Fetal diagnosis and management of pulmonary artery sling: A case series.

OBJECTIVE: Pulmonary artery sling is a rare congenital anomaly accounting for 2% of all patients with vascular anomalies that cause airway obstruction. In the normal heart, the left (LPA) and right (RPA) pulmonary arteries arise in the intrapericardial space. However, in the pulmonary artery sling, the LPA trunk arises in the extrapericardial space from the posterior aspect of the mid RPA and courses posterior to the trachea causing tracheal compression and, at times, bronchial compression. While a full spectrum of congenital cardiac pathology can be identified before birth, only a few case reports document the prenatal diagnosis of an Left pulmonary artery sling (LPAS). METHOD: We retrospectively identified all cases of prenatal LPAS from three Canadian fetal cardiology centers (2015-2022). RESULTS: Using the 3-vessel-tracheal view via fetal echocardiography (FE), four fetuses from three pregnancies demonstrated abnormal origin of the LPA from RPA and echogenic trachea. In one of two affected monochorionic twins coronal imaging demonstrated a significant narrowing of the large airways consistent with significant airway obstruction. CONCLUSION: Prenatal detection of LPAS by FE is possible and should prompt an evaluation for airway obstruction in the coronal view. Investigating associated lesions and genetic testing are recommended for informed shared decision making.

Natural History of Secundum ASD in Preterm and Term Neonates: A Comparative Study.

Atrial septal defects (ASDs) are common in neonates. Although past studies suggest ASDs  ≥ 3 mm in term neonates (TNs) are less likely to close, there is paucity of data regarding the natural history in preterm neonates (PNs), information that would inform surveillance. We sought to compare spontaneous closure rates and need for intervention for ASDs in TNs/near term (≥ 36 weeks) versus PNs (< 36 weeks). We included all TNs and PNs who underwent echocardiography at ≤ 1 month between 2010 and 2018 in our institution with an ASD ≥ 3 mm, without major congenital heart disease, and with repeat echocardiogram(s). Spontaneous resolution was defined as size diminution to < 3 mm or closure. We included 156 TNs (mean gestational age at birth 38.6 ± 1.4 weeks) and 156 PNs (29.6 ± 3.7 weeks) with a mean age at follow-up of 16 ± 19 and 15 ± 21 months, respectively (p = 0.76). Based on maximum color Doppler diameter, in TNs, ASD resolution occurred in 95% of small (3-5 mm), 87% of moderate (5.1-8 mm), and 60% of large (> 8 mm) defects; whereas, in PNs, resolution occurred in 79% of small, 76% of moderate, and 33% of large ASDs. There was a significant association between size and ASD resolution in TNs (p = 0.003), but not PNs (p = 0.17). Overall, ASD resolution rate was higher in TNs (89%) versus PNs (78%) (p = 0.009), and fewer TNs (1%) compared to PNs (7%) required ASD intervention (p = 0.02). Most ASDs identified in TNs and PNs spontaneously resolve. PNs, however, demonstrate lower ASD resolution and higher intervention rates within all size groups. These data should inform follow-up of affected neonates.

Lower Socioeconomic Status is Associated with an Increased Incidence and Spectrum of Major Congenital Heart Disease and Associated Extracardiac Pathology.

Several studies have suggested an inverse relationship between lower socioeconomic status (SES) and the incidence of congenital heart disease (CHD) among live births. We sought to examine this relationship further in a Canada-wide population study, exploring CHD subtypes, trends, and associated noncardiac abnormalities. Infants born in Canada (less Quebec) from 2008 to 2018 with CHD requiring intervention in the first year were identified using ICD-10 codes through the Canadian Institute for Health Information Discharge Abstract Database. Births of CHD patients were stratified by SES (census-based income quintiles) and compared against national birth proportions using X2 tests. Proportions with extracardiac defects (ED) and nonlethal genetic syndromes (GS) were also explored. From 2008 to 2018, 7711 infants born with CHD were included. The proportions of major CHD distributed across SES quintiles were 27.1%, 20.1%, 19.2%, 18.6%, and 15.0% from lowest to highest, with significant differences relative to national birth proportions (22.0%, 20.0%, 20.6%, 20.7%, and 16.7% from lowest (1) to highest (5)) (p < 0.0001). No temporal trends in the CHD proportions across SES categories were observed over the study period. The distribution across SES quintiles was different only for specific CHD subtypes (double-outlet right ventricle (n = 485, p = 0.03), hypoplastic left heart syndrome (n = 547, p = 0.006), heterotaxy (n = 224, p = 0.03), tetralogy of Fallot (n = 1007, p = 0.008), truncus arteriosus (n = 126, p < 0.0001), and ventricular septal defect (n = 1916, p < 0.0001)), with highest proportions observed in the lowest quintile. The proportion of the total population with ED but not GS was highest in lower SES quintiles (< 0.0001) commensurate with increased proportion of CHD. Our study suggests a negative association between SES and certain CHD lesions and ED.

Targeted Neonatal Echocardiography Performed by Nurse Practitioners in the NICU: Attitudes and Perceptions of the Healthcare Team.

BACKGROUND: Targeted neonatal echocardiography (TNE) and hemodynamic consultation have typically been performed by physicians. The Stollery Children's Hospital neonatal intensive care unit (NICU) expanded their TNE training program to include neonatal nurse practitioners (NNPs), the first in North America. PURPOSE: This study examines the thoughts and perceptions of clinicians about the incorporation of NNPs providing TNE and hemodynamic consultation and investigates key facilitators and challenges for consideration when planning future training, expansion of service in Edmonton, or beyond. METHODS: In this descriptive study using qualitative methodology, purposive sampling was used to invite NICU clinicians to participate. Using a semistructured topic guide, a focus group and 2 individual interviews were conducted. RESULTS: Participants were supportive of NNPs. Advantages included increased access to service, acquisition and retention of skills, provision of patient-centered care, and leveraged interpersonal relationships in the decision-making process. Key aspects of program expansion included climate and culture of the NICU, presence of adequate patient volume, and resources to support training. IMPLICATIONS FOR PRACTICE AND RESEARCH: Support across disciplines and the collaborative working nature of the NICU are key factors in the success of the program's development and implementation. Benefits of having NNPs on the TNE team were clearly expressed. Benefits to the health system included rapid access to hemodynamic information allowing for care based on specific pathophysiology and additional local capacity to perform TNE and reducing demand on other trained providers. Additional research could consider parental views of NNPs performing TNE and hemodynamic consultation as well as the accuracy of diagnosis between the NNPs and physician group.

Third Trimester Umbilical Arterial Pulsatility Index is Associated with Neurodevelopmental Outcomes at 2-Years in Major Congenital Heart Disease.

Major congenital heart disease (CHD) is associated with impaired neurodevelopment (ND), partly from prenatal insults. In this study we explore associations between 2nd and 3rd trimester umbilical (UA) and middle cerebral artery (MCA) pulsatility index (PI = systolic-diastolic velocities/mean velocity) in fetuses with major CHD and 2-year ND and growth outcomes. Eligible patients included those with a prenatal diagnosis of CHD from 2007 to 2017 without a genetic syndrome who underwent previously defined cardiac surgeries and 2-year biometric and ND assessments in our program. UA and MCA-PI Z-scores at fetal echocardiography were examined for relationships with 2-year Bayley Scales of Infant and Toddler Development and biometric Z-scores. Data from 147 children was analyzed. Second and 3rd trimester fetal echocardiograms were performed at 22.4 ± 3.7 and 34.7 ± 2.9 weeks (mean ± SD), respectively. Multivariable regression analysis showed an inverse relationship between 3rd trimester UA-PI for all CHD and cognitive - 1.98 (- 3.37, - 0.59), motor - 2.57 (- 4.15, - 0.99), and language - 1.67 (- 3.3, - 0.03) (effect size and 95th confidence interval) ND domains (p < 0.05), with the strongest relationships in the single ventricle and hypoplastic left heart syndrome subgroups. No association was found for 2nd trimester UA-PI or any trimester MCA-PI and ND or between UA or MCA-PI and 2-year growth parameters. Increased 3rd trimester UA-PI, reflecting an altered late gestation fetoplacental circulation, relates to worse 2-year ND in all domains.

Impact of Socioeconomic Status, Race and Ethnicity, and Geography on Prenatal Detection of Hypoplastic Left Heart Syndrome and Transposition of the Great Arteries.

BACKGROUND: Prenatal detection (PND) has benefits for infants with hypoplastic left heart syndrome (HLHS) and transposition of the great arteries (TGA), but associations between sociodemographic and geographic factors with PND have not been sufficiently explored. This study evaluated whether socioeconomic quartile (SEQ), public insurance, race and ethnicity, rural residence, and distance of residence (distance and driving time from a cardiac surgical center) are associated with the PND or timing of PND, with a secondary aim to analyze differences between the United States and Canada. METHODS: In this retrospective cohort study, fetuses and infants <2 months of age with HLHS or TGA admitted between 2012 and 2016 to participating Fetal Heart Society Research Collaborative institutions in the United States and Canada were included. SEQ, rural residence, and distance of residence were derived using maternal census tract from the maternal address at first visit. Subjects were assigned a SEQ z score using the neighborhood summary score or Canadian Chan index and separated into quartiles. Insurance type and self-reported race and ethnicity were obtained from medical charts. We evaluated associations among SEQ, insurance type, race and ethnicity, rural residence, and distance of residence with PND of HLHS and TGA (aggregate and individually) using bivariate analysis with adjusted associations for confounding variables and cluster analysis for centers. RESULTS: Data on 1862 subjects (HLHS: n=1171, 92% PND; TGA: n=691, 58% PND) were submitted by 21 centers (19 in the United States). In the United States, lower SEQ was associated with lower PND in HLHS and TGA, with the strongest association in the lower SEQ of pregnancies with fetal TGA (quartile 1, 0.78 [95% CI, 0.64-0.85], quartile 2, 0.77 [95% CI, 0.64-0.93], quartile 3, 0.83 [95% CI, 0.69-1.00], quartile 4, reference). Hispanic ethnicity (relative risk, 0.85 [95% CI, 0.72-0.99]) and rural residence (relative risk, 0.78 [95% CI, 0.64-0.95]) were also associated with lower PND in TGA. Lower SEQ was associated with later PND overall; in the United States, rural residence and public insurance were also associated with later PND. CONCLUSIONS: We demonstrate that lower SEQ, Hispanic ethnicity, and rural residence are associated with decreased PND for TGA, with lower SEQ also being associated with decreased PND for HLHS. Future work to increase PND should be considered in these specific populations.

Extra-cardiac diagnoses and postnatal outcomes of fetal tetralogy of fallot.

OBJECTIVE: Past studies of fetal tetralogy of fallot (ToF) have reported extra-cardiac anomalies (ECAs) in 17%-45%, genetic syndromes in as low as 20% and poor postnatal outcomes. This study sought to examine these factors in a contemporary cohort. METHODS: A retrospective review examining 83 fetuses with ToF diagnosed 2012-2019. Referral indication, ToF subtype, additional cardiac, extra-cardiac and genetic diagnoses, pregnancy outcomes and survival were documented. RESULTS: The mean gestational age at diagnosis was 23 ± 4 weeks. Of 94% (78/83) with genetic testing (GT), 30% (23/78, 95%CI 21%-40%) had genetic anomalies (GA), including Trisomy 21 (39%, 9/23), 22q11 deletion (35%, 8/23), Trisomy 13 or 18 (17%, 4/23) and 9% (2/23) others. A further 4% (3/78) had VACTERL association. Forty-one percent (34/83, 95%CI 31%-52%) had ≥1 major ECA of whom 41% (14/34) also had a genetic anomaly. OUTCOMES: 22% (18/83) pregnancy termination, 5% (4/83) intrauterine death and 72% (60/83) live birth. Of live births, 3% (2/60) experienced neonatal death, 7% late death (4/60) and 90% (54/60) were alive at last follow-up (mean age 3.5 ± 2.4 years). CONCLUSION: In a cohort of fetuses with ToF and high rates of GT, compared to previous reports, GA were more common and there were similar rates of ECAs.

Trends in the Prenatal Detection of Major Congenital Heart Disease in Alberta From 2008-2018.

OBJECTIVE: The effect of expanded obstetrical ultrasound cardiac views on the diagnosis of fetal congenital heart disease (CHD) has not been fully examined at a population level. We hypothesized there has been a significant increase in the prenatal detection of CHD in Alberta, particularly for CHD associated with cardiac outflow tract and 3-vessel view abnormalities. METHODS: Using provincial databases, we retrospectively identified all fetuses and infants diagnosed between 2008 and 2018 in Alberta with major CHD requiring surgical intervention within the first postnatal year. We evaluated individual lesions and categorized CHDs into the following groups based on the obstetrical ultrasound cardiac views required for detection: (1) 4-chamber view (e.g., hypoplastic left heart syndrome, Ebstein's anomaly, single ventricle); (2) outflow tract view (e.g., tetralogy of Fallot, d-transposition, truncus arteriosus); (3) 3-vessel or other non-standard cardiac views (e.g., coarctation, anomalous pulmonary veins); and (4) isolated ventricular septal defects using any view. RESULTS: Of 1405 cases of major CHD, 814 (58%) were prenatally diagnosed. Over the study period, prenatal detection increased in all groups, with the greatest increase observed for groups 1 and 2 (75%-88%; P = 0.008 and 56%-79%; P = 0.0002, respectively). Although rates of prenatal detection also increased for groups 3 and 4 (27%-43%; P = 0.007 and 13%-30%; P = 0.04, respectively), fewer than half of the cases in each group were detected prenatally, even in more recent years. CONCLUSIONS: While rates of prenatal detection of CHD have significantly improved during the past decade, many defects with abnormal 3-vessel and non-standard views, as well as isolated ventricular septal defects, still go undetected.

Prenatal features, associated co-morbidities and clinical course of agenesis of the ductus venosus in the current era.

OBJECTIVES: Agenesis of the ductus venosus (ADV) has been associated with additional anomalies in up to 83% of cases. We sought to investigate characteristics, co-morbidities and outcomes of ADV in the current era. We hypothesized that rates of cardiac and non-cardiac diagnoses and survival would be higher, due to advances in genetic testing, prenatal diagnosis and surveillance. METHODS: A retrospective series of cases diagnosed at our institution from 2007 to 2018 were identified by searching our database. Cardiac and obstetric charts were reviewed for cardiac and extra-cardiac anomalies, genetic results and outcomes. RESULTS: Fourteen cases were diagnosed at a mean gestational age of 23.9 weeks (range 13-33). All had associated genetic, cardiac or extra-cardiac anomalies. Eight (57%) had cardiac anomalies and one other developed cardiomyopathy by 6 months. Extra-cardiac anomalies were present in 93% (13/14) and genetic diagnoses made in 75% (6/8) of those tested. Cardiac output Z-scores were >2 in 60% (6/10) prior to delivery. Two had hydrops, there was one intra-uterine death, 13 live-births and two neonatal deaths. CONCLUSION: Our cohort had more associated diagnoses and a lower mortality than previously reported. In our experience, high output occurs frequently, however with a relatively low risk of hydrops and intrauterine death.

Fetal double outlet right ventricle without heterotaxy syndrome: Diagnostic spectrum, associated extracardiac pathology and clinical outcomes.

OBJECTIVES: To document the clinical spectrum and outcomes of fetal double outlet right ventricle (DORV) without heterotaxy in a recent diagnostic era. METHODS: Prenatal cases of DORV consecutively diagnosed from 2007 to 2018 were retrospectively identified. Clinical records, including details regarding genetic testing and pre and postnatal imaging were reviewed. RESULTS: DORV was diagnosed in 99 fetuses without heterotaxy. The most common anatomic subtype was subaortic ventricular septal defect (VSD) and normally related great arteries with (n = 45, 45%) or without (n = 13, 13%) pulmonary stenosis. The remainder had a subpulmonic VSD with transposed great arteries (n = 15, 15%), atrioventricular valve atresia (n = 24, 24%), or remote VSD (n = 2, 2%). A genetic diagnosis was found in 32 (34%) of 93 tested. Major extracardiac anomalies were found in 40 (40%), including 17/24 (71%) with and 22/69 (32%) without an abnormal karyotype, with VACTERL association in 9. Genetic and/or extracardiac pathology was identified in 37/58 (64%) with a subaortic VSD, 5/15 (33%) with a subpulmonic VSD, 9/24 (38%) of those with AV valve atresia and 2/2 (100%) with a remote VSD. A genetic abnormality was a significant predictor of fetal demise (9/37 vs 1/62 p < 0.01) or pregnancy termination (12/35 vs 9/64 p = 0.03). CONCLUSIONS: Fetal DORV is associated with a high rate of genetic abnormalities and extracardiac pathology. The presence of genetic abnormalities impacts prenatal outcomes and parental decision-making.

Influence of extreme prematurity and bronchopulmonary dysplasia on cardiac function.

OBJECTIVE: Prematurity and bronchopulmonary dysplasia (BPD) are associated with poorly understood abnormalities of ventricular function. We therefore comprehensively compared biventricular function in infants with and without BPD. METHODS: Prospective observational study in extremely preterm infants with (n = 20) and without (n = 38) BPD using conventional and advanced echocardiography at 28 days (T1) and near-term (T2). RESULTS: Infants with BPD had lower birth gestational age (26.7±1.9 vs 27.4±1.1 weeks, p = 0.047) and weight (884±207 vs 1108±190 g, p = 0.0001). BPD was associated with larger right ventricles (RV) and reduced RV systolic strain rate at T1 and pulmonary hypertensive indicators at T2 (pulmonary artery acceleration time BPD 51±17 vs no BPD 63±12 ms, p = 0.017). At T1/T2, infants with BPD had lower RV tissue Doppler velocities (e', a' and s) and higher E/e' ratios (T1: BPD 10.4±2.4 vs no BPD 6.2±3.1 cm/sec, p = 0.001; T2: BPD 8.0±3.1 vs no BPD 5.6±2.6 cm/sec, p = 0.02), altered LV diastolic function (apical circumferential T1 early diastolic strain rate BPD 2.8±0.8 vs no BPD 3.6±1.0 /sec, p = 0.04; T2 late diastolic strain rate, BPD 2.29 ± 0.99 vs no BPD 1.67±0.84 /sec, p = 0.03) and LV rotational mechanics (T1: twist rate BPD 90±16 vs no BPD 130±48 deg/sec, p = 0.008; untwist rate (UTR) BPD -69±90 vs no BPD -147±68 deg/sec, p = 0.008; torsion BPD 2.78±0.56 vs no BPD 4.48±1.74 deg/cm, p = 0.009; and T2: UTR BPD -132±69 vs no BPD -179±57 deg/sec, p = 0.013). CONCLUSION: BPD is associated with altered RV diastolic function that persists near term, with elevated pulmonary vascular resistance, and with persistent alterations in LV apical strain rate and rotational mechanics.

Fetal Diagnosis is Associated with Improved Perioperative Condition of Neonates Requiring Surgical Intervention for Coarctation.

To define the relative importance of fetal diagnosis and comorbidities in severity of preoperative compromise, outcomes and hospitalization in neonatal coarctation of the aorta (CoA). Retrospective comparison of preoperative condition and postoperative course of neonates prenatally (PreDx n = 48) or postnatally diagnosed (PostDx n = 67) with CoA. Congenital and non-congenital comorbidities were adjusted for. Postnatal diagnosis was associated with preoperative mortality (n = 2), and severe acidosis (lactate > 5 mM or pH < 7.20) on multivariate analysis (OR 4.2 (1.3-14.4, p = 0.02), with extracardiac congenital anomalies also a risk factor (OR 3.2 (1.03-10, p = 0.044). Median age at operation was delayed in the PostDx group (PreDx 6.5 days (IQR 4-9) vs PostDx 10 days (IQR 6-17)). Only comorbid left heart disease and extracardiac congenital anomalies were associated with prolonged total length of hospital stay. Prenatal diagnosis is the major adjustable risk factor affecting preoperative condition in critical CoA but does not reduce length of stay.

Cardiac function and dysfunction in the fetus.

Evaluation of fetal cardiac function is one of the most important components of fetal echocardiography. Fetal cardiac dysfunction is closely linked to risk of intrauterine fetal demise, in many, but not all cases is indicative of worse postnatal prognosis and may prompt the use of medications or interventions to optimize outcomes. There may be implications for termination versus continuation of pregnancy, an indication for early delivery, a change in location and even mode of delivery. In extreme cases, fetal cardiac dysfunction may prompt prenatal or early neonatal listing for cardiac transplantation. There are several important differences between the fetal and postnatal circulatory physiology which affect echocardiographic assessment of cardiac dysfunction. In this review, we examine the echocardiographic findings according to their underlying pathophysiology with reference to common causes.

Postnatal neonatal myocardial adaptation is associated with loss of tolerance to tachycardia: a simultaneous invasive and noninvasive assessment.

Doppler studies at rest suggest left ventricular (LV) diastolic function rapidly improves from the neonate to infant. Whether this translates to its response to hemodynamic challenges is uncertain. We sought to explore the impact of early LV maturation on its ability to tolerate atrial tachycardia. As tachycardia reduces filling time, we hypothesized that the neonatal LV would be less tolerant of atrial tachycardia. Landrace cross piglets of two age groups (1-3 days; NPs; 14-17 days, YPs; n = 7/group) were instrumented for an atrial pacing protocol (from 200 to 300 beats/min) and assessed by invasive monitoring and echocardiography. NPs maintained their LV output and blood pressure, whereas YPs did not. Although negative dP/dt in NPs at baseline was lower than that of YPs (-1,599 ± 83 vs. -2,470 ± 226 mmHg/s, respectively, P = 0.007), with increasing tachycardia negative dP/dt converged between groups and was not different. Both groups had similar preload reduction during tachycardia; however, NPs maintained shortening fraction while YPs decreased (NPs: 35.4 ± 1.4 vs. 31.8 ± 2.2%, P = 0.35; YPs: 31.4 ± 0.8 vs. 22.9 ± 0.8%, P < 0.001). Contractility measures did not differ between groups. Peak LV twist and untwisting rate also did not differ; however, NPs tended to augment LV twist through increased apical rotation and YPs through increasing basal rotation (P = 0.009). The NPs appear more tolerant of atrial tachycardia than the YPs. They have at least similar diastolic performance, enhanced systolic performance, and different LV twist mechanics, which may contribute to improved tachycardia tolerance of NPs.

Diagnosis and treatment of fetal cardiac disease: a scientific statement from the American Heart Association.

BACKGROUND: The goal of this statement is to review available literature and to put forth a scientific statement on the current practice of fetal cardiac medicine, including the diagnosis and management of fetal cardiovascular disease. METHODS AND RESULTS: A writing group appointed by the American Heart Association reviewed the available literature pertaining to topics relevant to fetal cardiac medicine, including the diagnosis of congenital heart disease and arrhythmias, assessment of cardiac function and the cardiovascular system, and available treatment options. The American College of Cardiology/American Heart Association classification of recommendations and level of evidence for practice guidelines were applied to the current practice of fetal cardiac medicine. Recommendations relating to the specifics of fetal diagnosis, including the timing of referral for study, indications for referral, and experience suggested for performance and interpretation of studies, are presented. The components of a fetal echocardiogram are described in detail, including descriptions of the assessment of cardiac anatomy, cardiac function, and rhythm. Complementary modalities for fetal cardiac assessment are reviewed, including the use of advanced ultrasound techniques, fetal magnetic resonance imaging, and fetal magnetocardiography and electrocardiography for rhythm assessment. Models for parental counseling and a discussion of parental stress and depression assessments are reviewed. Available fetal therapies, including medical management for arrhythmias or heart failure and closed or open intervention for diseases affecting the cardiovascular system such as twin-twin transfusion syndrome, lung masses, and vascular tumors, are highlighted. Catheter-based intervention strategies to prevent the progression of disease in utero are also discussed. Recommendations for delivery planning strategies for fetuses with congenital heart disease including models based on classification of disease severity and delivery room treatment will be highlighted. Outcome assessment is reviewed to show the benefit of prenatal diagnosis and management as they affect outcome for babies with congenital heart disease. CONCLUSIONS: Fetal cardiac medicine has evolved considerably over the past 2 decades, predominantly in response to advances in imaging technology and innovations in therapies. The diagnosis of cardiac disease in the fetus is mostly made with ultrasound; however, new technologies, including 3- and 4-dimensional echocardiography, magnetic resonance imaging, and fetal electrocardiography and magnetocardiography, are available. Medical and interventional treatments for select diseases and strategies for delivery room care enable stabilization of high-risk fetuses and contribute to improved outcomes. This statement highlights what is currently known and recommended on the basis of evidence and experience in the rapidly advancing and highly specialized field of fetal cardiac care.

Maternal hypothyroidism may be associated with CHD in offspring.

OBJECTIVES: This study tested whether mothers with maternal hypothyroidism have increased odds of CHD in their offspring, and examined the relationship between CHD, maternal thyroid function, and nausea and vomiting in pregnancy. BACKGROUND: Maternal hypothyroidism increases the risk for foetal demise and prematurity and can have a negative impact on neurodevelopment. Prior studies have postulated a relationship between maternal thyroid function, CHD, and maternal nausea and vomiting in pregnancy. METHODS: A cross-sectional case-control study was conducted over a 17-month period to obtain a history of maternal thyroid status and nausea and vomiting in pregnancy. Paediatric echocardiograms were evaluated for CHD by a blinded paediatric cardiologist. Logistic regression analysis was performed to examine the association between CHD and maternal hypothyroidism. RESULTS: Of the 998 maternal-child pairs, 10% (98/998) of the mothers reported a history of prenatal hypothyroidism. The overall prevalence of CHD in the study sample was 63% (630/998). Mothers with a history of hypothyroidism were significantly more likely to have offspring with CHD compared with mothers without a history of hypothyroidism (72 versus 62%; p=0.04). The adjusted odds ratio (95% confidence interval) of CHD in offspring associated with reported maternal hypothyroidism was 1.68 (1.02-2.78). CONCLUSION: This study suggests that maternal hypothyroidism is a risk factor for the development of CHD. Further prospective investigations are necessary to confirm this association and delineate pathogenic mechanisms.

Diagnosis of congenital heart disease in an era of universal prenatal ultrasound screening in southwest Ohio.

OBJECTIVES: Diagnostic ultrasound is widespread in obstetric practice, yet many babies with major congenital heart disease remain undiagnosed. Factors affecting prenatal diagnosis of major congenital heart disease are not well understood. This study aims to document prenatal detection rates for major congenital heart disease in the Greater Cincinnati area, and identify factors associated with lack of prenatal diagnosis. METHODS: All living infants diagnosed with major congenital heart disease by 4 months of age at our centre were prospectively identified. Prenatal care data were obtained by parent interview. Neonatal records were reviewed for postnatal data. Obstetricians were contacted for diagnostic ultrasound data. RESULTS: A total of 100 infants met the inclusion criteria. In all, 95 infants were analysed, of whom 94 were offered diagnostic ultrasound. In all, 41 had a prenatal diagnosis of major congenital heart disease. The rate of prenatal detection varied by cardiac lesion, with aortic arch abnormalities, semilunar valve abnormalities, and venous anomalies going undetected in this sample. Among subjects without prenatal detection, the highest proportion consisted of those having Level 1 diagnostic ultrasound only (66%). Prenatal detection was not significantly influenced by maternal race, education level, income, or insurance type. CONCLUSIONS: Despite nearly universal diagnostic ultrasound, detection rates of major congenital heart disease remain low in southwest Ohio. An educational outreach programme including outflow tract sweeps for community-level obstetrical personnel may improve detection rates.