Significance of chromosome 22q11 analysis after detection of an increased first-trimester nuchal translucency

OBJECTIVE

To determine the value of performing routine fluorescent in situ hybridization (FISH) for microdeletions of chromosome 22q11 when karyotyping fetuses with increased nuchal translucency.

DESIGN

This was a prospective observational study carried out over an 18-month period. Fetal karyotyping by chorionic villus sampling was offered to 5429 women attending for a routine booking scan in the first trimester when their nuchal translucency adjusted risk for Down syndrome was > or = 1 in 300. Cytogenetic samples were routinely tested for the 22q11 microdeletion when the nuchal translucency was > or = 3 mm.

RESULTS

The prevalence of increased nuchal translucency > or = 2.5 mm was 180 (3.3%) and > or = 3.5 mm was 42 (0.8%). None of 75 fetuses with an increased nuchal translucency and normal karyotype demonstrated a 22q11 microdeletion on FISH analysis. In the same cohort, 3 of 20 (15%) cases of major congenital heart defects in which nuchal translucency was measured, had a nuchal translucency measurement > or = 2.5 mm.

CONCLUSIONS

Routine FISH analysis for chromosome 22q11 microdeletions at the time of chorionic villus sampling for increased first-trimester nuchal translucency is of limited value. As a significant proportion of fetuses with increased nuchal translucency will be found to have congenital heart defects later in the pregnancy, FISH analysis for chromosome 22q11 microdeletions can be targeted to fetuses with specific congenital heart defects. Tissue from the chorionic villus sampling should therefore be stored for subsequent analysis, until after detailed echocardiography is performed.

Early prenatal diagnosis of major congenital heart defects

Specialized fetal echocardiography at 18 to 22 weeks for high-risk groups is well established as being sensitive and specific for most cardiac abnormalities. Early fetal echocardiography (< 16(+0) weeks, i.e. 16 weeks and 0 days) is a feasible alternative to mid second trimester scanning for families at risk of congenital heart disease. Two main areas have contributed to the increasing interest in first and early second trimester fetal echo. The recognition of the association between increased nuchal translucency and structural heart abnormalities has led to the identification of an important high-risk group at 11 to 14 weeks. Furthermore, the use of modern ultrasound technology has allowed greater utilization of transabdominal scanning in addition to the transvaginal route. Most major structural heart defects can accurately be diagnosed from the late first trimester of pregnancy and many families at-risk can be reassured of 'normality' of cardiac connections at an early stage. Some lesions may evolve throughout pregnancy and therefore early scans should not replace mid trimester fetal echocardiography.

Prenatal diagnosis of mosaic trisomy 8 in a fetus with normal nuchal translucency thickness and reversed end-diastolic ductus venosus flow

We report a case of the prenatal diagnosis of trisomy 8 in a fetus presenting with normal nuchal translucency of 0.8 mm and reversed end-diastolic ductus venosus blood flow at a routine first-trimester scan at 11 weeks of gestation. No structural abnormalities were detected by the ultrasound scan. Karyotyping by chorionic villus sampling led to the diagnosis of mosaic trisomy 8, which was confirmed by fluorescent in-situ hybridization on fetal tissue samples.

Limitations of using first-trimester nuchal translucency measurement in routine screening for major congenital heart defects

OBJECTIVE

To evaluate the effectiveness of nuchal translucency (NT) measurement in screening for major congenital heart disease (CHD) in chromosomally normal fetuses.

DESIGN

A population based cohort study of all women having fetal NT measurement at 10-14 weeks of gestation in an unselected population over a 3-year period. The outcome measure was the identification of major CHD in chromosomally normal pregnancies either antenatally or postnatally.

RESULTS

Major defects of the heart and great arteries were identified in 26 out of 7339 pregnancies (prevalence 3.5 per 1000 pregnancies). Out of 26 cases, only four (sensitivity 15.4%, 95% CI 4-35) were in the group of 258 pregnancies (3.5%) with increased NT of > or = 2.5 mm. The prevalence of major CHD increased from 3.1 per 1000 for NT < 2.5 mm to 50 per 1000 for NT > or = 3.5 mm (likelihood ratio of 14.1, 95% CI 4.2-47.9). The positive and negative predictive values for NT > or = 2.5 mm were 1.6% and 99.7%, respectively.

CONCLUSIONS

The prevalence of major CHD in this study was 3.5 per 1000, suggesting that ascertainment of CHD in our study population was thorough. Fetuses with NT measurements > or = 3.5 mm have a significantly increased risk of major CHD, and this identifies a subgroup of high-risk patients in whom early fetal echocardiography would be advocated. The low sensitivity of NT for major CHD in the general population, however, indicates that NT cannot be relied on as the sole or major screening tool for this condition as previously reported.

Congenital absence of portal vein in the fetus: a case report

Congenital absence of portal vein (CAPV) is a rare abnormality, which may be associated with other abnormalities. We report a case of prenatal diagnosis of absent portal vein confirmed on postnatal ultrasonography and computed tomography scan. The ultrasound features of CAPV include dilated intra-abdominal segment of umbilical vein, dilated inferior vena cava and the presence of hyperechogenic areas in the liver. Blood coming from the umbilical vein directly drains into the inferior vena cava. The dilated intra-abdominal segment of the umbilical vein shows high velocity pulsatile flow, resembling that of ductus venosus. These findings should prompt a careful search for the portal vein and any associated anomalies.

Screening for fetal aneuploidies and fetal cardiac abnormalities by nuchal translucency thickness measurement at 10-14 weeks of gestation as part of routine antenatal care in an unselected population

OBJECTIVES

To evaluate first trimester pregnancy screening for fetal aneuploidy and congenital heart defects by maternal age and nuchal translucency measurement and screening for fetal aneuploidies and congenital heart defects by ultrasound in an unselected population.

DESIGN

A prospective study.

SETTING

Fetal medicine unit, St George's Hospital, London.

SAMPLE

4523 consecutive viable fetuses at 10-14 weeks with a crown-rump length between 38 and 80 mm were scanned transabdominally (93%) or transvaginally (7%).

METHODS

Screening was performed by calculating the background risk from maternal age, gestational age and obstetric history, which was then adjusted with the nuchal translucency measurement in relation to crown-rump length (adjusted risk).

MAIN OUTCOME MEASURES

Measurements of crown-rump length and nuchal translucency thickness. An adjusted risk of > 1:270 was considered as a positive screening test. Pregnancy outcome was obtained through karyotyping, outcome questionnaires and examination of the newborn infants.

RESULTS

Mean maternal age was 29-4 years and mean gestational age 12.2 weeks. Screening was positive in 230/4523 fetuses (5.1%), when the adjusted risk (mean 1:2649) was > 1:270. Fetal karyotype was abnormal in 23 (0.51%) cases, including twelve with trisomy 21, five trisomy 18, one trisomy 13, one trisomy 10, one monosomy X and two triploidies. For a false positive rate of 4.7%, the sensitivity of this test was 78% in detecting any fetal aneuploidy. Only one out of nine major congenital heart defects in this population was found within the 110 euploid fetuses with increased nuchal translucency thickness (> 2.5 mm).

CONCLUSION

Screening for fetal aneuploidy by maternal age and nuchal translucency measurement can be effective in an unselected population. However, our results do not support its effectiveness in the detection of cardiac abnormalities.

Anomalous origin of the left coronary artery from the pulmonary trunk. Clinical features and midterm results after surgical treatment

OBJECTIVE

To report the authors' experience with the anomalous origin of the left coronary artery (AOLCA) from the pulmonary trunk, emphasizing preoperative data, surgical aspects and midterm results of the follow-up.

METHODS

Retrospective analysis of 11 patients operated upon at the Royal Brompton Hospital from October, 84 to April, 97.

RESULTS

Nine infants had heart failure (HF) and two other children presented with dyspnea and chest pain. All had ECG changes. The echocardio-gram identified the anomalous origin of the coronary artery in 7 (64%) patients and hemodynamic studies were performed in 7 patients. All infants were operated upon between the 2nd and 10th month of life. Six patients were treated with aortic reimplantation of the left coronary artery, whereas five were operated upon according to the Takeuchi technique. All patients are alive, with clear improvement of the ECG changes and ventricular function, as evaluated by echocardiography. Two patients operated upon according to the Takeuchi technique required additional surgery due to severe supravalvular pulmonary stenosis.

CONCLUSION

AOLCA is a rare disease. Most patients show early signs of severe HF associated with ECG findings. Surgical therapy must be instituted early in the disease, preferentially through aortic implantation of the anomalous coronary artery, with a high possibility of success. Shortly after surgery, clinical and ECG improvement, as well as normalization of left ventricular function, should be expected.

Normal relationships between cardiovascular variables in active orthostatism and clinostatism in postural change

OBJECTIVE

Autonomic modulation of hemodynamics, essential for the preservation of homeostasis, is well tested by the abrupt postural change from clinostatism to active orthostatism. The aim of this work was to study normal relationships between the cardiovascular variables in active orthostatism and those in clinostatism.

METHODS

Hemodynamic parameters in clinostatism and orthostatism were easily measured in 20 healthy subjects of both sexes, aged between 33 and 78 years, without treatment, using the non-invasive thoracic electric bioimpedance method.

RESULTS

Cardiovascular variables values in orthostatism are linearly related with their values in clinostatism.

CONCLUSIONS

Results show that cardiovascular variables in active orthostatism are linearly related with their values in clinostatism, each variable being specially regulated. A clinostatism and orthostatism intraindividual correlation was obtained, which provides an easily accessible method of detection and interpretation of autonomic dysfunctions, without deleterious consequences for the subjects, which can be very useful for research on physiopathologic mechanisms.

The cobweb syndrome: first trimester sonographic diagnosis of multiple amniotic bands confirmed by fetoscopy and pathological examination

Amniotic band syndrome is a well described clinical entity presenting with deformities of the limbs, thorax, craniofacial skeleton, soft tissues and umbilical cord, but it still lacks a precise definition and a coherent hypothesis for its pathogenesis. We report on a case of first trimester diagnosis of amniotic band syndrome by sonography and fetoscopy. This revealed multiple abnormalities including facial cleft, brain and limb deformities; the appearance of the amniotic cavity was that of a cobweb containing the fetus. Post-mortem examination and histopathological studies confirmed the diagnosis of amniotic band syndrome. These results may enhance the knowledge of its natural course. In addition, based on histological and newly identified ultrastructural features, we present a hypothesis which could help to explain the aetiopathogenesis of the amniotic band syndrome.

Coronary arterial anatomy in tetralogy of Fallot: morphological and clinical correlations

OBJECTIVE

To clarify the problems in angiographic diagnosis of major coronary arteries crossing the right ventricular outflow tract.

DESIGN

A retrospective study with clinicomorphological correlations to ascertain any aberrant coronary arteries and variations in distribution of the normal right coronary arterial branches.

SETTING

Tertiary referral centre.

SUBJECTS

36 necropsy specimens together with the aortograms and surgical reports from 130 patients with tetralogy of Fallot.

RESULTS

A preventricular branch was found in 19% of cases with tetralogy of Fallot, but in none of 13 normal hearts. Aberrant origin of the anterior interventricular coronary artery was found in 14% of the specimens. The combination of "laid back" and straight lateral views, when reviewed retrospectively, identified this anomaly correctly in nine of 16 patients, with these findings confirmed at surgery in seven patients. A major branch initially thought to cross the outflow tract was shown retrospectively to be an infundibular artery in six, with surgical confirmation in four. It was a preventricular branch in another patient.

CONCLUSIONS

Using the laid back view alone, infundibular and preventricular branches may be mistaken for a major aberrant artery. A combination of laid back and straight lateral views is needed to avoid false positive diagnosis.

First-trimester transabdominal fetal echocardiography

BACKGROUND

Fetal echocardiography is usually done during the second trimester of pregnancy, but waiting until that time can lead to anxiety for the parents if the fetus is at high risk of having cardiac abnormalities. We report the feasibility of transabdominal first-trimester fetal echocardiography for early reassurance of normality or a prenatal diagnosis of a cardiac malformation.

METHODS

We did first-trimester fetal echocardiography and colour-flow mapping with a 5 MHz curvilinear transducer at 13 weeks' gestation (range 12-13+6 days) in 15 fetuses at risk of cardiac defects. The fetus was judged to be normal if the investigation showed normal visceral situs, four-chamber view, and two normally related great arteries of similar size. We did second-trimester scans and neonatal follow-up for the women who continued with their pregnancies; necropsy was done in two cases of pregnancy termination.

FINDINGS

Ten fetuses had normal hearts at the time of the first scan, which was confirmed during second-trimester assessment. In one fetus, the four-chamber view was asymmetrical and a moderate-sized apical muscular ventricular septal defect (VSD) was diagnosed after birth. In another two fetuses we diagnosed small muscular VSD on the second-trimester scans. A complex cardiac malformation was correctly diagnosed in one fetus at 12 weeks of gestation. Thus, in 11 fetuses, the imaging was of sufficient quality to reassure the family or to diagnose an abnormality. In the other four fetuses, the investigation was judged to be incomplete, but no definite cardiac abnormality was identified.

INTERPRETATION

Transabdominal fetal echocardiography in the first trimester of pregnancy is feasible. In most patients the resolution of images is sufficient to allow assessment of basic cardiac anatomy, when normal, or detection of complex malformations, when present.

Dilated endocardial fibroelastosis: unusual late finding with congenital hydrops

The case of a baby born with severe nonimmune hydrops fetalis in whom endocardial fibroelastosis was a late finding is reported. Left ventricular dimensions and systolic function were normal at presentation. After recovery from the hydrops, at 2 months of age, a dilated, poorly contracting left ventricle was documented and eventually led to the infant's death.

Fetal telemedicine: six month pilot of real-time ultrasound and video consultation between the Isle of Wight and London

DESIGN

Prospective audit of first six months.

SETTING

Referral from a district general hospital on the Isle of Wight to a comprehensive tertiary referral service, the Centre for Fetal Care at Queen Charlotte's Hospital 120 km away in London.

PARTICIPANTS

Women whose pregnancy was suspected, or at risk, of fetal abnormality.

INTERVENTIONS

Remote consultation by transmitting ultrasound and video in real-time over ISDN 30 telephone lines. Contemporaneous questionnaire to referring practitioner and patient.

MAIN OUTCOME MEASURES

Frequency, indication, technical success and duration of consultation. Qualitative and semi-quantitative image quality. Effect of teleconsultation on need for physical referral.

RESULTS

Twenty-nine women underwent 39 teleconsultations, and image quality was sufficient for diagnosis in all but one. Fetal abnormalities were present in 76%. Referral in person was required for only four women, significantly fewer than the 13 the referring hospital indicated would have been physically referred in the absence of this service (P < 0.001). Most mothers were counselled by the specialist "face-to-face' over the link, and 80% felt teleconsultation reduced their anxiety.

CONCLUSIONS

A fetal telemedicine service is technically and clinically feasible. This demonstration suggests that such a service reduces the need for physical referral while increasing the rate of consultation, allowing better selection of patients who might benefit from referral. Further evaluation in a variety of clinical settings is now indicated, along with cost-benefit analysis.

Prognostic value of posterior wall thickness in childhood dilated cardiomyopathy and myocarditis

M-mode indices of left ventricular dimension and posterior wall thickness were derived from echocardiograms of children presenting with dilated cardiomyopathy/myocarditis and were related to outcome. Echocardiograms from 16 of 18 children were manually digitized to obtain changes of left ventricular dimension and posterior wall thickness throughout the cardiac cycle. Indices of ventricular function and the ratio of end-diastolic posterior wall thickness to cavity dimensions were obtained. Patients were divided into group I (alive, n = 7), and group II (died, n = 6 or heart transplantation, n = 3) at median follow-up of 25 months. No significant difference was seen for the shortening fraction, the percentage of posterior wall thickening or the normalized peak rate of left ventricular filling. The normalized peak rate of posterior wall thinning was greater in group II. The posterior wall thickness to cavity dimension ratio was higher in group I (median = 0.19) than group II (median = 0.13) (P < 0.005). Five of six survivors, whose ventricular function improved, had ratios > 0.17. All but one with a ratio < or = 0.16 remained with a dilated heart, died or required transplantation (P = < 0.01). A relatively thicker posterior wall (ratio > 0.17) was associated with better prognosis and recovery. This index should be taken into account in decision-making regarding timing for cardiac transplantation.

Recombinant human granulocyte-macrophage colony-stimulating factor reverses neutropenia and reduces secondary infections in visceral leishmaniasis

Twenty-four patients with acute visceral leishmaniasis and leukopenia (< 1500 neutrophils/mm3) due to Leishmania chagasi were studied, 4 in an open-label pilot study and 20 in a double-blind, placebo-controlled trial. Patients received granulocyte-macrophage colony-stimulating factor (GM-CSF), 5 micrograms/kg daily, or placebo for 10 days, plus 10-20 mg/kg pentavalent antimony daily for 20 days. In GM-CSF recipients, neutrophil counts increased threefold and fourfold over baseline at 5 and 10 days, respectively, and were significantly higher than those in placebo recipients (P < .02). Eosinophil and monocyte counts were significantly increase in GM-CSF recipients at 10 days (P < or = .03). Secondary infections occurred in 3 GM-CSF and in 8 placebo recipients (P = .04). All patients had complete resolution of their leishmaniasis at 3 months. Few adverse events were recorded. GM-CSF, 5 micrograms/kg daily for 10 days, was safe, rapidly reversed neutropenia, and reduced the number of secondary infections in patients with leishmaniasis.

Anatomic correction for post-mustard pulmonary venous obstruction

Pulmonary artery banding and arterial switch operation as a two-stage approach have offered a surgical solution to the failing right ventricle after intraatrial repair of the transposition of the great arteries. Banding of the pulmonary artery increases the resistance to the left ventricular output and, therefore, "prepares" the left ventricle for supporting the systemic circulation and arterial switch operation. We report a case of anatomic correction for transposition of the great arteries after intraatrial repair (Mustard's operation) in which the left ventricle was retrained serendipitously as a consequence of pulmonary venous obstruction complicating Mustard's procedure.

Granulocyte-macrophage colony-stimulating factor in combination with pentavalent antimony for the treatment of visceral Leishmaniasis

The efficacy of GM-CSF was investigated in 20 neutropenic patients (< 1500 neutrophils/microliters) with acute visceral leishmaniasis due to Leishmania chagasi. Patients were randomized to receive either GM-CSF, 5 micrograms/kg daily (intravenously or subcutaneously), or placebo for ten days, in combination with pentavalent antimony, 10-20 mg/kg daily for 20 days. Neutrophil counts were significantly greater on days 5 and 10 of treatment in the GM-CSF group compared with the placebo group (p < 0.02). Eosinophil and monocyte counts were also significantly increased in the GM-CSF group at day 10 (p < or = 0.03). Interestingly, at day 30, platelet counts were significantly increased in the GM-CSF group on days 5 and 10 (p = 0.04 and 0.02, respectively). Patients in the GM-CSF group experienced fewer secondary bacterial or viral infections than placebo patients. Infections occurred in only three patients given GM-CSF compared with eight patients given placebo (p < 0.04). All patients had complete resolution of disease symptoms at three months. Few adverse events were recorded. GM-CSF given subcutaneously at a dose of 5 micrograms/kg daily for ten days was well tolerated, reversed neutropenia rapidly and reduced the number of secondary infections in patients with leishmaniasis.