Our aim was to test the hypothesis that qualitative ductus venosus and umbilical venous Doppler analysis improves prediction of critical perinatal outcomes in preterm growth-restricted fetuses with abnormal placental function. METHODS: Patients with suspected intrauterine growth restriction (IUGR) underwent uniform fetal assessment including umbilical artery (UA), ductus venosus (DV) and umbilical vein (UV) Doppler. Absent or reversed UA end-diastolic velocity (UA-AREDV), absence or reversal of atrial systolic blood flow velocity in the DV (DV-RAV) and pulsatile flow in the umbilical vein (P-UV) were examined for their efficacy to predict critical outcomes (stillbirth, neonatal death, perinatal death, acidemia and birth asphyxia) before 37 weeks' gestation. RESULTS: Seventeen (7.6%) stillbirths and 16 (7.1%) neonatal deaths were observed among 224 IUGR fetuses. Forty-one neonates were acidemic (19.8%) and seven (3.1%) had birth asphyxia. Logistic regression showed that UA-AREDV had the strongest association with perinatal mortality (R(2) = 0.49, P < 0.001), stillbirth (R(2) = 0.48, P < 0.001) and acidemia (R(2) = 0.22, P = 0.002) while neonatal death was most strongly related to DV-RAV and P-UV (R(2) = 0.33, P = 0.007). UA waveform analysis offered the highest sensitivity and negative predictive value and DV-RAV and P-UV had the best specificity and positive predictive values for outcome prediction. Overall, DV-RAV or P-UV offered the best prediction of acidemia and neonatal and perinatal death irrespective of the UA waveform. In fetuses with UA-AREDV, prediction of asphyxia and stillbirth was significantly enhanced by venous Doppler. CONCLUSION: Prediction of critical perinatal outcomes is improved when venous and umbilical artery qualitative waveform analysis is combined. The incorporation of venous Doppler into fetal surveillance is therefore strongly suggested for all preterm IUGR fetuses.     

Retrograde net blood flow in the aortic isthmus in relation to human fetal arterial and venous circulations.

OBJECTIVES: To characterize changes in the human fetal arterial and venous circulations associated with retrograde aortic isthmus net blood flow. METHODS: Study groups consisted of fetuses with placental insufficiency and/or fetal growth restriction and either antegrade (Group 1; n = 18) or retrograde (Group 2; n = 11) net blood flow in the aortic isthmus. The control group comprised 31 fetuses in uncomplicated pregnancies. Pulsatility indices of the umbilical, middle cerebral and proximal pulmonary arteries and the descending aorta, and pulsatility indices for veins of the ductus venosus and inferior vena cava were calculated. Right and left ventricular fractional shortenings were ascertained. The coronary artery blood flow was visualized and the presence of tricuspid regurgitation was noted. RESULTS: In the study groups, the umbilical artery and descending aorta pulsatility indices were significantly higher (P < 0.05), and those of the middle cerebral artery lower (P < 0.001), than in the control group, with no difference between the two study groups. The proximal pulmonary artery pulsatility index was significantly higher in Group 2 (P < 0.001) than in Group 1 and the control group. In Group 2, the right ventricular fractional shortening was significantly lower (P < 0.01) than in Group 1. Coronary artery blood flow was visualized significantly more often (P < 0.03) and tricuspid regurgitation was present more frequently (P < 0.003) in Group 2 than in Group 1. In Group 2, the ductus venosus pulsatility index for veins was significantly higher than in Group 1 (P < 0.01) and the control group (P < 0.01), with no difference in the inferior vena cava pulsatility index for veins. CONCLUSIONS: Fetuses with retrograde aortic isthmus net blood flow demonstrate a rise in right ventricular afterload and increased pulsatility in ductus venosus blood velocity waveforms.     

Middle cerebral artery Doppler in fetuses with transposition of the great arteries.

OBJECTIVE: A previous anthropometric study has shown that neonates with transposition of the great arteries have a smaller head circumference and intracranial volume, which may be related to a lower oxygen content of blood delivered to the head and upper extremities. The aim of this study was to compare Doppler blood flow velocity waveforms in fetuses with transposition of the great arteries with those in healthy fetuses. METHODS: Doppler blood flow velocimetry was performed in the middle cerebral artery, the umbilical artery, the aorta and the ductus venosus in a consecutive series of 23 fetuses with transposition of the great arteries between 36 and 38 weeks' gestation. The control group consisted of 40 healthy fetuses matched for gestational age. RESULTS: There was no significant difference in pulsatility indices in the umbilical artery, the aorta and the ductus venosus between fetuses with transposition of the great arteries and controls. The median middle cerebral artery pulsatility index in the group with transposition of the great arteries was 1.37 (range, 1.10-2.02) and was significantly lower than that in the control group (median, 1.68; range, 1.46-2.04) (P < 0.001, Mann-Whitney test). CONCLUSIONS: The lower pulsatility indices observed in the middle cerebral artery of fetuses with transposition of the great arteries may reflect a trend towards cerebral vasodilation. This phenomenon could be an indicator of hypoxemia and/or hypercapnia restricted to areas perfused by the preisthmus aorta and be related to the characteristics of the circulation in fetuses with transposition of the great arteries.     

静脉导管缺如并脐静脉异常连接产前超声心动图表现

目的 观察静脉导管缺如(ADV)并脐静脉肝内、肝外异常连接的产前超声心动图表现。方法 回顾性分析14胎ADV胎儿的超声心动图表现,观察心脏大小、功能变化,并随访临床预后。结果 ADV的检出率为0.12%(14/11 205),14胎中,5胎脐静脉与门静脉左支、1胎与门静脉右支相连;8胎脐静脉未与门静脉相连,而与肝外静脉系统相连,5胎直接连接于右心房,1胎直接连接于下腔静脉,1胎连接于肝右静脉,1胎连接于冠状静脉窦引流入右心房。结论 产前超声心动图能够明确诊断静脉导管缺如,且可以观察脐静脉肝内、肝外异常连接途径和管道内径。     

Cardiovascular hemodynamics and umbilical artery N-terminal peptide of proB-type natriuretic peptide in human fetuses with growth restriction.

OBJECTIVE: To test our hypothesis that human fetal N-terminal peptide of proB-type natriuretic peptide (NT-proBNP) secretion is increased in proportion to the severity of fetal cardiovascular compromise in intrauterine growth restriction. METHODS: This prospective cross-sectional study consisted of 42 growth-restricted fetuses who underwent Doppler ultrasonographic examination of cardiovascular hemodynamics within 7 days before delivery. Group 1 fetuses (n = 13) had normal umbilical artery (UA) velocimetry. Group 2 fetuses (n = 15) had abnormal UA and normal ductus venosus (DV) velocimetry. In Group 3 fetuses (n = 14), both UA and DV velocimetries were abnormal. At delivery, an UA blood sample was obtained for assessment of NT-proBNP. Normal values for UA NT-proBNP were determined in 49 neonates (control group) with uncomplicated pregnancy and delivery. RESULTS: Group 3 fetuses demonstrated greater (P < 0.05) UA and descending aorta pulsatility indices (PIs) and greater DV, left hepatic vein (LHV) and inferior vena cava PIs for veins (PIVs) than fetuses in Groups 1 and 2. Weight-indexed cardiac outputs and ventricular ejection forces were similar among the groups. Group 3 fetuses had higher (P < 0.05) UA NT-proBNP concentration than fetuses in Groups 1 and 2. In the control group, the 95(th) percentile value of UA NT-proBNP was 518 pmol/L. In Group 3, 13/14 neonates demonstrated abnormal UA NT-proBNP levels. The corresponding incidences were 4/13 and 7/15 in Groups 1 and 2. Significant positive correlations were found between UA, DV and LHV PIVs and UA NT-proBNP concentrations. CONCLUSION: In human fetal growth restriction, increased cardiac afterload and pulsatility in DV blood velocity waveform pattern are associated with elevated UA NT-proBNP concentrations.