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.     

Totally anomalous pulmonary venous connection and complex congenital heart disease: prenatal echocardiographic diagnosis and prognosis.

OBJECTIVE: The purpose of this study was to determine the accuracy of prenatal cardiac diagnosis, prognosis, and outcome of totally anomalous pulmonary venous connection (TAPVC) and to determine echocardiographic clues in the prenatal diagnosis of isolated TAPVC or TAPVC in association with other complex congenital heart disease (CHD). METHODS: We reviewed our 13-year experience of prenatal diagnosis of TAPVC. Thirteen fetuses were identified with the diagnoses of TAPVC. We systematically analyzed the individual pulmonary veins by color and pulsed Doppler imaging, the presence of a pulmonary venous confluence, the pulsed and color Doppler evaluation of the vertical vein, and sites of connections. Prenatal diagnosis was confirmed by postnatal echocardiography, cardiac catheterization, surgery, or autopsy. RESULTS: The mean gestational age at diagnosis of TAPVC was 26.3 weeks (range, 20-33 weeks). There were 8 fetuses with TAPVC and right isomerism, 3 fetuses with other associated CHD, and 2 with isolated TAPVC. There were 7 fetuses with supracardiac TAPVC, 4 with infracardiac TAPVC, and 2 with mixed TAPVC. Pulmonary vein color and pulsed Doppler data were available in 10 of 13 fetuses. The pulmonary venous confluence was visualized in all fetuses except 1. The vertical vein was visualized in all fetuses. Five fetuses had suspected signs of obstruction. The diagnosis was confirmed postnatally or at autopsy in 12 cases. Eight patients underwent surgery; 6 died, and 2 were alive. Two patients had compassionate care and died; 3 pregnancies were terminated. CONCLUSIONS: It is possible to diagnose accurately complex CHD, including the pulmonary venous connections. When diagnosed prenatally, TAPVC carries a poor prognosis.     

Venous pulsation in the fetal left portal branch: the effect of pulse and flow direction.

OBJECTIVE: To determine whether the waveform in the left portal branch is reciprocal to the waveform found in the ductus venosus and umbilical vein due to difference in pulse direction compared to flow. METHODS: Ten fetuses (gestational age, 18-33 weeks), six with intrauterine growth restriction, three with non-immune hydrops and one with sacrococcygeal teratoma, were examined using ultrasound imaging and pulsed Doppler. Techniques were adjusted to record simultaneously the waveform from neighboring sections of the veins, relate wave components to each other and determine degree of pulsatility. The corresponding vessel diameters were determined. ANOVA with t-test or Wilcoxon signed rank test was used to compare paired measurements. RESULTS: Pulsation in the left portal branch was noted in all fetuses. The pulsatility index was higher than in the umbilical vein (P = 0.005) and the diameter smaller (P = 0.001). In the left portal branch the atrial contraction wave appeared as a velocity peak while there was a nadir during ventricular systole. Simultaneous recordings showed that the waveform was reciprocal to that found in the ductus venosus and umbilical vein. In three cases an augmented pulsatility represented a pendulation of blood in the left portal branch with time-averaged velocity near zero. CONCLUSIONS: The velocity waveform recorded in the left portal vein is an inverse image of that in the ductus venosus, proving that pulse wave and blood flow run in the same direction in the left portal vein. Low compliance (i.e. small diameter) is probably a main reason for the high incidence of pulsation in this vein. Time-averaged velocity near zero recorded in three fetuses indicates that this area acts also as a watershed.     

Changes in pulmonary venous Doppler parameters in fetal cardiac defects.

OBJECTIVES: Recent observations in pediatric cardiological studies have prompted discussion on the possible role of intrauterine pulmonary venous changes in neonatal and postoperative outcome of infants with congenital heart defects. This study analyzes changes of Doppler blood flow velocity waveforms in the pulmonary veins of fetuses with different cardiac defects. METHODS: Eighty fetuses (mean gestational age, 27 weeks) with prenatally diagnosed cardiac defects were classified into one of five groups: obstructed left atrium, other left ventricular outflow tract obstruction, right ventricular outflow tract obstruction, miscellaneous cardiac defects and total anomalous pulmonary venous drainage. Doppler examination of the pulmonary veins was performed and the time velocity integral (TVI), end-diastolic (A) velocity, and pulsatility index for veins (PIV) were compared with reference ranges. RESULTS: Fetuses with infradiaphragmatic total anomalous pulmonary venous drainage showed a continuous Doppler flow pattern instead of the typical pulsatile waveform pattern. In fetuses with obstructed left atrium and restrictive foramen ovale, a reversed A-velocity and increased PIV were found. In five of the eight fetuses with left outflow tract obstruction but patent mitral valve, PIV was increased. In the other groups there were no obvious changes in Doppler parameters. CONCLUSIONS: We suggest routine examination of the pulmonary veins with pulsed Doppler ultrasound in every fetus with a prenatally diagnosed heart defect. Such Doppler parameters could be used in future as cut-offs for the recently reported in-utero atrial septostomy to decompress an obstructed left atrium.     

Transesophageal Doppler echocardiographic assessment of pulmonary venous flow pattern in subjects without cardiovascular disease

This study was designed to assess pulmonary venous flow dynamics using transesophageal Doppler echocardiography. Under general anesthesia, we studied 54 surgical patients with no history or physical evidence of cardiac disorders. In all patients pulmonary venous flow was easily identified by transesophageal color flow mapping. Pulmonary venous flow pattern, which was obtained clearly in 85% (4654) of patients by transesophageal pulsed Doppler echocardiography, was tri- or quadriphasic. The first wave, which was often biphasic in elderly patients, occurred during ventricular systole (S wave). The second wave occurred in diastole during the early ventricular filling phase of mitral flow (D wave). The third wave was reverse flow toward the pulmonary vein during atrial contraction (A wave). The following variables were measured: the peak flow velocities of each wave (PFVs, PFVd, PFVa), and the ratio of PFVs to PFVd (PFV(S/D)). The PFVd correlated with age (r=?0.56, P<0.001), indicating age-related decrease. The PFV(S/D) correlated with age (r=0.61, p<0.001), indicating age-related increase. These results would indicate that the contribution of pulmonary venous flow during diastole to total pulmonary venous flow decreases with age. Our data suggest that age-related diastolic dysfunction of the left ventricle would affect pulmonary venous flow dynamics and that left atrial storage volume during ventricular systole would increase with age.     

Doppler systemic venous flow patterns: Changes in children with mild/moderate pulmonic stenosis

To determine the usefulness of systemic venous flow patterns in patients with mild/moderate right ventricular hypertension, 17 patients with isolated mild/moderate pulmonic stenosis and 17 age-matched normal children were evaluated with pulsed Doppler echocardiography. Tricuspid valve, superior vena caval, and hepatic vein pulsed Doppler recordings were obtained with simultaneous respirometry and electrocardiography. Peak velocities and velocity-time integrals were measured for Doppler signals corresponding with ventricular systole, ventricular diastole, ventricular end systole, and atrial systole. The groups were similar in weight, heart rate, tricuspid inflow Doppler echocardiograms, and cardiac indexes. Compared with normal subjects, patients showed changes in respiratory variation for some superior vena caval and hepatic vein indexes. In addition, hepatic vein measurements made at ventricular end systole were significantly lower and measurements made at atrial systole were significantly higher in patients than in normal subjects. These changes in systemic venous flow patterns may provide a sensitive indicator of early right-sided heart dysfunction.     

区域血流追踪法在超声诊断胎儿肺静脉异位引流中的应用价值

目的探讨区域血流追踪法在超声诊断胎儿肺静脉异位引流中的价值。 方法回顾性选取2015年1月至2019年12月在河北生殖妇产医院进行胎儿超声心动图检查，诊断为肺静脉异位引流的胎儿41例。超声检查胎儿肺静脉时，应用区域血流追踪法，即将肺组织大致分为4个区域，左侧前上部1/2肺野、左侧后下部1/2肺野、右侧前上部1/2肺野、右侧后下部1/2肺野，应用彩色血流技术对41例肺静脉异位引流胎儿4个区域内肺静脉分支进行追踪并定位，观察其近心端与左心房的关系及最终回流部位。 结果41例肺静脉异位引流胎儿，4个区域内肺静脉远端分支分别引流入左上肺静脉、左下肺静脉、右上肺静脉、右下肺静脉。36例完全型肺静脉异位引流胎儿4条肺静脉近心端均未汇入左心房，其中34例呈现左心房后方汇聚征。心上型25例肺静脉最终回流入上腔静脉；心内型7例中6例通过冠状静脉窦回流入右心房，1例直接回流入右心房；心下型2例肺静脉回流入门静脉窦；混合型2例，1例左侧肺静脉汇入上腔静脉，右侧肺静脉汇入下腔静脉，1例左侧肺静脉汇入上腔静脉，右侧肺静脉回流入右心房。5例部分型肺静脉异位引流胎儿，1例右上肺静脉直接回流入右心房，2例右上肺静脉回流入上腔静脉，1例右上、右下肺静脉直接回流入右心房，1例左肺静脉变异为3支，最上支经无名静脉回流入上腔静脉。 结论应用区域血流追踪法可使肺静脉分支检查更全面，定位更加精确，有助于提高胎儿肺静脉异位引流的诊断准确性。     

Partial and total anomalous pulmonary venous connection in the fetus: two-dimensional and Doppler echocardiographic findings.

OBJECTIVE: Prenatal diagnosis of total (TAPVC) or partial (PAPVC) anomalous pulmonary venous connection in isolation or associated with other cardiac disease is important for appropriate prenatal counseling and perinatal management. We sought to assess the echocardiographic clues to the fetal diagnosis of TAPVC and PAPVC in a cohort of affected fetuses. METHODS: We retrospectively reviewed 29 fetal echocardiograms performed in 16 pregnancies with fetal TAPVC or PAPVC, systematically analyzing heart chamber size, presence of a confluence behind the left atrium or of a vertical vein, and Doppler flow patterns. RESULTS: Prenatal diagnosis was made at a mean gestational age of 27 +/- 7 weeks. TAPVC was found in 11 cases; five cases for each of supracardiac and infracardiac types and one mixed type. PAPVC was diagnosed in five fetuses, four of which had scimitar syndrome. Ten fetuses had an additional major cardiac defect, including hypoplastic left heart syndrome and right atrial isomerism. In three cases the prenatal diagnosis was only made at follow-up assessment. Among TAPVC cases, visualization of a confluence behind the left atrium (10/11) and a vertical vein (11/11) were the most consistent echocardiographic clues. Dextrocardia and a small right pulmonary artery suggested scimitar syndrome. The diagnosis was confirmed postnatally or at autopsy in 12 cases. In six fetuses with TAPVC and obstruction confirmed postnatally, continuous turbulent flow in the vertical vein and monophasic continuous flow in the pulmonary veins were demonstrated by color and spectral Doppler. CONCLUSIONS: Fetal echocardiography permits prenatal diagnosis of TAPVC or PAPVC. Spectral and color Doppler provide clues to the presence of an obstructed pulmonary venous pathway.     

Usefulness of Doppler waveform analysis before performing a complex procedure using femoral venous access

Ultrasonography is a well‐defined and widely accepted technique in the settings of interventional procedures requiring peripheral venous access, either for the confirmation of the vein patency (with the compression test) or for guiding needle insertion. This report describes a case of unsuccessful guidewire passage through the right iliac vein in spite of successful ultrasonography‐guided puncture of the femoral vein. On repeat duplex ultrasonography, the Doppler waveform showed a continuous pattern without respiratory phasicity, which was consistent with proximal venous occlusion. Venous Doppler signal waveform analysis can be helpful for ensuring downstream patency when planning long‐distance catheterization via femoral venous access.     

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.     

In utero diagnosis of obstructed supracardiac total anomalous pulmonary venous connection in a patient with right atrial isomerism and asplenia.

We describe a rare case of right atrial isomerism, levocardia, right-side stomach, obstructed supracardiac total anomalous pulmonary venous connection, double outlet right ventricle with complete atrioventricular septal defect and absent spleen. From the pulmonary venous confluence behind the atrium an ascending as well as a descending vertical vein communicated with the systemic venous system in the supracardiac as well as the infracardiac position. The pulsed and color Doppler examination of the individual pulmonary veins as well as of the vertical vein helped in making the diagnosis of obstructed total anomalous pulmonary venous connection. The diagnosis was made by fetal echocardiographic examination at 22 weeks of gestation and confirmed on postnatal echocardiography, cardiac catheterization, and at surgery.     

超声心动图诊断胎儿完全型肺静脉异位引流

目的 探讨胎儿完全型肺静脉异位引流(TAPVC)产前诊断线索及超声心动图特征.方法 回顾性分析于我院经超声诊断并经尸体检查或出生后超声心动图证实的14胎TAPVC胎儿的二维及多普勒图像的特征.结果 产前诊断12胎TAPVC,其中心上型9胎,心内型2胎,心下型1胎.TAPVC的产前诊断线索及超声心动图特征:二维超声四腔心切面未显示肺静脉角,左心房后壁光滑;左心房后壁与降主动脉间距离增大;可见共同肺静脉腔和垂直静脉.产前超声心动图漏诊2胎,经出生后超声心动图证实均为心内型TAPVC.14胎TAPVC中,4胎伴肺静脉引流途径梗阻.结论 胎儿超声心动图可诊断TAPVC并准确分型;脉冲和彩色多普勒超声可显示肺静脉回流途径梗阻.     

Ductus venosus Doppler study in fetuses with homozygous alpha-thalassemia-1 at 12 to 13 weeks of gestation.

OBJECTIVE: Fetuses affected by homozygous alpha-thalassemia-1 are anemic from the first trimester of pregnancy. We investigated ductus venosus Doppler velocimetry in these affected fetuses at 12-13 weeks of gestation. DESIGN: Prospective observational study. SUBJECTS: Women referred for the prenatal diagnosis of homozygous alpha-thalassemia-1 before 14 weeks of gestation. METHODS: All fetuses underwent pulsed Doppler investigations following color flow mapping at 12 or 13 weeks of gestation. Homozygous alpha-thalassemia-1 was diagnosed by DNA or hemoglobin study. The ductus venosus Doppler indices--Vmax (peak velocity during ventricular systole), Vmin (minimum forward velocity during atrial systole), TAMX (time-averaged maximum velocity), PIV (pulsatility index for veins, Vmax-Vmin/TAMX), PLI (preload index, Vmax-Vmin/Vmax) and Vmax/Vmin ratio--were compared between the affected fetuses and fetuses unaffected by homozygous alpha-thalassemia-1. RESULTS: Between June 1998 and October 1999, 102 eligible women were recruited. Fetal ductus venosus Doppler study was successful in 96 pregnancies (94%). Of these, 20 fetuses were affected by homozygous alpha-thalassemia-1. None of them showed hydropic changes at the time of Doppler study. The affected fetuses had significantly higher ducts venosus Vmax (30% increase), Vmin (50% increase) and TAMX (20% increase) and significantly lower Vmax/Vmin ratio, PIV and PLI values. CONCLUSION: Fetuses affected by homozygous alpha-thalassemia-1 at 12-13 weeks had increased forward flow velocities in the ductus venosus throughout the cardiac cycle. The increase of venous return is consistent with our previous report of cardiac dilatation and an increase of cardiac output in the affected fetuses at this stage as a compensatory mechanism for anemia and hypoxia. However, extensive overlap of the ductus venosus Doppler indices between affected and unaffected fetuses precludes its use in predicting anemia at 12-13 weeks.     

彩超观察胎儿肺静脉在产前二级筛查中的应用

目的探讨彩超观察胎儿肺静脉在产前二级筛查中的应用价值。方法对113例妊娠20～34周孕妇进行常规胎儿产前彩超筛查,重点观测胎儿肺静脉及其血流参数:S波(心室收缩期峰值流速)、D波(心室舒张期峰值流度)、A波(心房收缩期流速),计算S/D值和PVI值〔峰值血流指数,PVI=(S-A)/D〕。将其中100例正常胎儿列入对照组(A组),对比分析其4条肺静脉血流参数;将13例产前彩超筛查有先天性心脏病(CHD)的胎儿列入实验组(B组),比较两组的右下肺静脉血流参数。结果 A组4条肺静脉的S波、D波、S/D及PVI差异均有统计学意义(P<0.05),多数A波表现为正向波,但差异无统计学意义(P>0.05)。B组与A组S波、D波及S/D无显著差异(P>0.05),B组A波均值反转,与A组比较差异显著(P<0.05),PVI明显高于A组(P<0.05)。结论观测肺静脉A波、PVI可作为CHD产前筛查的一项指标。在测量肺静脉血流参数时应选取某一条固定的肺静脉进行测量。     

Atypical ductus venosus blood flow pattern in fetuses with severe tricuspid valve regurgitation.

We observed seven cases of atypical ductus venosus (DV) blood flow velocity waveform pattern with impairment of systolic forward flow resulting in a notch or a significant reduction in peak velocity during the S-wave in systole. All affected fetuses had severe tricuspid valve regurgitation associated with congestive heart failure and/or cardiac malformations. The decrease in venous systolic forward flow modulates the venous pulsatility indices towards more favorable values and should be considered when fetuses with tricuspid regurgitation are followed by Doppler assessment of the DV. Detection of these changes in the DV flow profile should prompt detailed color Doppler echocardiography with special emphasis on right atrioventricular valve regurgitation.     

Quantitative assessment of right ventricular function using doppler tissue imaging in fetuses with and without heart failure.

BACKGROUND: Previous reports have established the use of Doppler tissue imaging (DTI) for noninvasive assessment of ventricular function, but the technique has not been validated for diagnosis of fetal cardiac failure. OBJECTIVE: The purpose of this study was to assess right ventricular (RV) function in fetuses with heart failure using DTI. METHODS: In all, 43 fetuses (36 control, 7 heart failure) were assessed using pulsed Doppler echocardiography combined with DTI. RV peak myocardial velocities during early diastole (Ea), atrial contraction, and systole were measured; and tricuspid peak velocities during early diastole (E) and atrial contraction. The ratio of E/Ea was used as an index of filling pressure were measured. From DTI, a Doppler-derived index of combined systolic/diastolic myocardial performance (DTI-Tei index) was measured. RESULTS: Compared with control fetuses, the mean Ea was significantly lower and the mean E was significantly higher in fetuses with heart failure, although these parameters did overlap between the 2 groups. The mean RV myocardial wall-motion velocity during atrial contraction, ratio of Ea/RV myocardial wall-motion velocity during atrial contraction, and RV myocardial wall-motion velocity during systole did not differ between the 2 groups. Compared with control fetuses, the mean E/Ea was significantly higher (9.71 +/- 0.91 vs 6.20 +/- 0.97; P <.0001) and the mean DTI-Tei index was significantly greater (0.79 +/- 0.11 vs 0.55 +/- 0.05; P <.0001) in fetuses with heart failure. In addition, the DTI-Tei index z score was >2 in all fetuses with heart failure. CONCLUSIONS: This study demonstrated a clinically important application of DTI-derived tricuspid annular velocities in fetuses with heart failure. Although DTI velocities were not sufficiently sensitive to identify fetuses with heart failure versus control fetuses, DTI-Tei index and E/Ea were useful and sensitive indicators of global RV dysfunction.     

Color Doppler examination of the outflow tracts of the fetal heart: a technique for identification of cardiovascular malformations.

The objective was to describe a technique using color Doppler to identify the outflow tracts of the fetal heart by directing the ultrasound transversely through the fetal chest. One hundred second- and third-trimester control fetuses were examined with real-time and color Doppler ultrasound. The ultrasound beam was directed cephalad, in the same transverse plane used to image the four-chamber view, and the outflow tracts were examined. Four fetuses with abnormal cardiovascular anatomy were examined using the above approach, to study the anatomical relationships of the outflow tracts identified with color Doppler ultrasound in normal fetuses.When the ultrasound beam was directed immediately cephalad to the four-chamber view, the aorta was identified as it exited the left ventricle. Further movement of the ultrasound beam cephalad identified the following vessels in a single plane: the main pulmonary artery perpendicular to the ascending aorta; the left pulmonary artery branching from the main pulmonary artery; the full length of the ductus arteriosus; and the transverse arch of the aorta. The ascending aorta, main pulmonary artery, ductus arteriosus and transverse aortic arch were identified in 100% of fetuses. Four fetuses with abnormalities of the outflow tracts (aortic stenosis, aortic regurgitation, pulmonary stenosis and premature constriction of the ductus arteriosus) were imaged using this approach in which pathology was readily identified.This technique enables rapid identification of the outflow tracts in second- and third-trimester fetuses using color Doppler and accurately identifies abnormalities of these vessels.     

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.     

Qualitative and quantitative analysis of portal Doppler waveform and a novel factor of portal pulsatility: Systolic spike wave

Background We attempted to identify the physiologic circumstances associated with the portal Doppler waveform. Method The subjects were 98 patients: 42 had cirrhosis; 23, hepatitis; and 33, no liver disorder. We measured right portal venous peak velocity, minimum velocity, and hepatic arterial peak systolic velocity. Portal venous pulsatility was calculated as portal venous minimum velocity divided by portal venous peak velocity. We analyzed portal waveforms both qualitatively and quantitatively. Results Portal Doppler waveforms were classified as nonphasic, monophasic, biphasic, biphasic including spike wave, and triphasic. Portal waveforms were phasic in 84 subjects who had a mild systolic dip during the arterial systolic period. Markedly portal pulsatility (portal venous pulsatility<0.6) was present in only 7 subjects. A systolic spike wave corresponding to a hepatic arterial peak systolic wave was detected in 48 subjects. Hepatic arterial peak systolic velocity was significantly higher in the group with spike wave than in the group without it. Conclusion Although portal pulsatility is generally attributed to multiple factors, the present study has pointed out a new factor; transmission via the hepatic artery through the portal vein vasa vasorum. Hepatic venous drainage and hepatic arterial blood flow influence portal waveform.     

取样容积位置和大小变化对超声检测肺静脉血流的影响

目的评价取样容积位置和大小变化对肺静脉血流频谱的影响.方法 34例正常儿童为研究对象,取样容积(SV)取0.21cm、0.52cm、1.07cm、1.74cm,置于肺静脉左心房开口内0.5cm处,应用多普勒超声技术,分别记录右上、右下、左上及左下肺静脉血流频谱.结果清晰记录到肺静血流脉频谱的成功率分别为右上肺静脉32例(94.1%)、左上肺静脉18例(52.94%)、左下肺静脉9例(26.47%)、右下肺静脉6例(17.65%);四组间有显著性差异(P<0.01).取样容积取 0.21cm时,右上肺静脉血流收缩期峰值流速(S)、加速时间(SAT)、S波速度积分(SI)及舒张期峰值流速积分(DI)与SV取 0.52cm、1.07cm、1.74cm时的测值间有显著性差异(P<0.05),SV取0.52cm、1.07cm、1.74cm时各参数间无显著性差异(P>0.05).结论取样容积位置和大小变化对肺静脉血流参数的检测有影响;SV取0.21cm,置于右上肺静脉内可以比较清晰的显示肺静脉血流频谱.