[Fetal cardiac interventions]

Fetal cardiac interventions are being performed with growing success by a minimally invasive percutaneous and transthoracic approach. The primary aim of these interventions is to minimise postnatal morbidity and mortality, rarely also to achieve intrauterine survival. Valvuloplasty in utero for severe aortic stenosis is performed in order to achieve sufficient growth of the left ventricle and to make a later biventricular repair possible. In rare cases with hydrops secondary to massive left ventricular dilatation and mitral insufficiency it is used as a salvage therapy. Premature obstruction of the foramen ovale can be treated by balloon atrioseptoplasty or stenting of the atrial septum with the aim to attain a decompression of the left atrium and consequently of the pulmonary veins. This might reduce the extent of pulmonary hypertension and the resulting vascular and parenchymal changes in affected infants. Intrauterine valvuloplasty of a highly stenotic pulmonary valve or a pulmonary atresia with intact ventricular septum in order to prevent hypoplasia of the right ventricle and to enable postnatal biventricular repair is only rarely justified. Currently these intrauterine cardiac interventions are limited to a small group of fetuses with cardiac defects. However, with enhanced imaging modalities and equipment and with growing experience, fetal cardiac interventions are likely to increase in the next years.

Assessment of fetal global and regional ventricular function in congenital heart disease using a novel feature tracking technique

PURPOSE

The aim of this study was to assess global and regional longitudinal peak systolic ventricular function in fetuses with congenital heart disease (CHD) and compare measurements derived from feature tracking with reference values of healthy fetuses with a matching gestational age.

MATERIALS AND METHODS

Global and segmental longitudinal peak systolic strain (LPSS), strain rate and velocity values of the left (LV) ventricular myocardium and right (RV) ventricular myocardium were assessed by a novel feature tracking technique in 17 fetuses with congenital heart disease (10 fetuses with left heart obstruction (LHO), 5 fetuses with tetralogy of Fallot (TOF) and 2 fetuses with double outlet right ventricle (DORV)) and were compared in a second step with 24 matched healthy fetuses (gestational age range 21 - 36 weeks of gestation).

RESULTS

The global LPSS of both ventricles was slightly elevated in fetuses with TOF or DORV compared with controls (RV: p = 0.055; LV: p = 0.063). The RV strain rate presented a trend toward higher values (p = 0.09). Corresponding global LV velocity values of fetuses with TOF or DORV revealed a tendency to decrease compared to healthy controls (p = 0.054). In contrast, all measurements of fetuses with LHO did not show any statistical difference regarding deformation parameters or velocity compared to healthy controls.

CONCLUSION

Global longitudinal peak systolic measurements in fetuses with congenital heart disease revealed slightly higher strain (RV/LV) and strain rate (RV) values in the subgroup of fetuses with TOF or DORV compared to healthy controls. Whether the application of this new angle-independent technique is suitable for discriminating between healthy and diseased fetuses has to be verified in further investigations.

[Allogeneic stem cell transplantation for acute myeloid leukemia and HIV infection--case 3/2012]

HISTORY AND ADMISSION FINDINGS

A 27-year-old male patient with a past medical history of HIV presented with acute myeloid leukemia for allogeneic hematopoietic stem cell transplantation (HSCT). Highly active anti-retroviral therapy suppressed the viral load below detection threshold.

INVESTIGATIONS

There were no contraindications for allogeneic HSCT.

TREATMENT AND COURSE

Myeloablative conditioning consisted of total body irradiation and cyclophosphamide. Anti-thymocyte globulin, tacrolimus and mycophenolate mofetil were used for immunosuppression. Combined anti-retroviral therapy (nucleoside and nucleotide analog reverse-transcriptase inhibitor, boostered protease inhibitor, maraviroc and raltegravir) was maintained for allogeneic HSCT and viral load remained below detection threshold. No graft-versus-host disease or serious infectious complications occurred. The patient showed good graft function with stable hematopoiesis. Localized Kaposi's sarcoma was diagnosed six months after allogeneic HSCT and treated successfully with surgical excision and reduction of immunosuppression. Almost one year after allogeneic HSCT, the CD4+ cell count is rising and viral load remains below detection threshold with combined anti-retroviral therapy.

CONCLUSION

Allogeneic HSCT can be safely performed in HIV positive patients. Kaposi's sarcoma is a rare event after allogeneic HSCT and linked to strong immunosuppression.

Fetal anemia of unknown cause--a diagnostic challenge

PURPOSE

To assess the spectrum of underlying diseases in cases of fetal anemia in which the cause was unknown at the time of first and second transfusion or thereafter.

MATERIALS AND METHODS

All patients who underwent intrauterine transfusion were identified in the perinatal databases of two tertiary referral centers for prenatal medicine and treatment between 2002 and June 2010.

RESULTS

82 fetuses received intrauterine transfusion in the study period. A total of 356 transfusions were performed in these patients. The causes of fetal anemia in our cohort were alloimmunization (32), parvovirus infection (23), feto-fetal transfusion syndrome (9), sacrococcygeal teratoma (2) and cytomegalovirus infection (1). In the remaining 15 cases, the cause of fetal anemia was unknown at the time of first and second transfusion, and could only be ascertained in the further course of pregnancy, in the postnatal period or was ultimately left in doubt. In all cases markedly elevated peak systolic velocities in the middle cerebral artery accurately predicted fetal anemia. The final diagnosis in these cases was fetomaternal hemorrhage (4), Blackfan-Diamond anemia (1), diffuse neonatal hemangiomatosis with chorangioma (1), kaposi-like hemangioendothelioma (1), elliptocytosis (1), neonatal hemochromatosis (1), mucopolysaccharidosis type VII (1) and in 5 cases the cause of fetal anemia remained unexplained. The latter 5 cases had an uneventful postnatal course and did not require further transfusions in infancy.

CONCLUSION

In cases of fetal anemia with negative indirect Coombs test and TORCH serology, rare causes of anemia have to be considered. Fetal studies should therefore include reticulocyte count, parameters of hemolysis, peripheral blood smear and fetal liver function tests. Maternal studies should involve a search for fetal red cells using flow cytometry rather than Kleihauer-Betke test.

Duration of persistent abnormal ductus venosus flow and its impact on perinatal outcome in fetal growth restriction

OBJECTIVE

To study if the duration of individual Doppler abnormalities is an independent predictor of adverse outcome in fetal growth restriction (FGR) caused by placental dysfunction.

METHODS

This was a secondary analysis of patients with FGR (abdominal circumference < 5(th) percentile and umbilical artery (UA) pulsatility index (PI) elevation) who had at least three examinations before delivery. Days of duration of absent/reversed UA end-diastolic velocity (UA-AREDV), low middle cerebral artery PI (brain sparing), ductus venosus (DV) and umbilical vein Doppler abnormalities were related to stillbirth, major neonatal morbidity and intact survival.

RESULTS

One hundred and seventy-seven study participants underwent a total of 1069 examinations. The duration of an absent/reversed a-wave in the DV (DV-RAV) was significantly higher in stillbirths (median, 6 days) compared with intact survivors and those with major morbidity (median, 0 days for both; P = 0.006 and P = 0.001, respectively). Duration of brain sparing was also longer in stillbirth cases compared with intact survivors (median, 19 days vs. 9 days, P = 0.02). Stepwise multinomial logistic regression showed that gestational age at delivery was a significant codeterminant of outcome for all arterial Doppler abnormalities when the DV a-wave was antegrade. However, when present, the duration of DV-RAV was the only contributor to stillbirth (probability of stillbirth = 1/(1 + exp - (interval to delivery × 1.03 - 2.28)), r2 = 0.73). Receiver-operating characteristics curve statistics showed that a DV-RAV for > 7 days predicted stillbirth (100% sensitivity, 80% specificity, likelihood ratio = 5.0, P < 0.0001). In contrast, neither neonatal death nor neonatal morbidity was predicted by the days of persistent DV-RAV.

CONCLUSIONS

The duration of absent or reversed flow during atrial systole in the DV is a strong predictor of stillbirth that is independent of gestational age. While prematurity remains the strongest predictor of neonatal risks it is unlikely that pregnancy can be prolonged by more than 1 week in this setting.

Reference ranges for Doppler assessment of uterine artery resistance and pulsatility indices in dichorionic twin pregnancies

OBJECTIVES

To construct reference ranges of uterine artery Doppler parameters against gestation in twin pregnancies and to present charts of the pulsatility index (PI) and resistance index (RI) for clinical use.

METHODS

This was an observational study of the uterine circulation in 557 women with dichorionic twin pregnancies at 17-38 weeks' gestation. Uterine artery measurements were performed by color and pulsed Doppler imaging. The uterine artery PI and RI were calculated as a mean of both sides. Reference ranges were constructed by regression of each index on gestational age. For this purpose, a regression model with fractional polynomials was fitted to the data. Furthermore, the presence of uterine artery notching was recorded.

RESULTS

New reference curves and tables of percentiles of the uterine artery PI and RI are presented. The calculated indices both showed a significant decrease with gestational age. Compared with singleton values, mean twin PI values were lower during the whole course of pregnancy. The prevalence of bilateral notching was 4.6% at 17-19 weeks' gestation and 3.1% at 20-24 weeks.

CONCLUSIONS

Uterine artery Doppler indices in twin pregnancies are lower than in singleton pregnancies. Therefore, the use of uterine artery reference ranges adapted to twin gestations seems more appropriate for identifying low- and high-risk groups.

Echocardiography in the fetus--a systematic comparative analysis of standard cardiac views with 2D, 3D reconstructive and 3D real-time echocardiography

PURPOSE

The aim of our study was to assess the feasibility and reliability of fetal three-dimensional reconstructive echocardiography using freehand technique (3DR) and 3D real-time echocardiography using matrix technology (RT-3D) in consecutive series of pregnancies and to compare the findings with the gold standard 2D ultrasound, as well as postnatal findings.

MATERIALS AND METHODS

Fifty consecutive pregnant women (gestational age 19+3 to 37+0) including 10 fetuses with cardiac malformations were scanned prospectively with 2D, 3DR and RT-3D. 3D data sets were evaluated by a blinded independent examiner. The visualization rates for standard cardiac views and structures were determined and the quality and diagnostic accuracy of each modality were calculated.

RESULTS

In RT-3D, the visualization rate of fetal cardiac views was equivalent to 2D, but was significantly lower for 3DR (4cv: 2D 98%, RT-3D 100%, 3DR 96% RVOT: 2D 96%, RT-3D 98%, 3DR 84%). Short-axis views or views of the complete aortic or ductal arch were more readily identified in RT-3D than in 2D (2D 70%, RT-3D 82%). 3DR was more susceptible than RT-3D to artifacts during acquisition and post-processing. The sensitivity and overall accuracy were significantly higher for 2D and RT-3D than for 3DR, when prenatal data was compared with postnatal findings.

CONCLUSION

3D freehand reconstruction has significantly lower visualization rates and overall accuracy compared to 2D and RT-3D. RT-3D echo is a feasible and reliable method for imaging the fetal heart. Offering the opportunity of data post-processing and evaluation, RT-3D is a promising method for improving the accuracy of sonographic analysis of fetal cardiac morphology and function.

Decision making and attitudes towards invasive prenatal diagnosis in the early second trimester

PURPOSE

To investigate the impact of the a priori attitude, nondirective counselling and targeted second trimester ultrasound examination on the decision process concerning invasive prenatal diagnosis in the second trimester.

MATERIAL AND METHODS

A prospective study including 696 high-risk pregnancies at 15 to 18 weeks' gestation, performed from 2005-2007. Attitudes towards invasive prenatal testing were explored before and after genetic counselling and targeted ultrasound examination in a tertiary referral centre.

RESULTS

Initially, 311 (44.7%) women intended to have an invasive testing (group 1), 150 women (21.5%) were against an invasive procedure (group 2), and 235 women (33.8%) wanted to make their final decision depending on the sonographic result (group 3). The total rate of amniocentesis was 87.1%, 5.3% and 13.6%, respectively. Overall, the a priori decision was sparsely influenced by the ultrasound examination. Only 12.9% (40/311) and 5.3% (8/150) of the primarily determined women (group 1, 2) changed their opinion. However, in the initially undecided group, 86.7% declined an amniocentesis after a normal ultrasound scan.

CONCLUSION

The referral indication and the a priori opinion are the strongest influencing factors with regard to invasive testing and the ultrasound scan has a low impact in those preselected patients. However, ultrasound has an important reassuring aspect in women willing to use ultrasound as assistance in the process of decision making.

Nuchal fold thickness, nasal bone absence or hypoplasia, ductus venosus reversed flow and tricuspid valve regurgitation in screening for trisomies 21, 18 and 13 in the early second trimester

OBJECTIVE

To investigate the performance of nuchal fold thickness, nasal bone hypoplasia, reversed flow in the ductus venosus and tricuspid valve regurgitation in the prediction of fetal aneuploidies in the early second trimester.

METHODS

This was a prospective study of 870 fetuses at 14 + 0 to 17 + 6 weeks of gestation, performed from 2005 to 2007. In all cases we assessed classical structural anomalies, second-trimester markers of aneuploidy including nuchal fold thickness and nasal bone length, as well as ductus venosus blood flow pattern and tricuspid valve regurgitation.

RESULTS

The study group included 37 fetuses with trisomy 21, eight with trisomy 18 and four with trisomy 13. Nasal bone hypoplasia was the single most sensitive parameter to identify fetuses with trisomy 21. Independent from maternal age, screening by assessment of nuchal fold and nasal bone identified 64.9% of cases with trisomy 21 and 66.7% of cases with trisomy 18/13 (false-positive rate (FPR), 5.8%). By including ductus venosus and tricuspid flow evaluation, the detection rate increased to 75.7% for trisomy 21 and 83.3% for trisomy 18/13 (FPR, 10.8%). Identification of fetuses with structural abnormalities combined with assessment of all four markers under investigation raised the detection rate of trisomy 21 to 83.9% and that of trisomy 18/13 to 100%. The sensitivity of classical second-trimester markers was 62.2% for trisomy 21 and 70.6% for other autosomal aneuploidies (FPR, 11.3%).

CONCLUSION

The combination of assessment of nuchal fold thickness, nasal bone hypoplasia, ductus venosus reversed flow and tricuspid regurgitation in the early second trimester is associated with a higher detection rate of autosomal trisomies compared with classical second-trimester marker screening.