Ruptured vertebrobasilar junction aneurysm associated with basilar artery fenestration

BACKGROUND: The goal of the study was to measure the blood flow parameters of the fetal internal jugular vein during the second half of normal pregnancy using Doppler ultrasound. METHODS: Jugular blood flow was analyzed in 95 normal singleton fetuses between 20 and 42 weeks gestation. Color and pulsed Doppler ultrasound was used to obtain jugular venous waveforms at the level of the mid-neck. Peak velocities, ratios of velocities, and time-averaged maximum velocities were measured. RESULTS: Jugular venous waveforms in healthy fetuses consist of three phases--the first forward peak occurs during ventricle systole; the second forward peak occurs during early diastole and the third peak occurs during atrial contraction. Forty-eight percent of the fetuses demonstrated absent flow during atrial contraction; 32% of fetuses demonstrated forward flow during atrial contraction and finally 20% of fetuses demonstrated flow reversal during atrial contraction. CONCLUSIONS: The reported jugular venous profile may serve as a foundation for future studies of jugular blood flow in high risk fetuses.     

Cardiotocogram compared to Doppler investigation of the fetal circulation in the premature growth-retarded fetus: longitudinal observations

It was our objective to compare computerized fetal heart rate analysis with blood flow velocity waveform analysis of the arterial and venous fetal circulation in intrauterine growth retardation. We report five illustrative cases with longitudinal observations of fetal Doppler findings and fetal heart rate between 23 and 32 weeks of gestation. Blood flow waveforms were recorded from the umbilical artery, middle cerebral artery, descending aorta, ductus venosus and inferior vena cava. Fetal heart rate was analyzed by a computer system according to the Dawes-Redman criteria. The time sequence of deterioration is described individually for each fetus. An abrupt increase in pulsatility of ductus venosus waveforms with loss of forward flow velocity during atrial contraction preceded abnormally low short-term variation of fetal heart rate. With advanced gestational age and concomitant maternal disease, we observed severe alterations of flow velocity waveforms within 12 h of normal Doppler measurements, which is in contrast to findings in the second trimester, in which severely abnormal venous waveforms were observed over a period of several weeks before intrauterine death occurred. In a fetus with terminally low short-term variation, normal venous waveforms indicated fetal well-being despite an abnormal cardiotocogram (CTG). We challenge the current concept that the CTG is the best available parameter to determine the optimal time for elective delivery of premature growth-retarded fetuses. Deterioration in ductus venosus blood flow seems to precede an abnormal CTG and thus heralds the need for delivery.     

Mental illness in homeless women: an epidemiological study in Munich, Germany

This longitudinal observational study evaluates the stage at which coronary flow can be visualized by color-coded and pulsed wave Doppler sonography in fetuses with normal cardiac anatomy. Fetal biometry, echocardiography and Doppler examination of the umbilical and middle cerebral arteries, ductus venosus, inferior vena cava and umbilical vein were performed in 109 cases. Fetuses were divided into five groups based on the Doppler examination of the umbilical artery, birth weight and the ability to visualize coronary blood flow. Coronary blood flow was identified in six of 55 fetuses with normal growth who had normal Doppler studies and perinatal outcome. In these, visualization of coronary blood flow was possible after 31 weeks' gestation at a median gestational age of 37 weeks. Coronary blood flow was also visualized in ten of 54 fetuses with severe intrauterine growth retardation and highly pathological flow velocity waveforms in all vessels soon after a significant increase of venous indices in the inferior vena cava and ductus venosus. In these cases, coronary blood flow was identified at a significantly earlier gestational age (median 27 weeks). These fetuses had a poor perinatal outcome (average birth weight less than 3rd centile, mortality rate 50%, significantly lower umbilical artery blood pH and Apgar scores after 1 and 5 min). Intrauterine fetal death occurred in five fetuses after a median of 3.5 days following visualization of coronary blood flow. Median coronary peak blood flow velocities in the right coronary artery were higher in intrauterine growth-retarded than appropriate-for-gestational-age fetuses.     

Changes of venous blood flow velocity waveforms in fetuses with supraventricular tachycardia

Studies in the fetal lamb have shown that atrial pacing beyond a rate of 300-320 beats/min may be associated with dramatic changes of venous blood velocity waveforms, an increase of venous pressure by up to 75%, hydrops, polyhydramnios and placental edema. The aim of our study was to determine the 'critical' heart rate frequency in the human fetus. In 11 fetuses (five with and six without hydrops) with supraventricular tachycardia, pulsed wave Doppler analysis of flow velocity waveforms of the inferior vena cava, the ductus venosus and the left hepatic vein were performed before and after drug treatment. In ten cases cardioversion was achieved by in utero antiarrhythmic drug therapy; in one case treated with digoxin and flecainide the supraventricular tachycardia was decreased to 160-190 beats/min with disappearance of hydrops. Before intrauterine treatment of supraventricular tachycardia, pulsatile reversal of blood flow in the inferior vena cava, ductus venosus and left hepatic vein was visible, with monophasic forward flow during systole and reversed flow during diastole in ten of 11 fetuses. One fetus with supraventricular tachycardia of 195 beats/min showed a normal biphasic forward flow pattern. During drug-induced sinus rhythm, a normal biphasic forward venous blood flow pattern was shown in all ten cases. In five cases pulsatile reversal was demonstrated during a drug-induced reduction of the heart rate from 280 to 210 beats/min and a normal biphasic forward flow velocity waveform appeared during supraventricular tachycardia below 210 beats/min.(ABSTRACT TRUNCATED AT 250 WORDS)     

Sex and crime: heterotrimeric G proteins in fungal mating and pathogenesis

The coronary circulation is the major determinant of myocardial oxygen balance which in turn is necessary for adequate cardiac function under a variety of conditions. Experiments in the fetal lamb suggest short-term functional coronary autoregulation in response to increase in afterload and acute hypoxemia. Long-term, acute-on-chronic hypoxemia is associated with a marked increase of maximal myocardial flow reserve suggesting coronary vascular angio-neogenesis during the period of chronic hypoxemia. In the human fetus, flow velocity waveforms from the coronary arteries may be obtained by color-coded and pulsed wave Doppler sonography in normally developed fetuses from 31 weeks of gestation onwards under favorable imaging conditions. Coronary blood flow may also be visualized in selected fetuses with intrauterine growth restriction, absent or reversed end-diastolic flow in the umbilical artery, cephalization of blood flow and abnormal flow patterns in the precordial veins and the umbilical vein. In these fetuses visualization of coronary blood flow may be possible as early as 26 weeks gestation and is consistently associated with a significant increase in the peak velocity index for veins in the ductus venosus. In this circulatory state, visualization of coronary blood flow is suddenly very easy. This "visualization threshold" may be a sign of maximal increase in coronary blood flow in an attempt to "spare" the fetal heart of hypoxemia. Although highly operator dependent, demonstration of coronary blood flow in intrauterine growth restriction identifies fetuses at high risk for intrauterine fetal death and postpartum circulatory failure.     

Doppler echocardiographic assessment of fetal blood flow redistribution during maternal hyperoxygenation

In a retrospective analysis of the standard protocols for fetal echocardiographic examination, 27 fetuses (mean gestational age 29 +/- 5.4 weeks) with ascites were evaluated. Fetal cardiomegaly (increased heart area/chest area ratio), the presence or absence of atrioventricular valve regurgitation, inferior vena cava and ductus venosus Doppler flow velocity and umbilical vein pulsation were evaluated quantitatively in a group of survivors and non-survivors. A statistically significant difference between the two groups was found for the presence of atrioventricular valve regurgitation (p = 0.003), and for cardiomegaly (p = 0.009). There was no statistical difference for the presence of abnormal venous flow and umbilical pulsation (p > 0.05). Abnormal venous Doppler flow velocities in the inferior vena cava and ductus venosus were observed more frequently than umbilical vein pulsation. The mean heart area/chest area ratios in the group of survivors and in the group of non-survivors were 0.34 +/- 0.09 and 0.48 +/- 0.08, respectively (p < 0.001). The mean gestational ages at the time of diagnosis of ascites in the groups of survivors and non-survivors were 33 +/- 3.3 weeks and 28 +/- 5.1 weeks, respectively (p < 0.05); the mean gestational ages at the time of delivery were 35.6 +/- 2.3 weeks and 33.3 +/- 4.9 weeks, respectively (p = 0.33). In terms of different echocardiographic features as well as the gestational age of the unborn patient with ascites, there is apparently no single indicator of a poor prognosis. Our results suggest that the prognosis is usually poor in a fetus with ascites, when cardiomegaly is detected, as well as the presence of tricuspid and mitral valve regurgitation. This is regardless of the type of venous flow and regardless of the etiology of the ascites.     

Closure of the ductus venosus in premature infants: findings on real-time gray-scale, color-flow Doppler, and duplex Doppler sonography

OBJECTIVE: Our objective was to use gray-scale, color-flow, and duplex Doppler sonography to study the anatomy, flow pattern, and time of closure of the ductus venosus in healthy premature infants. SUBJECTS AND METHODS: We prospectively examined the ductus venosus in 130 premature infants whom we divided into two groups: Group I comprised 27 neonates of gestational age 28-32 weeks, and group II comprised 103 neonates of gestational age 33-36 weeks. Neonates who had undergone umbilical vessel manipulation were excluded from the study. All examinations included gray-scale, color-flow, and duplex Doppler sonography. Patency, length, color flow, and Doppler characteristics of the ductus venosus were recorded. Neonates were examined 1-2 days after birth, 6-7 days after birth, and subsequently every 3-4 days until ductus closure was observed. The time of closure of the ductus for the two groups was compared using the chi-square test. RESULTS: The ductus venosus was patent during the initial examination in 128 of the 130 neonates. Doppler waveform was venous with little variation in velocity. Ductus length slightly exceeded 1 cm in both groups. We found a statistically significant difference in the percentage of infants having a patent ductus venosus after the initial examination: At 1 week after birth, ductus patency was shown in 85% of the infants in group I and in 56% of the infants in group II; at 2 weeks, the respective percentages were 42% and 14%; and at 3 weeks, 27% and 0%. CONCLUSION: The ductus venosus is patent 1-2 days after birth in virtually all premature infants. From 6 days after birth and onward, a significantly greater percentage of smaller premature infants (i.e., 28-32 weeks' gestational age) have a patent ductus venosus than do larger premature infants (i.e., 33-36 weeks' gestational age).     

Changes in blood velocities of fetal circulation in association with fetal heart rate abnormalities: effect of sublingual administration of nifedipine

Nifedipine has been used to treat hypertension in pregnancy, and does not influence fetal or uteroplacental circulations in patients with preeclampsia. A 29-year-old multi-gravid woman presented at 32 weeks' gestation with significant elevation of her blood pressure. After sublingual administration of nifedipine, the blood pressure decreased from 208/122 to 136/96 mm Hg at 30 minutes. In her growth-retarded fetus with abnormal flow velocity waveforms, pulsatility index values for middle cerebral artery and umbilical artery did not change; however, peak systolic velocities, end-diastolic velocities, and time-averaged mean peak velocities for these arteries became significantly elevated. Simultaneously, severe variable decelerations and late decelerations occurred. The adverse effect of nifedipine on fetal circulation might occur in a growth-retarded fetus with abnormal flow velocity waveforms.     

Reversed end-diastolic umbilical flow in a first-trimester fetus with congenital heart disease

Reversed end-diastolic umbilical artery velocities and a reduced chorionic sac were first seen at 10 weeks in a pregnancy subsequently showing a normal male karyotype on chorionic villi. Four weeks later Doppler studies demonstrated normal umbilical artery waveforms. At 20 weeks, ultrasound examination of the fetus revealed a mild pericardic effusion, hypoplastic righ heart with hypertrophic myocardium and a single umbilical artery, suggesting pulmonary atresia. After neonatal death, pathological studies confirmed pulmonary atresia. This case suggests that reversed end-diastolic umbilical flow in the first trimester may identify a subgroup of fetuses with a lethal abnormality (heart defect, severe intra-uterine retardation, aneuploidy or others).     

Transient increase in nuchal translucency thickness and reversed end-diastolic ductus venosus flow in a fetus with trisomy 18

In a twin pregnancy discordant for trisomy 18, the affected fetus at 13 weeks' gestation had an increased nuchal translucency thickness and reversed end-diastolic ductus venosus flow. At 20 weeks' gestation there was no nuchal edema and Doppler study of the central venous vessels demonstrated normal waveforms. The findings support the hypothesis that one of the mechanisms in the development of increased nuchal translucency is temporary cardiac strain.     

Cardiac flow after fetal blood sampling in normally grown and growth-retarded fetuses

The objective of this study was to evaluate the effect of fetal blood sampling on cardiac flow velocity waveforms. Flow velocity waveforms were measured from the ascending aorta and pulmonary artery immediately before and after fetal blood sampling in 29 normally grown and 12 growth-retarded fetuses. The latter group was characterized by abnormal Doppler indices in the umbilical artery and middle cerebral artery suggestive of uteroplacental insufficiency as the causative factor of the impaired growth. The flow velocity parameters studied were the peak velocity, the time to peak velocity, and the left and right cardiac output and their ratio. In normally grown fetuses, the peak velocity and right and left cardiac output values increased significantly after fetal blood sampling, while no significant changes were observed in the other indices considered. The gestational age at the time of the procedure was positively related to the amplitude of these changes. In growth-retarded fetuses, fetal blood sampling did not induce any significant increase in cardiac output or peak velocities, while in more than 50 per cent of the fetuses these Doppler indices decreased. The amplitude of the decrease was significantly related to the severity of acidosis in the umbilical vein. In conclusion, the cardiac haemodynamic response to fetal blood sampling differs between normally grown and growth-retarded fetuses. This difference may explain the higher rate of complications occurring in the latter group of fetuses after blood sampling.     

The head-to-abdomen circumference ratio: a reappraisal

Our objective was to assess the clinical significance of the sonographically derived head-to-abdomen circumference ratio in small-for-gestational-age (SGA) fetuses. The head-to-abdomen ratio was determined in 134 singleton SGA fetuses without ultrasound evidence of malformations at 26-40 weeks' gestation. Data were collected regarding antenatal surveillance, umbilical artery Doppler velocimetry and neonatal outcome. In SGA fetuses, the head-to-abdomen ratio, adjusted for gestational age, had a normal frequency distribution, positively skewed with regard to fetuses with normal birth weight. An elevated head-to-abdomen ratio was found in 56 SGA fetuses (42%), and was associated with increased perinatal mortality (odds ratio 3.27; 95% confidence internal 1.04-9.34), lower birth weight (1533 +/- 635 g vs. 2022 +/- 655 g, p < 0.0001) and lower gestational age at delivery (34 +/- 3.6 weeks vs. 36.3 +/- 3.6 weeks, p < 0.005). However, logistic regression revealed that the most powerful antenatal determinants of pregnancy outcome were Doppler velocimetry of the umbilical artery, followed by biophysical profile, while no independent correlation was found with the head-to-abdomen ratio. The existence of two distinct categories of SGA fetuses, 'symmetric' and 'asymmetric', remains uncertain. An elevated head-to-abdomen ratio is an adverse risk factor for pregnancy outcome. However, this parameter has no clearcut clinical value when umbilical artery Doppler velocimetry and biophysical antenatal testing are available.     

Effect of antenatal administration of thyrotrophin releasing hormone on fetal flow velocity waveforms

AIM: To determine whether antenatal administration of thyrotrophin releasing hormone (TRH), to promote lung maturation, alters blood flow through the fetal middle cerebral, umbilical artery, or ductus arteriosus and through the maternal uterine arteries. METHODS: The effect of transplacentally administered TRH on the fetal circulation was prospectively evaluated in 30 patients between 24 and 34 weeks' gestation. TRH (400 micrograms) was given to the mother intravenously either as a bolus or an infusion. Fetal effects were determined by measuring the maximum velocity and pulsatility index (PI) in middle cerebral artery, ductus arteriosus, uterine artery and umbilical artery Doppler waveforms. Measurements were made immediately before, and 10 and 60 minutes after maternal TRH administration. RESULTS: Intravenous injection of TRH had no significant effect on PI in the uterine, umbilical, or middle cerebral artery and the ductus arteriosus within 60 minutes of administration in either group. CONCLUSION: The antenatal use of TRH in conjunction with steroids for fetal lung maturity does not affect utero-placental or fetal haemodynamic variables, as measured by Doppler. These findings, therefore, do not support the suggestion that antenatal intravenous administration of TRH either as bolus or infusion may have immediate adverse vascular effects in the fetus.     

Step-wise lengthening for delayed repair of avulsion of the flexor pollicis longus

Congenital abnormalities of the umbilical venous system are rare. A case of fatal right congenital diaphragmatic hernia (CDH) in association with an anomalous umbilical vein bypassing the liver and directly entering the right atrium is presented. The ductus venosus was absent. Although much of the liver was within the right hemithorax, radiographs showed an apparently normal umbilical venous catheter (UVC) course, suggesting a normally positioned liver and mitigating against the diagnosis of CDH. Aberrant umbilical drainage, yielding a falsely normal appearing UVC course, may delay the diagnosis of CDH.     

Study of the use of vitamin K in neonates in France

Our objective was to assess flow velocity waveforms of the portal venous system of the anemic fetus prior to and immediately following intravascular transfusion. Color-guided pulsed Doppler was used to obtain flow velocity waveforms from the fetal portal vein in 14 anemic fetuses that were transfused in utero for rhesus alloimmunization The portal vein velocity pattern was defined as continuous when no change in velocity during the cardiac cycle was noted. It was defined as pulsatile when a deflection of the wave was present. The flow velocity waveforms were quantified by using the ratio between the peak (highest, H) and the nadir (lowest, L) velocities (H/L ratio). Fourteen intravascular transfusions were performed. Gestational age ranged from 19.5 to 35 weeks (mean +/- SD, 26.7 +/- 5.3 weeks). The hematocrit ranged from 5.9 to 31.2% (mean +/- SD, 20.3 +/- 9%) prior to transfusion; after transfusion it was between 24.8 and 56.7% (mean +/- SD, 42 +/- 10.4%). In six cases (43%) the waveforms were pulsatile prior to transfusion; in the other eight (57%) they were continuous. The pulsatile pattern was present following transfusion in 13 cases (93%, p < 0.05). The mean of the H/L ratio was 1.3 +/- 0.38 prior to transfusion and 2.0 +/- 0.86 after transfusion (p < 0.05). Because the portal vein has continuous non-pulsatile flow in the normal fetus, the presence of pulsatility in the waves of six anemic fetuses (43%) may suggest portal hypertension. Compared to normal fetuses, there was an increased number of cases with pulsation, and even more so after transfusion. The pattern corresponds to findings in children with portal hypertension.     

In utero ultrasonographic diagnosis of an aberrant umbilical vein associated with fetal hepatic hyperechogenicity

Intra-hepatic abnormalities of the fetal umbilical venous system are poorly documented and clinically not well understood. A case of routine ultrasound examination at 23 weeks' gestation demonstrating foci of hepatic hyperechogenicity and cardiomegaly is presented. Colour Doppler detected absence of flow in the ductus venosus and markedly increased blood flow through an aberrant channel connecting the umbilical vein with the right atrium. The pregnancy was terminated and anomalous venous drainage of the umbilical vein into an enlarged hepatic vein was found, as well as hepatic congestion and focal hepatic necrosis and calcifications. Incidental findings of fetal hepatic hyperechogenicities require colour Doppler investigation of the intra- and extra-hepatic venous systems. We propose that a thrombo-embolic mechanism may be involved in the pathogenesis of these lesions.     

Transient diabetes mellitus and peripheral insulin resistance following Tacrolimus intoxication in a child after renal transplantation

OBJECTIVE: Cord entanglement is a common complication of monoamniotic twins and it is associated with high perinatal mortality. Apart from preterm delivery, no treatment has previously been used to reduce the risks of this complication. We postulated that reducing amniotic fluid volume would stabilize fetal lie and reduce the risk of cord compression. STUDY DESIGN: Cord entanglement was documented in three cases of monoamniotic twins in the midtrimester. Sulindac was administered to the mother. Amniotic fluid index, fetal urine output, and umbilical artery and ductus arteriosus Doppler waveforms were investigated before and during treatment by use of real-time and pulsed Doppler techniques. RESULTS: Sulindac was associated with a dose-related reduction in amniotic fluid index and fetal urine production without alteration in fetal flow velocity waveforms. Fetal lie stabilized after commencement of treatment. All six twins were delivered with no complications. CONCLUSION: Medical amnioreduction with sulindac is a new management option in monoamniotic twins to reduce cord complications.     

Gait patterns in children with hemiplegic spastic cerebral palsy

Our objective was to study uterine and umbilical artery flow resistance during the oxytocin challenge test (OCT). The study population was 21 women with suspected placental insufficiency; one woman was excluded because of a positive OCT with reactive fetal heart rate pattern. We carried out simultaneous electronic fetal heart rate monitoring and Doppler velocimetry of uterine and umbilical artery flow during the OCT. The uterine artery flow resistance increased significantly during contractions in both OCT-positive (n = 5) and OCT-negative (n = 15) cases compared with basal values, but the increase was significantly higher in positive cases. The umbilical artery flow resistance increased significantly during contractions in OCT-positive cases, but was almost unchanged in negative cases. During uterine inactivity, there were no differences between the groups for any vessel. This study showed that fetal heart rate decelerations during the OCT are associated with rapid and exaggerated increases of vascular resistance in both uterine and umbilical arteries. The causal relationship is unknown, but the findings indicate pathophysiological mechanisms revealed only during uterine contractions.     

Premature ventricular systole detection by applanation tonometry

We first identified (and probably stimulated) premature ventricular systoles in six patients while performing Goldmann applanation tonometry. One patient developed atrial fibrillation and one patient had a follow-up electrocardiogram showing increasing numbers of these extra systoles without any other abnormalities. Just as in tonography, these were detected during applanation tonometry as rapid decreases in intraocular pressures followed by a gradual return to prior levels. The decrease in measured intraocular pressure was occasionally 8 mm Hg but usually was between 2 and 5 mm Hg. These systoles probably occurred during the first part of applanation tonometry and during the first few office visits.     

Doppler flow velocity waveforms of the umbilical arteries correlate with intravillous blood volume

OBJECTIVE: My purpose was to measure the volume of the fetoplacental vessel tree and to relate findings to Doppler flow patterns of the umbilical arteries. STUDY DESIGN: One hundred sixty placentas were examined by means of standardized random block placental histomorphometry after delivery and the results were compared with antenatal Doppler findings. RESULTS: There was a high correlation (r = -0.703) between the intravillous blood volume obtained from measurements of intermediate and terminal villi and the Doppler flow velocity waveforms detected within the last week before delivery. Moreover, the reduced size of a vessel tree less than 85 mL is highly predictive of perinatal complications, such as fetal growth restriction, low umbilical artery pH values after birth, reduced Apgar scores, and cesarean section for fetal distress. CONCLUSION: These data suggest that reduced end-diastolic flow velocities in the umbilical arteries are associated with elevated fetoplacental impedance owing to reduced vascularization of intermediate and terminal villi.