Application of a first-trimester prediction model for pre-eclampsia based on uterine arteries and maternal history in high-risk pregnancies

OBJECTIVE

To assess the value of a prediction model for pre-eclampsia (PE) in the first trimester (Ultrasound Obstet Gynecol 2007;30:742-794) for the prediction of late (>34 weeks) and early (< or =34 weeks) PE in a high-risk population.

METHODS

Longitudinal study performed in 152 high-risk pregnancies with at least one high-risk condition: previous PE, hypertension, pregestational diabetes, renal disease, obesity, hyperlipidemia, autoimmune disorders, thrombophilia or recurrent pregnancy loss. Mean uterine artery pulsatility index at 11 to 13 + 6 weeks and a series of maternal variables were combined in order to obtain the estimated 'a posteriori risk for PE' in each woman. This risk for unaffected women was compared with that for patients who subsequently developed late and early PE. The performance of such approach was described by receiver-operating characteristic curves.

RESULTS

Late PE developed in 13 (8.6%) pregnancies and early PE in seven (4.6%). The median 'a posteriori risk for PE' in the unaffected, late PE, and early PE groups was 0.62%, 1.22%, and 2.49% (P < 0.01), respectively. For a false-positive rate of 10%, the detection rates of late and early PE were 23.1 and 42.9%, respectively.

CONCLUSIONS

This referenced model shows a modest performance when applied to high-risk women.

Placental mesenchymal dysplasia associated with hepatic and pulmonary hamartoma

This report describes a 31-week stillborn female infant with placental mesenchymal dysplasia (PMD) in association with hepatic mesenchymal hamartoma (HMH) and pulmonary hamartoma. Placental mesenchymal dysplasia was initially misdiagnosed as a partial mole. However, histologically, no trophoblastic proliferation or inclusions were observed. Differential diagnosis of the hepatic mass with similar tumors is discussed. To our knowledge, this is the first case of lung hamartoma reported in a fetus and the first case related to PMD and HMH. A common anomalous development of the mesoderm, a reparative post-injury process and a genetic mechanism, have been proposed to explain their pathogenesis.

Prenatal diagnosis of right aortic arch: associated findings, pregnancy outcome, and clinical significance of vascular rings

OBJECTIVES

To analyze the characteristics and clinical implications of right aortic arch (RAA) detected in fetal life.

METHODS

Retrospective study of all cases of RAA diagnosed prenatally in high-risk patients who underwent fetal echocardiography between 2000 and 2007.

RESULTS

There were 48 RAA; 18 had vascular ring (Group 1), including 15 RAA with aberrant left subclavian artery and 3 double aortic arch, and 30 had not vascular ring (Group 2), all RAA with mirror-image branching. The prenatal diagnosis was confirmed in 94%. In Group 1 most fetuses had normal heart (89%), and none had 22q11 deletion. There were 16 live births and all infants but one are asymptomatic (mean follow-up of 31 months). In Group 2 almost all fetuses had congenital heart defects (CHDs) (97%), and five were chromosomally abnormal (17%), including four 22q11 deleted. The 1-year survival rate was 69%, which was significantly higher in Group 1 (89% vs 57%, p < 0.05).

CONCLUSIONS

RAA can be accurately diagnosed by fetal echocardiography. The outlook for these patients largely depends on the presence of associated defects, mainly CHDs, and their severity. If isolated, aortic arch anomalies are asymptomatic vascular variants in most cases. This information is important to assist parental counseling in pregnancy.

Conotruncal anomalies in fetal life: accuracy of diagnosis, associated defects and outcome

OBJECTIVES

To assess the accuracy of prenatal echocardiography, associated anomalies, and outcome of fetuses with conotruncal anomalies (CTA).

STUDY DESIGN

We searched our database for CTA prenatally diagnosed between 1990 and 2005. We included tetralogy of Fallot (TOF), transposition of the great arteries (TGA), double-outlet right ventricle (DORV), truncus arteriosus (TA), pulmonary atresia with ventricular septal defect (PA-VSD) and posterior malalignment type VSD with aortic arch obstruction (pmtVSD-AAO). Data of 144 fetuses with complete follow-up were retrieved and analyzed.

RESULTS

The main reason for referral was suspected heart defect on a routine obstetric scan (72%). Most cases were detected < or =22 weeks (55%). The presence of a CTA was confirmed postnatally in 143 cases (99%), and the diagnosis of the first fetal echocardiography was correct in 126 (87.5%). Most diagnosis of TOF (33/36, 91.7%), TGA (34/38, 89.5%) and DORV (34/38, 89.5%) were proved correct. Inadequate assessment of the interventricular septum, the distal aortic arch and/or the severity of the right outflow tract obstruction accounted for most errors. The accuracy rate was lower in TA (11/14, 78.6%) and PA-VSD (4/7, 57.1%), with evaluation of the branch pulmonary arteries as the main source of discrepancies. In 7/18 incorrect cases subsequent scans allowed to obtain a correct diagnosis. Most fetuses (64%) had an isolated CTA. Thirty-seven had chromosomal anomalies (26%) but none were found in TGA. 22q11 deletion affected 8.7% of the tested patients. Nuchal translucency (NT) was above 95th centile in 19/104 cases (18%) in which NT were measured. Fifty cases were interrupted. The overall one-year survival rate was 71%, with differences between cases with and without associated defects (9/25, 36% vs. 57/68, 83.8%; p<0.01). The uncomplicated forms of TGA and TOF had the best survival rates (100%).

CONCLUSIONS

Most CTA can be diagnosed by fetal echocardiography with a high degree of accuracy. Chromosomal defects should always be ruled out, except for simple TGA. Current survival figures in many isolated CTA, especially simple TGA and TOF, support a change in the "classical" concept that congenital heart defects detected prenatally often have the worst outlook.

CONDENSATION

Most CTA can be diagnosed by fetal echocardiography with a high degree of accuracy. Isolated CTA are more common and most of these may have a favourable outcome.

Role of uterine artery Doppler in interpreting low PAPP-A values in first-trimester screening for Down syndrome in pregnancies at high risk of impaired placentation

OBJECTIVES

Low maternal serum levels of pregnancy-associated plasma protein-A (PAPP-A) are associated with both increased risk of aneuploidies and impaired trophoblastic invasion, while high uterine artery (UtA) resistance is associated with impaired trophoblastic invasion but not with an increased risk of aneuploidies. The aim of this study was to determine whether high UtA resistance plays a role in explaining low PAPP-A levels in the absence of aneuploidies.

METHODS

This was a prospective study of 116 singleton pregnancies at high risk for impaired placentation (having at least one major risk factor: prior history of pre-eclampsia, pregestational diabetes mellitus, chronic hypertension, chronic kidney disease, body mass index >30, autoimmune disorder, thrombophilia or recurrent pregnancy loss), booked for routine assessment of risk for aneuploidies by means of the first-trimester combined screening test (nuchal translucency thickness (NT) + PAPP-A + beta-human chorionic gonadotropin (beta-hCG)). Measurement of NT and the mean UtA pulsatility index (PI) were carried out at the 11 to 13 + 6-week scan. All values were calculated in multiples of the median (MoM) adjusted for gestational age. A cut-off risk of 1/270 at time of sampling was adopted to differentiate high- from low-risk groups for trisomy 21.

RESULTS

There were 108 patients deemed to be at low risk for trisomy 21 and eight at high risk. None had chromosomal defects, giving a false-positive rate for trisomy 21 of 6.9%. The greatest differences between patients at low risk and those at high risk for trisomy 21 were found in their PAPP-A (0.98 vs. 0.38 MoM, P < 0.01) and beta-hCG (1.09 vs. 1.77 MoM, P = 0.04) values. Greater NT thickness (1.02 vs. 0.90 MoM) and higher mean UtA-PI (1.05 vs. 0.96 MoM) were recorded in the high-risk group, although the differences did not reach statistical significance (P = 0.19 and 0.40, respectively). After log-transformation there were no significant correlations between mean UtA-PI and NT and between mean UtA-PI and beta-hCG. There was a significant negative linear correlation between mean UtA-PI and PAPP-A (r = -0.331; P < 0.01). After adjusting the PAPP-A values by UtA-PI, the false-positive rate for trisomy 21 decreased to 2.6%.

CONCLUSION

Mean UtA-PI at the 11 to 13 + 6-week scan may be an effect-modifier variable for PAPP-A that should be taken into account in the first-trimester combined screening for aneuploidies, at least in pregnancies at high risk for impaired placentation.

Hypoplastic left heart syndrome diagnosed in fetal life: associated findings, pregnancy outcome and results of palliative surgery

OBJECTIVES

To analyze the main prenatal characteristics of hypoplastic left heart syndrome (HLHS), its association with extracardiac anomalies including increased nuchal translucency (NT) and the outcome of affected patients.

METHODS

We searched our database for classical forms of HLHS (aortic atresia, mitral and aortic atresia and critical aortic stenosis evolved to a severely hypoplastic left ventricle) prenatally diagnosed between 1998 and 2006. Data on 101 fetuses were retrieved and analyzed.

RESULTS

The main reason for referral was suspected heart defect on a routine ultrasound scan (82%). The mean gestational age at diagnosis was 21 weeks. Most cases were detected at < or = 22 weeks (72%), the upper limit for termination of pregnancy (TOP) in our country (Spain). An intact atrial septum was diagnosed in 11 of the 58 fetuses (19%) in which pulmonary vein blood flow was assessed, and this diagnosis was proved to be correct in the six liveborn babies. Most fetuses (68%) had an isolated HLHS. Fourteen fetuses (14%) were chromosomally abnormal and all had associated extracardiac defects. NT was above the 95th centile in 21 of the 74 cases (28%) in which this measurement was available. 79% (58/73) of the cases in which HLHS was detected at < or = 22 weeks were terminated, and no differences in the rate of TOP were found through the study period. Among the 43 continuing pregnancies, seven fetuses died in utero and there were 36 live births; in 12 cases the parents opted for compassionate care and 24 chose to have the infant surgically treated. In the cohort of intention-to-treat cases, the overall survival rate was 36% (9/25). This rate improved from 18% (2/11) in the period 1998-2002 to 50% (7/14) in 2003-2006. There were no survivors in cases with intact atrial septum or when there were associated defects. At follow-up, 2/9 survivors suffered from significant neurological morbidity.

CONCLUSIONS

Fetal echocardiography allows an accurate diagnosis of HLHS, which is made in most instances in the first half of pregnancy. Despite the advantage offered by the prenatal detection of HLHS, which provides the opportunity to plan perinatal management, our up-to-date results show that the outlook for these fetuses is still poor, and highlight the importance of presenting these figures when counseling parents with affected fetuses.

Neuromuscular control in landing from supra-maximal dropping height

The present study utilized high-impact supra-maximal landings to examine the influence of the pre-impact force level on the post-impact electromyographic (EMG) activity and, in particular, on the short latency EMG reflex (SLR) component. Unilateral-leg landings were performed in a sitting position on a sledge apparatus after release from high, but individually constant dropping height. A lower limb guiding device fixed to the front of the sledge seat allowed the subjects to sustain a given pre-set force level up to impact. This force level was either freely chosen or set at 20, 35, and 50% of maximal isometric plantarflexion force. EMG activity was recorded from eight major lower limb muscles. It was expected that the increase in the pre-impact force level would require the intervention of a protective neural strategy during the post-impact phase that would attenuate the SLR amplitude. The ultrasonography recordings confirmed that the soleus fascicles were stretched to induce SLR. The main finding was the similarity across all tested conditions of the impact peak force and post-impact EMG activity, including the SLR response. Both observations are mostly attributed to the similar EMG levels and close force levels reached toward impact. The instruction to maintain a given pre-set force level was indeed overruled when getting close to impact. It is suggested that, in the present supra-maximal landing condition, a protective central neural strategy did occur that took into account the pre-set force level to secure similar impact loads.

Thermotropic biaxial liquid crystalline phases in a mixture of attractive uniaxial rod and disk particles

We present the first examples of thermotropic biaxial mesophases in mixtures of model attractive uniaxial molecules. Nematic and smectic biaxial phases are identified. The nematic biaxial phase has remained a key challenge in the science of liquid crystals since it was first proposed almost 40 years ago. Very recently the first experimental evidence of stable biaxial nematic phases has been obtained in thermotropic liquid crystals of single component biaxial mesogens. Still elusive is the possibility of stabilizing biaxial nematic phases in mixtures of uniaxial particles. We use Monte Carlo molecular simulations to study model mixtures of rodlike and disklike molecules interacting through two intermolecular potential models: one incorporating spherically symmetric (isotropic) attractive interactions; another with anisotropic attractive interactions. These models exhibit nematic and smectic biaxial phases.

Release hallucinations and visual loss as first manifestations of postoperative unilateral blindness

PURPOSE

Release hallucinations (RH) with insight into the unreality of the hallucination have been reported in association with severe vision loss. Postoperative blindness following nonocular surgery may appear associated with central retinal artery occlusion (CRAO) caused by incorrect head positioning during surgery, intraoperative hypotension, and atherosclerosis. RH may initially mask the loss of vision.

METHODS

Case report.

RESULTS

A 27-year-old woman who had undergone lumbar spinal surgery for right L4-L5 discal herniation developed left eye visual loss and complex visual hallucinations immediately after surgery. Her symptoms were initially considered hallucinations related to the anesthesia and not taken into consideration until 4 days later. Ophthalmic examination disclosed CRAO probably caused by ocular compression during surgery. Optic nerve atrophy appeared during the following 6 years.

CONCLUSIONS

Doctors and auxiliary personnel should be aware that visual hallucinations may be a sign of actual vision damage.

Application of QF-PCR for the prenatal assessment of discordant monozygotic twins for fetal sex

OBJECTIVE

To establish the utility of quantitative fluorescent polymerase chain reaction (QF-PCR) in order to determine the zygosity of multiple pregnancies, as well as to define the origin of the most frequent aneuploidies in amniotic fluid samples.

METHODS

We describe the case of a monochorionic (MC) diamniotic (DA) pregnancy with phenotypically discordant twins (nuchal cystic hygroma and non-immune hydrops in twin A and no anomalies in twin B). QF-PCR was performed for rapid prenatal diagnosis in uncultured amniocytes and subsequently in cultured cells. Polymorphic markers for chromosomes X, Y, 13, 18 and 21 were used for determination of zygosity as well as sex chromosome aneuploidy.

RESULTS

Twin A showed a Turner Syndrome (TS) mosaicism pattern by QF-PCR in uncultured amniocytes. The monozygotic origin of the pregnancy was determined. Interphase fluorescence in situ hybridization (I-FISH) in this sample showed a mosaicism X0/XY (83/17%). Cytogenetic analysis revealed a 45,X0 karyotype in twin A and a 46,XY karyotype in twin B.

CONCLUSIONS

QF-PCR is a reliable tool for the determination of the zygosity independently of the chorionicity and the fetal sex in case of twin pregnancy. Testing both direct and cultured cells can provide useful results for genetic counselling in chromosomal mosaicisms.