Current and potential impact of fetal diagnosis on prevalence and spectrum of serious congenital heart disease at term in the UK. British Paediatric Cardiac Association

Fetal cardiac screening and variation in prenatal detection rates of congenital heart disease: why bother with screening at all?

Antenatal screening for fetal cardiac abnormalities was introduced over 25 years ago, yet detection of congenital heart disease before birth remains a challenge. While experienced tertiary centers report a high level of diagnostic accuracy, with most major forms of congenital heart disease being detectable before birth, the overall detection rate remains low. Pregnancies at increased risk of having an affected baby are referred to tertiary centers for fetal ECG, but most cases of congenital heart disease will occur in low-risk pregnancies. These cases will only be detected by screening the low-risk population at the time of routine obstetric scanning. Many obstetric ultrasound units have learnt to successfully obtain, and correctly interpret, views of the heart, including the four-chamber view and outflow tract views. However, standards for doing this are not uniform, nationally or internationally, so there is a significant variation in detection rates across individual countries and between different countries. Early diagnosis of babies with lesions that can result in cardiovascular collapse and death, could improve their survival as well as reducing morbidity. In addition, detection of a cardiac abnormality during pregnancy allows time to prepare parents for the likely course of events after birth. It also facilitates detection of other abnormalities in the baby and gives parents a choice, even if the choice is difficult and unwelcome. As well as providing parents with accurate and up-to-date information regarding the their baby’s abnormality, it is vital to provide continuing support to help them deal with the problem, regardless of what decisions they make. Much work remains to establish a uniform standard for antenatal detection of cardiac abnormalities. More recent national guidelines for examining the fetal heart along with formalized auditing processes should help to achieve this, although considerable time and effort will be required, particularly with regard to the teaching and training required.

Mortality in infants with cardiovascular malformations

Cardiovascular malformations are an important cause of infant death and the major cause of death due to malformation. Our aims were to analyse and categorise all deaths in infants with cardiovascular malformations, and to analyse trends in mortality over time and influences on mortality. We obtained details of infant deaths and cardiovascular malformations from the population of one health region for 1987-2006. We categorised deaths by cause and by presence of additional chromosomal or genetic abnormalities or non-cardiac malformations. In 676,927 live births the total infant mortality was 4,402 (6.5 per 1,000). A total of 4,437 infants had cardiovascular malformations (6.6 per 1000) of whom 458 (10.3%) died before 1 year of age. Of this number, 151 (33%) deaths had non-cardiac causes, 128 (28%) were cardiac without surgery and 179 (39%) occurred from cardiac causes after surgery. Death was unrelated to the cardiovascular malformation in 57% of infants with an additional chromosomal or genetic abnormality, in 76% of infants with a major non-cardiac malformation and in 16% of infants with an isolated cardiovascular malformation. Terminations of pregnancies affected by cardiovascular malformations increased from 20 per 100,000 registered births in the first 5 years to 78 per 100,000 in the last 5 years. A total of 2,067 infants (47%) underwent surgery and of these 216 (10%) died before 1 year of age.

CONCLUSIONS

A total of 10.4% of infants who died had a cardiovascular malformation and two-thirds of deaths were due to the malformation or its treatment. Mortality declined due to increasing termination of pregnancy and improved survival after operation.

Costs of prenatal detection of congenital heart disease

Little information is available about the transportation costs incurred from the missed prenatal diagnosis of congenital heart disease (CHD). The objectives of the present study were to analyze the costs of emergency transportation related to the postnatal diagnosis of major CHD and to perform a cost/benefit analysis of additional training for ultrasound technicians to study the implications of improved prenatal detection rates. The 1-year costs incurred for emergency transportation of pre- and postnatally diagnosed infants with CHD in Northern California and North Western Nevada were calculated and compared. The prenatal detection rate in our cohort (n = 147) was 30.6%. Infants postnatally diagnosed were 16.5 times more likely (p <0.001) to require emergency transport. The associated emergency transportation costs were US$542,143 in total for all patients with CHD. The mean cost per patient was $389.00 versus $5,143.51 for prenatally and postnatally diagnosed infants, respectively (p <0.001). Assuming an improvement in detection rates after 1-day training for ultrasound technicians, the investment in training cost can be recouped in 1 year if the detection rate increased by 2.4% to 33%. Savings of $6,543,476 would occur within 5 years if the detection rate increased to 50%. In conclusion, CHD diagnosed postnatally results in greater costs related to emergency transportation of ill infants. Improving the prenatal detection rates through improved ultrasound technician training could result in considerable cost savings.

The antenatal detection rate of major congenital heart disease in Scotland

Ultrasonography has been used to detect fetal congenital heart disease since the 1980s, although there has been little uniformity in policy. In the UK, data published for 1993-1995 found an average detection rate of 23.4% with a Scottish rate of 9.6%. At the time of this study, 10 out of the 14 health boards in Scotland were implementing the 16-22-week fetal anomaly scan (FAS). The aims of this study were to determine the rate of antenatal diagnosis of major congenital heart disease (MCHD) throughout Scotland during 1 January to 31 December 2006, to document the regional differences in detection and to determine if implementation of a FAS significantly improved rates. Retrospective data were collected from the centralized Paediatric Cardiac Services in Edinburgh and Glasgow. The database contains information on all infants with cardiac disease in Scotland. All infants requiring cardiac intervention or dying in the first year of life were included. The results showed that the antenatal diagnosis rate for Scotland was 28% (95% CI 21.2%, 34.9%). The Scottish health boards that had implemented the FAS had a significantly higher antenatal detection rate (χ2 test P = 0.037). In conclusion, antenatal detection rate of MCHD varies widely throughout Scotland. Implementation of the FAS has made a significant difference to antenatal diagnosis

Pulse oximetry screening for congenital heart defects in newborn infants (PulseOx): a test accuracy study

BACKGROUND

Screening for congenital heart defects relies on antenatal ultrasonography and postnatal clinical examination; however, life-threatening defects often are not detected. We prospectively assessed the accuracy of pulse oximetry as a screening test for congenital heart defects.

METHODS

In six maternity units in the UK, asymptomatic newborn babies (gestation >34 weeks) were screened with pulse oximetry before discharge. Infants who did not achieve predetermined oxygen saturation thresholds underwent echocardiography. All other infants were followed up to 12 months of age by use of regional and national registries and clinical follow-up. The main outcome was the sensitivity and specificity of pulse oximetry for detection of critical congenital heart defects (causing death or requiring invasive intervention before 28 days) or major congenital heart disease (causing death or requiring invasive intervention within 12 months of age).

FINDINGS

20,055 newborn babies were screened and 53 had major congenital heart disease (24 critical), a prevalence of 2·6 per 1000 livebirths. Analyses were done on all babies for whom a pulse oximetry reading was obtained. Sensitivity of pulse oximetry was 75·00% (95% CI 53·29-90·23) for critical cases and 49·06% (35·06-63·16) for all major congenital heart defects. In 35 cases, congenital heart defects were already suspected after antenatal ultrasonography, and exclusion of these reduced the sensitivity to 58·33% (27·67-84·83) for critical cases and 28·57% (14·64-46·30) for all cases of major congenital heart defects. False-positive results were noted for 169 (0·8%) babies (specificity 99·16%, 99·02-99·28), of which six cases were significant, but not major, congenital heart defects, and 40 were other illnesses that required urgent medical intervention.

INTERPRETATION

Pulse oximetry is a safe, feasible test that adds value to existing screening. It identifies cases of critical congenital heart defects that go undetected with antenatal ultrasonography. The early detection of other diseases is an additional advantage.

FUNDING

National Institute for Health Research Health Technology Assessment programme.

Impact of fetal echocardiography

Prenatal diagnosis of congenital heart disease is now well established for a wide range of cardiac anomalies. Diagnosis of congenital heart disease during fetal life not only identifies the cardiac lesion but may also lead to detection of associated abnormalities. This information allows a detailed discussion of the prognosis with parents. For continuing pregnancies, appropriate preparation can be made to optimize the postnatal outcome. Reduced morbidity and mortality, following antenatal diagnosis, has been reported for coarctation of the aorta, hypoplastic left heart syndrome, and transposition of the great arteries. With regard to screening policy, most affected fetuses are in the “low risk” population, emphasizing the importance of appropriate training for those who undertake such obstetric anomaly scans. As a minimum, the four chamber view of the fetal heart should be incorporated into midtrimester anomaly scans, and where feasible, views of the outflow tracts should also be included, to increase the diagnostic yield. Newer screening techniques, such as measurement of nuchal translucency, may contribute to identification of fetuses at high risk for congenital heart disease and prompt referral for detailed cardiac assessment.

Congenital heart defects and major structural noncardiac anomalies, Atlanta, Georgia, 1968 to 2005

OBJECTIVE

To identify the proportion of major structural noncardiac anomalies identified with congenital heart defects (CHDs).

STUDY DESIGN

Records of infants with CHDs in the Metropolitan Atlanta Congenital Defects Program who were born during the period 1968 through 2005 were classified as having isolated, syndromic, multiple CHD (ie, having an unrecognized pattern of multiple congenital anomalies or a recognized pattern of multiple congenital anomalies of unknown etiology), or laterality defects. Frequencies of associated noncardiac anomalies were obtained.

RESULTS

We identified 7984 live-born and stillborn infants and fetuses with CHDs. Among them, 5695 (71.3%) had isolated, 1080 (13.5%) had multiple, 1048 (13.1%) had syndromic, and 161 (2.0%) had laterality defects. The percentage of multiple congenital anomalies was highest for case with atrial septal defects (18.5%), cardiac looping defects (17.2%), and conotruncal defects (16.0%), and cases with atrioventricular septal defects represented the highest percentages of those with syndromic CHDs (66.7%).

CONCLUSIONS

Including those with syndromes and laterality defects, 28.7% of case infants with CHDs had associated major noncardiac malformations. Thus, infants with CHDs warrant careful examination for the presence of noncardiac anomalies.

Impact and issues of detecting fetal congenital heart defects in Kyushu, Japan

AIM

To determine the current status of fetal CHD screening in our region and to establish a CHD screening system in Japan.

MATERIAL AND METHODS

Subjects were 168 fetuses prenatally-diagnosed with CHD at four referral centers in Japan from 2003 to 2007. Subjects were divided into two groups: group A (n = 84) included cases without extracardiac sonographic abnormalities and known risk factors for CHD and group B (n = 84) included those with extracardiac sonographic abnormalities or risk factors. The diagnostics and outcomes between the groups were analyzed.

RESULTS

There were more cases of single ventricle and restrictive ductus arteriosus and fewer cases of ventricular septal defect and double outlet right ventricle in group A than in group B (P < 0.05). In group A, the most frequent referral reason was an abnormal four-chamber view. In group B, 37 cases had chromosomal anomalies. The mortality rates in group B were higher than those in group A (P < 0.05). There were no differences in mortality rates between fetuses without chromosomal anomalies in group B and group A.

CONCLUSION

Prenatally-diagnosed CHD were mostly limited to those cases with obvious abnormalities in the four-chamber view or those with chromosomal anomalies. Prenatal detection of CHD is useful for the prediction of outcomes.

Turning the pyramid of prenatal care

The current approach to prenatal care, which involves visits at 16, 24, 28, 30, 32, 34 and 36 weeks and then weekly until delivery, was established 80 years ago. The high concentration of visits in the third trimester implies, firstly, that most complications occur at this late stage of pregnancy and, secondly, that most adverse outcomes are unpredictable during the first or even second trimester. This review presents evidence that many pregnancy complications can now be predicted at an integrated first hospital visit at 11-13 weeks by combining data from maternal characteristics and history with findings of biophysical and biochemical tests. It is therefore proposed that the traditional pyramid of care should be inverted with the main emphasis placed in the first rather than third trimester of pregnancy.

The changing epidemiology of congenital heart disease

Congenital heart disease is the most common congenital disorder in newborns. Advances in cardiovascular medicine and surgery have enabled most patients to reach adulthood. Unfortunately, prolonged survival has been achieved at a cost, as many patients suffer late complications, of which heart failure and arrhythmias are the most prominent. Accordingly, these patients need frequent follow-up by physicians with specific knowledge in the field of congenital heart disease. However, planning of care for this population is difficult, because the number of patients currently living with congenital heart disease is difficult to measure. Birth prevalence estimates vary widely according to different studies, and survival rates have not been well recorded. Consequently, the prevalence of congenital heart disease is unclear, with estimates exceeding the number of patients currently seen in cardiology clinics. New developments continue to influence the size of the population of patients with congenital heart disease. Prenatal screening has led to increased rates of termination of pregnancy. Improved management of complications has changed the time and mode of death caused by congenital heart disease. Several genetic and environmental factors have been shown to be involved in the etiology of congenital heart disease, although this knowledge has not yet led to the implementation of preventative measures. In this Review, we give an overview of the etiology, birth prevalence, current prevalence, mortality, and complications of congenital heart disease.

Impact of a regional training program in fetal echocardiography for sonographers on the antenatal detection of major congenital heart disease

OBJECTIVES

The aims of this study were to ascertain the effect of a regional training program in fetal echocardiography for obstetric radiographers on the antenatal detection of major congenital heart disease (CHD) and to document short-term outcomes for major CHD.

METHODS

All 87 obstetric radiographers in Northern Ireland were invited to attend 2.5 days of training during a 1-year period. Data were collected before and after the training, over a 5-year study period, to assess the effect of training on the antenatal detection of CHD in the population.

RESULTS

The antenatal detection of major CHD rose significantly, from 28% (72/262) pretraining to 43% (36/84) in the year of training (P = 0.008). Antenatal diagnosis of four-chamber-view defects rose significantly (from 38% to 54%; P = 0.04), as did detection of outflow-tract-view defects (from 8% to 21%; P = 0.05). Twelve per cent (13/108) of cases died spontaneously in utero and 8% (9/108) were terminated. Only 78% (67/86) of live-born cases in which CHD had been diagnosed antenatally survived the neonatal period, compared to 93% (221/238) with a postnatal diagnosis of CHD (P < 0.001).

CONCLUSIONS

Even with a relatively simple training program, significant improvements can be made in the antenatal detection of CHD. With training, obstetric sonographers can successfully assess outflow tracts. Antenatally diagnosed cases have more complex CHD and this probably contributes to poor neonatal survival.

The 18+0–20+6 Weeks Fetal Anomaly Scan National Standards

Ultrasound screening for fetal abnormalities has been available to pregnant women in England for well over two decades. Historically, clinical departments have used guidance provided by the Royal College of Obstetricians and Gynaecologists to inform them as to what should be included for assessment during the examination. Recently, the Department of Health commissioned the Fetal Anomaly Screening Programme to develop and extend the second trimester anomaly scan to ensure an effective and accessible service for all pregnant women in England. The Fetal Anomaly Scan National Standards have now been launched and will impact on all departments providing this service. This paper summarizes the background to this work, identifies the subtle shift of focus required in the new anomaly scan and explains the rationale behind these changes.

Satisfactory visualization rates of standard cardiac views at 18 to 22 weeks' gestation using spatiotemporal image correlation

OBJECTIVE

The purpose of this study was to determine the frequency with which 3 standard screening views of the fetal heart (4-chamber, left ventricular outflow tract [LVOT], and right ventricular outflow tract [RVOT]) can be obtained satisfactorily with the spatiotemporal image correlation (STIC) technique.

METHODS

A prospective study of 111 patients undergoing anatomic surveys at 18 to 22 weeks was performed. Two ultrasound machines with fetal cardiac settings were used. The best volume set that could be obtained from each patient during a 45-minute examination was graded by 2 sonologists with regard to whether the 4-chamber, LVOT, and RVOT images were satisfactory for screening.

RESULTS

All 3 views were judged satisfactory for screening in most patients: 1 sonologist graded the views as satisfactory in 70% of the patients, whereas the other found the views to be satisfactory in 83%. The position of the placenta did not alter the probability of achieving a satisfactory view, but a fetus in the spine anterior position was associated with a significantly lower probability that the views were regarded as satisfactory for screening (odds ratio, 0.28; 95% confidence interval, 0.09-0.70; P < .05).

CONCLUSIONS

This study suggests that STIC may assist with screening for cardiac anomalies at 18 to 22 weeks' gestation.

The nuchal translucency and the fetal heart: a literature review

In this overview the current knowledge of the relationship between an increased nuchal translucency (NT) measurement and fetal heart structure and function in chromosomally normal fetuses is reviewed. Relevant pathophysiological theories behind the increased NT are discussed. Fetuses with an increased NT have an increased risk for congenital heart disease (CHD) with no particular bias for one form of CHD over another. This risk increases with increasing NT measurement. Although the NT measurement is only a modestly effective screening tool for all CHD when used alone, it may indeed be effective in identifying specific CHD "likely to benefit" from prenatal diagnosis. The combination of an increased NT, tricuspid regurgitation and an abnormal ductus venosus (DV) Doppler flow profile, is a strong marker for CHD. A fetal echocardiogram should be performed at 20 weeks' gestation in fetuses with an NT > or = 95th percentile but < 99th percentile. When the NT measurement is > or = 99th percentile, or when tricuspid regurgitation and/or an abnormal DV flow pattern is found along with the increased NT, an earlier echocardiogram is indicated, followed by a repeat scan at around 20 weeks' gestation. The resultant increased demand for early fetal echocardiography and sonographers with this special expertise needs to be planned and provided for.

Hypoplastic left heart syndrome

Hypoplastic left heart syndrome is a rare congenital heart defect in which the left side of the heart is underdeveloped. Surgical management of hypoplastic left heart syndrome has changed the prognosis of the condition that was previously regarded as fatal. We discuss surgical strategies based on staged procedures, with the right ventricle supporting both systemic and pulmonary circulation. We also discuss other management options, such as neonatal transplantation and the recent innovation of hybrid techniques. Surgical techniques and the understanding of the pathophysiology of this condition have been at the forefront of neonatal cardiac surgery and intensive care. The management of the syndrome remains a challenge because affected children grow into adolescence and adulthood posing various new problems and demands.

Prenatal detection of congenital heart disease

OBJECTIVES

To define current frequency of prenatal detection of congenital heart disease (CHD), factors affecting prenatal detection, and its influence on postnatal course.

STUDY DESIGN

We prospectively identified all fetuses and infants < or =6 months of age with major CHD at 3 referral centers in Northern California over 1 year; we obtained prenatal and demographic data, reviewed prenatal ultrasound (US) and postnatal records, and used logistic regression to analyze maternal, fetal, and prenatal-care provider risk factors for prenatal diagnosis.

RESULTS

Ninety-eight of 309 infants with major CHD had prenatal diagnosis (36% accounting for 27 pregnancy terminations); 185 infant-families participated in the postnatal survey, and although 99% had prenatal US, only 28% were prenatally diagnosed. Anomalous pulmonary venous return (0%), transposition of the great arteries (19%), and left obstructive lesions (23%) had the lowest prenatal detection. Heterotaxy (82%), single ventricle (64%), and HLHS (61%) had the highest. Prenatal diagnosis was higher at university versus community practices (P = .001). Sociodemographics were not associated with prenatal diagnosis. Infants diagnosed prenatally were less frequently ventilated (P < .01) or treated with prostaglandin (P < .05).

CONCLUSIONS

Prenatal detection of major CHD significantly alters postnatal course but remains low despite nearly universal US. CHD type and US practice type are important determinants of prenatal detection.

Prenatal sonographic appearance of truncus arteriosus on wide-band Doppler imaging

Persistent truncus arteriosus is an uncommon congenital cardiac anomaly. In most patients, this condition is not diagnosed prior to birth. We report a case in which this uncommon cardiac anomaly was diagnosed prenatally using wide-band Doppler imaging. When diagnosing fetal truncus arteriosus, sonologists should carefully search for the origin of the main pulmonary artery and for its 2 branches. Our experience suggests that wide-band Doppler imaging facilitates the prenatal diagnosis of truncus arteriosus.

Quality of 2- and 3-dimensional fast acquisition fetal cardiac imaging at 18 to 22 weeks: ramifications for screening

OBJECTIVE

The purpose of this study was to evaluate the frequency with which 6 different fetal cardiac views taken during a fetal ultrasound examination at 18 to 22 weeks' gestation can be obtained satisfactorily for cardiac anomaly screening using either a 2-dimensional (2D) static or 3-dimensional (3D) fast acquisition technique.

METHODS

A prospective study of 100 low-risk women undergoing an anatomic survey was performed. Standard static 2D and 3D fast acquisition volumes were obtained on all patients. The 2D and 3D images were assigned, in a random order, to be independently graded by 3 reviewers. The degree of inter-reviewer agreement was assessed through the use of the Cohen kappa statistic. The factors contributing to satisfactory imaging were evaluated by random effects logistic regression.

RESULTS

A significant proportion of both 2D and 3D images were judged unsatisfactory for screening purposes. However, 2D images were significantly more likely, for all cardiac views, to be judged satisfactory (P < .05). The odds ratios for the 2D technique's being more likely than the 3D technique to provide images satisfactory for screening were 2.6 for the 4-chamber view, 2.4 for the right ventricular outflow tract, 4 for the left ventricular outflow tract, 3.2 for the 3-vessel view, 8.6 for the aortic arch, and 2.2 for the ductal arch.

CONCLUSIONS

In this prospective study, static 2D imaging was significantly more likely than fast acquisition 2D imaging to yield cardiac views of high enough quality to satisfactorily screen for anomalies.

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.

Impact of audit of routine second-trimester cardiac images using a novel image-scoring method

OBJECTIVE

To assess the impact of using an objective scoring method to audit cardiac images obtained as part of the routine 21-23-week anomaly scan.

METHODS

A prospective audit and re-audit (6 months later) were conducted on cardiac images obtained by sonographers during the routine anomaly scan. A new image-scoring method was devised based on expected features in the four-chamber and outflow tract views. For each patient, scores were awarded for documentation and quality of individual views. These were called 'Documentation Scores' and 'View Scores' and were added to give a 'Patient Score' which represented the quality of screening provided by the sonographer for that particular patient (maximum score, 15). In order to assess the overall performance of sonographers, an 'Audit Score' was calculated for each by averaging his or her Patient Scores. In addition, to assess each sonographer's performance in relation to particular aspects of the various views, each was given their own 'Sonographer View Scores', derived from image documentation and details of four-chamber view (magnification, valve offset and septum) and left and right outflow tract views. All images were scored by two reviewers, jointly in the primary audit and independently in the re-audit. The scores from primary and re-audit were compared to assess the impact of feedback from the primary audit.

RESULTS

Eight sonographers participated in the study. The median Audit Score increased significantly (P < 0.01), from 10.8 (range, 9.8-12.4) in the primary audit to 12.4 (range, 10.4-13.6) in the re-audit. Scores allocated by the two reviewers in the re-audit were not significantly different (P = 0.08).

CONCLUSION

Objective scoring of fetal heart images is feasible and has a positive impact on the quality of cardiac images acquired at the time of the routine anomaly scan. This audit tool has the potential to be applied in every obstetric scanning unit and may improve the effectiveness of screening for congenital heart defects.

Prenatal diagnosis and treatment planning of congenital heart defects-possibilities and limits

BACKGROUND

Newborns with hypoplastic left heart syndrome (HLHS) or right heart syndrome or other malformations with a single ventricle physiology and associated hypoplasia of the great arteries continue to be a challenge in terms of survival. The vast majority of these forms of congenital heart defects relate to abnormal morphogenesis during early intrauterine development and can be diagnosed accurately by fetal echocardiography. Early knowledge of these conditions not only permits a better understanding of the progression of these malformations but encourages some researchers to explore new minimally invasive therapeutic options with a view to early pre- and postnatal cardiac palliation.

DATA SOURCES

PubMed database was searched with terms of "congenital heart defects", "fetal echocardiography" and "neonatal cardiac surgery".

RESULTS

At present, early prenatal detection has been applied for monitoring pregnancy to avoid intrauterine cardiac decompensation. In principle, the majority of congenital heart defects can be diagnosed by prenatal echocardiography and the detection rate is 85%-95% at tertiary perinatal centers. The majority, particularly of complex congenital lesions, show a steadily progressive course including subsequent secondary phenomena such as arrhythmias or myocardial insufficiency. So prenatal treatment of an abnormal fetus is an area of perinatal medicine that is undergoing a very dynamic development. Early postnatal treatment is established for some time, and prenatal intervention or palliation is at its best experimental stage in individual cases.

CONCLUSION

The upcoming expansion of fetal cardiac intervention to ameliorate critically progressive fetal lesions intensifies the need to address issues about the adequacy of technological assessment and patient selection as well as the morbidity of those who undergo these procedures.

Cost implications of introducing a telecardiology service to support fetal ultrasound screening

A district hospital in south-east England used a telecardiology service for fetal cardiac diagnosis alongside an existing arrangement for referring pregnant women directly to perinatal cardiologists in London for detailed fetal echocardiography. Women were identified for referral according to local protocols when having a second trimester anomaly scan. For the telemedicine referrals, the sonographers video-recorded images from the anomaly scans for transmission during monthly videoconferences. The cost of the women's antenatal care was calculated from the specialist assessment until delivery, while family costs were collected in a postal survey. Over 15 months, telemedicine was used in 52 cases, while 24 women were seen in London. The London women were more likely to have had an ultrasound abnormality (29% v 10%, P = 0.047). A telemedicine assessment of 5 min duration was more costly than an examination in London (mean cost per referral of £206 v £74, P < 0.001). However, the telecardiology service was cost neutral after 14 days and for the extended period until delivery. Travel costs for London women averaged £37 compared with £5.50 for the telemedicine referrals. Telemedicine may be useful to support perinatal cardiologists in the UK whose workloads are expanding in response to improved standards in antenatal ultrasound screening.

Prevalence of congenital heart defects in metropolitan Atlanta, 1998-2005

OBJECTIVE

To determine an accurate estimate of the prevalence of congenital heart defects (CHD) using current standard diagnostic modalities.

STUDY DESIGN

We obtained data on infants with CHD delivered during 1998 to 2005 identified by the Metropolitan Atlanta Congenital Defects Program, an active, population-based, birth defects surveillance system. Physiologic shunts in infancy and shunts associated with prematurity were excluded. Selected infant and maternal characteristics of the cases were compared with those of the overall birth cohort.

RESULTS

From 1998 to 2005 there were 398 140 births, of which 3240 infants had CHD, for an overall prevalence of 81.4/10 000 births. The most common CHD were muscular ventricular septal defect, perimembranous ventricular septal defect, and secundum atrial septal defect, with prevalence of 27.5, 10.6, and 10.3/10 000 births, respectively. The prevalence of tetralogy of Fallot, the most common cyanotic CHD, was twice that of transposition of the great arteries (4.7 vs 2.3/10 000 births). Many common CHD were associated with older maternal age and multiple-gestation pregnancy; several were found to vary by sex.

CONCLUSIONS

This study, using a standardized cardiac nomenclature and classification, provides current prevalence estimates of the various CHD subtypes. These estimates can be used to assess variations in prevalence across populations, time, or space.

Changing spectrum and outcome of 705 fetal congenital heart disease cases: 12 years, experience in a third-level center

INTRODUCTION

Congenital heart diseases are the most common prenatal and postnatal malformations. Nowadays, fetal echocardiography is a widely practiced technique; however, the impact of prenatal diagnosis on prognosis of the newborns affected by congenital heart disease remains uncertain.

OBJECTIVE

To assess the outcome and the changes in the spectrum of prenatally detected congenital heart disease in our tertiary care centre in 12 years of activity (1995-2006).

METHODS AND RESULTS

We detected 705 congenital heart diseases: 32% (223) were associated with extracardiac or chromosomal anomalies or both, and 68% (482) were isolated. Termination of pregnancy was chosen in 81% for associated anomalies and 37% for isolated anomalies (P<0.001). Of these, more than one-third occurred in hypoplasic left heart cases. The general survival rate was 72%; it was significantly lower in the group with associated heart diseases (46 vs. 80%, P<0.001). Over 12 years we noticed a reduction in the number of multimalformed fetuses and of the hypoplasic left heart cases, and a higher number of aortic arch anomalies detected. During the past 6 years of activity the survival rate obtained has significantly increased (55 to 84%, P<0.05), the termination rate has significantly decreased (35 to 14%, P<0.001) and the number of neonatal deaths has significantly decreased (39 to 10%, P<0.001).

CONCLUSION

The survival and the voluntary termination of fetuses with prenatally detected congenital heart diseases are strongly influenced by disease severity and by associated extracardiac or chromosomal anomalies, or both. Over 12 years, the spectrum of fetal congenital heart disease has changed and their outcome has significantly improved.

Critical heart defects--the diagnostic challenge

Infants with potentially life threatening congenital heart defects (CHDs) are discharged from hospital after birth with the condition unrecognized. Improved prenatal ultrasound imaging and universal pulse oximetry screening of babies in nurseries are strategies that probably most would contribute to avoid such defects to be missed.

CONCLUSION

In general combining first day of life pulse oximetry, clinical examination and echocardiography before discharge in suspect cases is a rational strategy for early postnatal detection of heart defects. Universal echocardiography screening of newborns may be too resource consuming to be cost-effective.

'Big-eyed frog' sign on spatiotemporal image correlation (STIC) in the antenatal diagnosis of transposition of the great arteries

OBJECTIVE

To determine the value of simultaneous visualization of the cross-sectional view of both atrioventricular (AV) valves, the pulmonary artery and the aorta (en-face view of the AV valves and great vessels) in the identification of fetuses with transposition of the great arteries (TGA).

METHODS

This was a retrospective analysis of volume datasets obtained with the spatiotemporal image correlation (STIC) technique from 56 fetuses with and 30 fetuses without congenital heart defects. Volume datasets were reviewed offline to compare the en-face view of the AV valves and great vessels between fetuses with normal echocardiography and those with TGA.

RESULTS

The en-face view of both AV valves and great vessels in fetuses with TGA displayed the main pulmonary artery situated side-by-side with the aorta ('big-eyed frog' sign). In contrast, fetuses with normal hearts did not have this characteristic sonographic sign. This novel sonographic sign also helped to identify additional cases of TGA in 17 fetuses with complex heart defects.

CONCLUSION

The big-eyed frog sign may prove helpful in the prenatal diagnosis of TGA.

Decreasing number of deaths of infants with hypoplastic left heart syndrome

OBJECTIVE

To assess mortality rates and demographic characteristics for infants with hypoplastic left heart syndrome (HLHS) in California.

STUDY DESIGN

We used California death registry files from 1990 to 2004 to compare overall mortality and demographic characteristics between infants with HLHS (n = 856) who received surgical intervention and those who received comfort care. The California discharge database was used to calculate the annual incidence of disease and survival rates for infants with HLHS undergoing surgery between 1995 and 1999.

RESULTS

The annual number of deaths for infant with HLHS decreased by nearly 50% over the study period, even though the incidence of the disease remained constant during this period. For all deaths, the proportion of infants receiving comfort care decreased significantly over time compared with those infants who underwent surgery. Although the total number of deaths in infants with HLHS who underwent surgical intervention increased, the mortality rate for this cohort decreased. Interstage unexpected mortality and the median age at death both increased in the infants who underwent surgery.

CONCLUSIONS

Over the study period of 1990 to 2004 in California, fewer families chose comfort care for infants diagnosed with HLHS, and the number of deaths for those infants who underwent surgical intervention increased. These changes likely reflect improved treatment outcomes and an increased number of families desiring surgical intervention in higher-risk infants.

Application of automated sonography on 4-dimensional volumes of fetuses with transposition of the great arteries

OBJECTIVE

The purpose of this study was to assess, in second-trimester fetuses with transposition of the great arteries (TGA), the performance of software (sonographically based volume computer-aided analysis) that automatically retrieves diagnostic cardiac planes from a 4-dimensional volume of the fetal chest obtained with spatiotemporal image correlation.

METHODS

We retrospectively evaluated the 4-dimensional spatiotemporal image correlation volumes of 12 fetuses with TGA (complete TGA, 10 cases; correct TGA, 2 cases). The data were analyzed to determine whether the target diagnostic planes, that is, cardiac plane 1 (left ventricle outflow tract) and cardiac plane 2 (right ventricle outflow tract), were correctly identified in at least 1 of the 7 automatically generated tomographic sonographic image displays and whether they allowed diagnosis of TGA.

RESULTS

In 9 of 10 fetuses with complete TGA, target diagnostic cardiac plane 1 showed a branching arterial vessel (pulmonary artery) arising from the left ventricle, whereas in 7 of 10 fetuses, the aorta arising from the right ventricle was shown. In both cases with correct TGA, the pulmonary artery starting from the morphologic left ventricle was shown, whereas in 1 of 2, the connection of the aorta with the morphologic right ventricle was found. In all of the fetuses with TGA, a ventricular arterial connection anomaly was shown in either cardiac plane 1 or 2.

CONCLUSIONS

This automatic approach shows good retrieval of diagnostic cardiac planes in fetuses with TGA, which may improve diagnostic efficacy for this disease.

Sexual behavior and reproductive concerns among adolescents and young adults with congenital heart disease

OBJECTIVES

To examine the sexual behaviors and reproductive concerns among patients with moderate to complex congenital heart disease (CHD).

BACKGROUND

There is a growing need to understand and address the psychosocial issues for older adolescents and young adults with CHD. Emerging sexuality is an issue for this age group and pregnancy for many women with CHD is risky. But, patients' sexual behavior and reproductive concerns have not been studied.

METHODS

Young adults (19-20 years old; n=212) and adolescents (16-18 years old; n=144) with moderate to complex CHD reported their sexual behaviors and reproductive concerns. Data were compared to normative samples from Canada and the United States.

RESULTS

Few adolescents (14%) but many young adults (48%) with CHD were sexually active (at least one partner in the previous 3 months). These rates were lower than those of their healthy peers. Among the sexually active patients, 36% of the young adults and 72% of the adolescents engaged in one or more types of potentially risky sexual behavior (i.e., two or more partners in the past 3 months, questionable birth control, using drugs or alcohol before sex at least sometimes). Women with complex CHD had the highest levels of concern regarding their fertility and risk of genetic transmission of CHD, as well as concerns about adverse effects of pregnancy on their own health.

CONCLUSIONS

Sexual health should be discussed with adolescents and young adults with CHD. Particular attention should be given to discussing sexual health with women who have complex CHD.

An echocardiographic study of diagnostic accuracy, prediction of surgical approach, and outcome for fetuses diagnosed with discordant ventriculo-arterial connections

Our aims were to examine the diagnostic accuracy of prenatal diagnosis of concordant atrioventricular and discordant ventriculo-arterial connections, the accuracy of predictions made concerning the postnatal surgical approach, and a description of the different subtypes related to outcome. All fetuses were evaluated at a tertiary centre for fetal cardiology between January, 1994, and December, 2003. In this period, we identified congenitally malformed hearts in 1,835 fetuses, of whom 56 (3%) met the criterions of inclusion. Of the total, 30 (54%) had an intact ventricular septum, 9 (16%) had an associated ventricular septal defect, 7 (13%) had a ventricular septal defect and pulmonary stenosis, 1 (2%) had pulmonary stenosis and an intact ventricular septum, 8 (14%) had a ventricular septal defect and aortic coarctation, and 1 (2%) had coarctation of the aorta with an intact ventricular septum. All the discordant ventriculo-arterial connections were correctly identified. For associated ventricular septal defects, the diagnostic sensitivity was 96%, with specificity of 88%, positive predictive value of 85%, and negative predictive value of 97%. For aortic coarctation, the sensitivity was 100%, specificity 96%, positive predictive value 82%, and negative predictive value 100%. The prediction of the surgical approach was accurate in 41 of 48 cases (85%). For those fetuses with pulmonary stenosis and ventricular septal defect, the ratio of the diameters of the pulmonary trunk was shown to be helpful in predicting the possibility of an arterial switch as opposed to the Rastelli type of repair. Of the 49 liveborn infants, 46 were alive at 30 days (94%, with 95% confidence intervals from 83 to 99%), and 43 at one year (88%, 95% confidence intervals from 75 to 95%). Deaths were mainly related to the anatomy of the coronary arteries, and associated cardiac lesions.