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Hans L Hillege - One of the best experts on this subject based on the ideXlab platform.
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associations between cardiovascular parameters and Uteroplacental doppler blood flow patterns during pregnancy in women with congenital heart disease rationale and design of the zwangerschap bij aangeboren hartafwijking zahara ii study
American Heart Journal, 2011Co-Authors: Ali Balci, Krystyna M Sollie, Barbara J M Mulder, Monique W M De Laat, Jolien W Rooshesselink, Arie P J Van Dijk, Elly M C J Wajon, Hubert W Vliegen, Willem Drenthen, Hans L HillegeAbstract:Background Previous research has shown that women with congenital heart disease (CHD) are more susceptible to cardiovascular, obstetric, and offspring events. The causative pathophysiologic mechanisms are incompletely understood. Inadequate Uteroplacental Circulation is an important denominator in adverse obstetric events and offspring outcome. The relation between cardiac function and Uteroplacental perfusion has not been investigated in women with CHD. Moreover, the effects of physiologic changes on pregnancy-related events are unknown. In addition, long-term effects of pregnancy on cardiac function and exercise capacity are scarce. Methods Zwangerschap bij Aangeboren Hartafwijking (ZAHARA) II, a prospective multicenter cohort study, investigates changes in and relations between cardiovascular parameters and Uteroplacental Doppler flow patterns during pregnancy in women with CHD compared to matched healthy controls. The relation between cardiovascular parameters and Uteroplacental Doppler flow patterns and the occurrence of cardiac, obstetric, and offspring events will be investigated. At 20 and 32 weeks of gestation, clinical, neurohumoral, and echocardiographic evaluation and fetal growth together with Doppler flow measurements in fetal and maternal Circulation are performed. Maternal evaluation is repeated 1 year postpartum. Implications By identifying the factors responsible for pregnancy-related events in women with CHD, risk stratification can be refined, which may lead to better pre-pregnancy counseling and eventually improve treatment of these women.
Juliana Gebb - One of the best experts on this subject based on the ideXlab platform.
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first trimester 3d power doppler of the Uteroplacental Circulation space and fetal growth restriction
American Journal of Obstetrics and Gynecology, 2014Co-Authors: Mara Rosner, Peer Dar, Laura Reimers, Thomas Mcandrew, Juliana GebbAbstract:Objective The objective of the study was to compare the 3-dimensional power Doppler (3DPD) of the Uteroplacental Circulation space in the first trimester between women who subsequently deliver growth-restricted vs normally grown neonates. Study Design This was a prospective observational study of singleton pregnancies at 11-14 weeks' gestation. The 3DPD indices, vascularization index, flow index, and vascularization flow index were determined on a Uteroplacental Circulation space sphere biopsy with the virtual organ computer-aided analysis program. Growth restriction was defined as a birthweight less than the 10th percentile for gestational age and was evaluated using both population-based and customized birth curves. Results Five hundred seventy-seven women were enrolled. Five hundred twenty-six were eligible for analysis using population centiles, and 497 were available for evaluation using customized centiles. There was no difference in the first-trimester 3DPD indices between patients with growth-restricted and normally grown neonates using either curve. Conclusion Three-dimensional power Doppler indices of the Uteroplacental Circulation space in the first trimester are similar between neonates who develop growth restriction and those who will grow normally.
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first trimester 3 dimensional power doppler of the Uteroplacental Circulation space a potential screening method for preeclampsia
American Journal of Obstetrics and Gynecology, 2010Co-Authors: Peer Dar, Laura Reimers, Juliana Gebb, Peter S Bernstein, Cynthia Chazotte, Irwin R MerkatzAbstract:Objective The objective of the study was to compare 3-dimensional power Doppler (3DPD) of the Uteroplacental Circulation space (UPCS) in the first trimester between women who develop preeclampsia (PEC) and those who do not and to assess the 3DPD method as a screening tool for PEC. Study Design This was a prospective observational study of singleton pregnancies at 10 weeks 4 days to 13 weeks 6 days. The 3DPD indices, vascularization index (VI), flow index (FI), and vascularization flow index (VFI), were determined on a UPSC sphere biopsy with the virtual organ computer-aided analysis (VOCAL) program. Results Of 277 women enrolled, 24 developed PEC. The 3DPD indices were lower in women who developed PEC. The area under the receiver-operating characteristics curve for the prediction of PEC was 78.9%, 77.6%, and 79.6% for VI, FI, and VFI, respectively. Conclusion Patients who develop PEC have lower 3DPD indices of their UPCS during the first trimester. Our findings suggest that this ultrasonographic tool has the potential to predict the development of PEC.
Eric Jauniaux - One of the best experts on this subject based on the ideXlab platform.
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pathophysiology of placental derived fetal growth restriction
American Journal of Obstetrics and Gynecology, 2018Co-Authors: Graham J Burton, Eric JauniauxAbstract:Placental-related fetal growth restriction arises primarily due to deficient remodeling of the uterine spiral arteries supplying the placenta during early pregnancy. The resultant malperfusion induces cell stress within the placental tissues, leading to selective suppression of protein synthesis and reduced cell proliferation. These effects are compounded in more severe cases by increased infarction and fibrin deposition. Consequently, there is a reduction in villous volume and surface area for maternal-fetal exchange. Extensive dysregulation of imprinted and nonimprinted gene expression occurs, affecting placental transport, endocrine, metabolic, and immune functions. Secondary changes involving dedifferentiation of smooth muscle cells surrounding the fetal arteries within placental stem villi correlate with absent or reversed end-diastolic umbilical artery blood flow, and with a reduction in birthweight. Many of the morphological changes, principally the intraplacental vascular lesions, can be imaged using ultrasound or magnetic resonance imaging scanning, enabling their development and progression to be followed in vivo. The changes are more severe in cases of growth restriction associated with preeclampsia compared to those with growth restriction alone, consistent with the greater degree of maternal vasculopathy reported in the former and more extensive macroscopic placental damage including infarcts, extensive fibrin deposition and microscopic villous developmental defects, atherosis of the spiral arteries, and noninfectious villitis. The higher level of stress may activate proinflammatory and apoptotic pathways within the syncytiotrophoblast, releasing factors that cause the maternal endothelial cell activation that distinguishes between the 2 conditions. Congenital anomalies of the umbilical cord and placental shape are the only placental-related conditions that are not associated with maldevelopment of the Uteroplacental Circulation, and their impact on fetal growth is limited.
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perinatal outcome in pregnancies with a positive serum screening for down s syndrome due to elevated levels of free beta human chorionic gonadotropin
Ultrasound in Obstetrics & Gynecology, 1999Co-Authors: M Palacio, Eric Jauniaux, John Kingdom, E Dell, A Sheldrake, C H RodeckAbstract:OBJECTIVE: To evaluate the potential clinical use of maternal serum free beta-human chorionic gonadotropin (beta-hCG) and uterine artery Doppler investigation to screen for placenta-related adverse outcome in pregnancies at positive risk for Down's syndrome at 15-18 weeks. DESIGN: A cohort of 329 consecutive pregnant women with a singleton viable pregnancy and a positive risk for Down's syndrome was retrospectively investigated. This group was obtained from an unselected population of 3952 women attending the same hospital over a 2-year period. Using the results of this first analysis, we selected a group of 26 women with unexplained high levels of free beta-hCG and followed them prospectively with monthly ultrasound and uterine artery Doppler examinations. RESULTS: In the retrospective cohort, risk ratios stratified for maternal serum beta-hCG multiple of the median (MoM) values indicated that the highest incidence of adverse pregnancy outcome was in those women with values of > or = 5.0. In the prospective study, pregnancy outcome was complicated by Uteroplacental disorders in eight cases. Analysis of the Doppler investigation indicated that, in women with a very high level of hCG, an abnormally high uterine artery pulsatility index (PI) had lower sensitivity and negative predictive value than early diastolic notch, whereas the specificity and positive predictive value were higher for a high uterine artery PI. CONCLUSIONS: These findings suggest an association between a high level of maternal serum beta-hCG at 15-18 weeks, the presence of an early diastolic notch in the uterine artery flow velocity waveform and adverse pregnancy outcome due to abnormal development of the Uteroplacental Circulation. Young women with an unexplained high beta-hCG level would benefit, apart from detailed sonography of the fetus and/or karyotyping, from uterine Doppler investigation and counselling about the follow-up and management of placenta-related pregnancy disorders.
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maternal Circulation in the first trimester human placenta myth or reality
American Journal of Obstetrics and Gynecology, 1997Co-Authors: Richard Jaffe, Eric Jauniaux, J HustinAbstract:The classic theory of development of the Uteroplacental and intervillous Circulation determined that maternal blood enters the intervillous space in high-pressure streams from the early first trimester. This theory has recently been challenged and our hypothesis to be presented is that the intervillous Circulation is not fully established until the end of the first trimester. Ex vivo studies of hysterectomy specimens have demonstrated that trophoblastic plugs obstruct blood flow into the intervillous space in early pregnancy and only at 12 to 13 weeks do these plugs become loose and allow for continuous maternal blood flow into the intervillous space. This concept is supported by many other experimental findings. In complicated early pregnancies the Uteroplacental Circulation demonstrates flow characteristics that are strikingly different from those of normal early pregnancies. In abnormal pregnancies increased flow within the intervillous space is demonstrated by color Doppler imaging. Our hypothesis supports other studies that have shown that the embryo favors an environment low in oxygen during early development and that oxygen levels in placental tissue are low in the early first trimester. The classic drawing of placental Circulations is based on second- and third-trimester studies, and its applicability to the early first trimester should be revisited because we will show that new data support the hypothesis that the development of the early intervillous Circulation is a progressive phenomenon.
Ali Balci - One of the best experts on this subject based on the ideXlab platform.
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associations between cardiovascular parameters and Uteroplacental doppler blood flow patterns during pregnancy in women with congenital heart disease rationale and design of the zwangerschap bij aangeboren hartafwijking zahara ii study
American Heart Journal, 2011Co-Authors: Ali Balci, Krystyna M Sollie, Barbara J M Mulder, Monique W M De Laat, Jolien W Rooshesselink, Arie P J Van Dijk, Elly M C J Wajon, Hubert W Vliegen, Willem Drenthen, Hans L HillegeAbstract:Background Previous research has shown that women with congenital heart disease (CHD) are more susceptible to cardiovascular, obstetric, and offspring events. The causative pathophysiologic mechanisms are incompletely understood. Inadequate Uteroplacental Circulation is an important denominator in adverse obstetric events and offspring outcome. The relation between cardiac function and Uteroplacental perfusion has not been investigated in women with CHD. Moreover, the effects of physiologic changes on pregnancy-related events are unknown. In addition, long-term effects of pregnancy on cardiac function and exercise capacity are scarce. Methods Zwangerschap bij Aangeboren Hartafwijking (ZAHARA) II, a prospective multicenter cohort study, investigates changes in and relations between cardiovascular parameters and Uteroplacental Doppler flow patterns during pregnancy in women with CHD compared to matched healthy controls. The relation between cardiovascular parameters and Uteroplacental Doppler flow patterns and the occurrence of cardiac, obstetric, and offspring events will be investigated. At 20 and 32 weeks of gestation, clinical, neurohumoral, and echocardiographic evaluation and fetal growth together with Doppler flow measurements in fetal and maternal Circulation are performed. Maternal evaluation is repeated 1 year postpartum. Implications By identifying the factors responsible for pregnancy-related events in women with CHD, risk stratification can be refined, which may lead to better pre-pregnancy counseling and eventually improve treatment of these women.
C P Lee - One of the best experts on this subject based on the ideXlab platform.
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pregnancy screening by uterine artery doppler velocimetry which criterion performs best
Obstetrics & Gynecology, 1995Co-Authors: F Y Chan, Tingchung Pun, C Lam, J Khoo, C P LeeAbstract:Objective To test whether repeating Doppler studies of the Uteroplacental Circulation late in gestation will improve the test's power for predicting pregnancy-induced hypertension and fetal growth restriction (FGR), and whether analysis based on a combination of quantitative and qualitative assessments of the uterine arterial waveforms will yield better results than analysis based on either alone. Methods A total of 358 patients considered to be at medium risk for the development of pregnancy-induced hypertension and FGR were recruited. Continuous-wave Doppler studies of the uterine arteries were performed serially at 20, 28, and 36 weeks' gestation. The values of various Doppler indices in the prediction of subsequent pregnancy complications were tested at different gestations and different cutoff levels. The overall significance of performance of the Doppler indices was assessed by the Cohen kappa index, which tests the extent of agreement between the test and the “truth” over that by random chance agreement. Results A total of 974 examination results on 334 patients were available for analysis. We found that Doppler studies of the uterine arteries at 28 and 36 weeks were less useful than studies performed at 20 weeks. Serial studies at 20 and 28 weeks showed only marginal improvement when compared with a single study at 20 weeks. The best criteria were a mean resistance index (RI) of uterine arteries above the 90th percentile and the presence of diastolic notches in both uterine arteries at 20 weeks. Although the overall kappa index only suggested fair to good agreement beyond chance, the positive predictive value for subsequent complications was good: 57% for severe complications and 93% for any complications. Conclusion Doppler studies of the uterine artery as a test for the subsequent development of pregnancy complications are best performed at 20 weeks with a combination of RI measurements and the assessment of the presence of diastolic notches.
