The impact of prenatal diagnosis of complex congenital heart disease on neonatal outcomes

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.

A population-based study of the association of prenatal diagnosis with survival rate for infants with congenital heart defects

Prenatal diagnosis has been shown to improve preoperative morbidity in newborns with congenital heart defects (CHDs), but there are conflicting data as to the association with mortality. We performed a population-based, retrospective, cohort study of infants with prenatally versus postnatally diagnosed CHDs from 1994 to 2005 as ascertained by the Metropolitan Atlanta Congenital Defects Program. Among infants with isolated CHDs, we estimated 1-year Kaplan-Meier survival probabilities for prenatal versus postnatal diagnosis and estimated Cox proportional hazard ratios adjusted for critical CHD status, gestational age, and maternal race/ethnicity. Of 539,519 live births, 4,348 infants had CHDs (411 prenatally diagnosed). Compared with those with noncritical defects, those with critical defects were more likely to be prenatally diagnosed (58% vs 20%, respectively, p <0.001). Of the 3,146 infants with isolated CHDs, 1-year survival rate was 77% for those prenatally diagnosed (n = 207) versus 96% for those postnatally diagnosed (n = 2,939, p <0.001). Comparing 1-year survival rate among those with noncritical CHDs alone (n = 2,455) showed no difference between prenatal and postnatal diagnoses (96% vs 98%, respectively, p = 0.26), whereas among those with critical CHDs (n = 691), prenatally diagnosed infants had significantly lower survival rate (71% vs 86%, respectively, p <0.001). Among infants with critical CHDs, the adjusted hazard ratio for 1-year mortality rate for those prenatally versus postnatally (reference) diagnosed was 2.51 (95% confidence interval 1.72 to 3.66). In conclusion, prenatal diagnosis is associated with lower 1-year survival rate for infants with isolated critical CHDs but shows no change for those with isolated noncritical CHDs. More severe disease among the critical CHD subtypes diagnosed prenatally might explain these findings.

Relation of prenatal diagnosis with one-year survival rate for infants with congenital heart disease

Prenatal diagnosis of congenital heart defects (CHDs) is increasingly common, but it is still unclear whether it translates to improved postoperative outcomes. We performed a retrospective cohort study of all infants (aged <1 year) who underwent surgery for CHDs from 2006 to 2011 at a single institution. Primary outcomes were in-hospital and 1-year mortality rates. Secondary outcomes were readmission within 30 days of discharge, postoperative length of intensive care unit and hospital stay, unplanned reoperation, and extracorporeal membrane oxygenation use. We used chi-square analyses, Wilcoxon rank-sum tests, Kaplan-Meier survival curves, and adjusted Cox proportional hazards models to compare outcomes. Of the 1,642 patients with CHDs, 539 (33%) were diagnosed prenatally. Patients with prenatal diagnoses were of a younger age and less weight at the time of surgery, had greater Risk Adjustment for Congenital Heart Surgery scores, and were more likely to be white, to have an identified syndrome, or to be born at term. Compared with those diagnosed postnatally, those diagnosed prenatally had a significantly higher unadjusted 1-year mortality rate (11% vs 5.5%, respectively, p = 0.03). Controlling for weight, surgical severity, race, age at surgery, prematurity, and the presence or absence of genetic syndrome, patients with prenatal diagnoses had significantly greater mortality at 1 year (adjusted hazard ratio 1.5, p = 0.03), as well as significantly longer intensive care unit and hospital stays. Infants with CHDs diagnosed prenatally had worse outcomes compared with those diagnosed postnatally. Prenatal diagnosis likely captures patients with more severe phenotypes within given surgical risk categories and even within diagnoses and thus may be an important prognostic factor when counseling families.

Development and validation of a fetal cardiovascular disease severity scale

Prenatal heart disease spans the spectrum of severity from very mild to severe life-threatening conditions. An accepted scale for grading fetal cardiovascular disease severity would aid in anomaly standardization, counseling, and future research. The Fetal Cardiovascular Disease Severity Scale with seven severity grades ranging from mild (grade 1) to severe (grade 7) disease was developed. Severity grade relates to the cardiovascular condition diagnosed by fetal echocardiography, with factors including postnatal intervention, number of interventions anticipated, likelihood of two-ventricle repair versus single-ventricle palliation, and overall prognosis. A survey describing 25 cardiac anomalies was offered to fetal cardiologists at six institutions for validation of scale reliability among practitioners. The study participants graded defects using this scale. A smaller group graded anomalies again more than 2 weeks after the initial survey. The intraclass correlation coefficient (ICC) was used to assess agreement of the respondents. The survey participants were 14 experienced fetal cardiologists: 9 from the Children's Hospital of Philadelphia (CHOP) and 5 from five additional institutions in the United States. The initial survey ICC was high [0.93; 95 % confidence interval (CI) 0.88-0.96]. The subanalysis showed a higher ICC for the participants outside CHOP (0.95; 95 % CI 0.91-0.98 vs. 0.92; 95 % CI 0.86-0.96, respectively). The ICCs were high for all the fetal cardiologists participating in the repeat evaluation, ranging from 0.92 to 0.99 (95 % CI 0.65-1.00). The Fetal Cardiovascular Disease Severity Scale demonstrated good inter- and intrarater reliability among experienced fetal cardiologists and is a valid tool for standardization of prenatal cardiac diagnostic assessment across institutions. The scale has applications for parental counseling and research in fetal cardiovascular disease.

A Simple Effective Protocol to Increase Prenatal Detection of Critical Congenital Heart Disease

Prenatal diagnosis of congenital heart disease (CHD) during routine obstetric sonography has been aptly named the sonographer’s Achilles heel. Although CHD occurs more commonly than any other major congenital abnormality, the detection rate remains low. The goal of this study was to improve the prenatal diagnosis of CHD during routine obstetric sonography through the development and implementation of a simple and effective screening protocol.

Prenatal diagnosis, birth location, surgical center, and neonatal mortality in infants with hypoplastic left heart syndrome

BACKGROUND

Most studies have not demonstrated improved survival after prenatal diagnosis of critical congenital heart disease, including hypoplastic left heart syndrome (HLHS). However, the effect of delivery near a cardiac surgical center (CSC), the recommended action after prenatal diagnosis, on HLHS mortality has been poorly investigated.

METHODS AND RESULTS

Using Texas Birth Defects Registry data, 1999 through 2007, which monitored >3.4 million births, we investigated the association between distance (calculated driving time) from birth center to CSC and neonatal mortality in 463 infants with HLHS. Infants with extracardiac birth defects or genetic disorders were excluded. The associations between prenatal diagnosis, CSC HLHS volume, and mortality were also examined. Neonatal mortality in infants born <10 minutes from a CSC was 21.0%, 10 to 90 minutes 25.2%, and >90 minutes 39.6% (P for trend <0.001). Prenatal diagnosis alone was not associated with improved survival (P=0.14). In multivariable analysis, birth >90 minutes from a CSC remained associated with increased mortality (odds ratio, 2.03; 95% confidence interval, 1.19-3.45), compared with <10 minutes. In subanalysis, birth >90 minutes from a CSC was associated with higher pretransport mortality (odds ratio, 6.69; 95% confidence interval, 2.52-17.74) and birth 10 to 90 minutes with higher presurgical mortality (odds ratio, 4.45; 95% confidence interval, 1.17-17.00). Higher surgical mortality was associated with lower CSC HLHS volume (odds ratio per 10 patients, 0.88; 95% confidence interval, 0.84-0.91).

CONCLUSIONS

Infants with HLHS born far from a CSC have increased neonatal mortality, and most of this mortality is presurgical. Efforts to improve prenatal diagnosis of HLHS and subsequent delivery near a large volume CSC may significantly improve neonatal HLHS survival.

Potential of magnetic resonance for imaging the fetal heart

Significant congenital heart disease (sCHD) affects 3.6 per 1000 births, and is often associated with extracardiac and chromosomal anomalies. Although early mortality has been substantially reduced and the rate of long-term survival has improved, sCHD is, after preterm birth, the second most frequent cause of neonatal infant death. The prenatal detection of cardiac and vascular abnormalities enables optimal parental counselling and perinatal management. Echocardiography (ECG) is the first-line examination and gold standard by which cardiac malformations are defined. However, adequate examination by an experienced healthcare provider with modern technical imaging equipment is required. In addition, maternal factors and the gestational age may lower the image quality. Fetal magnetic resonance imaging (MRI) has been implemented over the last several years and is already used in the clinical routine as a second-line approach to assess fetal abnormalities. MRI of the fetal heart is still not routinely performed. Nevertheless, fetal cardiac MRI has the potential to complement ultrasound in detecting cardiovascular malformations and extracardiac lesions. The present work reviews the potential of MRI to delineate the anatomy and pathologies of the fetal heart. This work also deals with the limitations and continuing developments designed to overcome the current problems in cardiac imaging, including fast fetal heart rates, the lack of ECG-gating, and the presence of fetal movements.

Prematurity and congenital heart disease

Significant advances in technology and therapy have led to dramatic improvements in the survival of preterm babies over the last 2 decades. Similarly, improvements in surgical and cardiac intensive care techniques have increased the feasibility of supporting even very small babies to the point of surgical repair, leading some to adopt an approach of early and complete surgical repair in preterm infants, with the aim of minimizing potential preoperative morbidity associated with extended medical management or surgical palliation. (1,2) However, multiple diagnostic and therapeutic challenges complicate the care of premature infants. Major errors in echocardiography are more common in neonates weighing less than 2.5 kg, (3) and the ideal timing and type of surgical intervention in premature infants remains unknown. These problems are compounded by the need for critical care practices that optimize management of immature cardiopulmonary, gastrointestinal, and neurological systems. This review will summarize some of the recent advances in neonatal and perinatal medicine, which have the potential to contribute to improved management of preterm infants with critical cardiac disease.

The impact of gestational age on resource utilization after open heart surgery for congenital cardiac disease from birth to 1 year of age

The impact of gestational age on perioperative morbidity was examined using a novel construct, the resource utilization index (RUI). The medical records of subjects from birth to 1 year of age entered into a pediatric cardiothoracic surgery database from a major academic medical center between 2007 and 2011 were reviewed. The hypothesis tested was that infants born at 37-38 weeks (early-term infants) experience greater resource utilization after open heart surgery than those born at 39 completed weeks and that this association can be observed until 1 year of age. The results support the premise that resource utilization increases linearly with declining gestational age among infants at 0-12 months who undergo cardiac surgery. Five of the six variables comprising the RUI showed statistically significant linear associations with gestational age in the predicted direction. Multivariate linear regression analysis showed that gestational age was a significant predictor of an increased RUI composite. Further investigation is needed to test the concept and to expand on these findings.

Pediatric postoperative cardiac care

Postoperative care of cardiac patients requires a comprehensive and multidisciplinary approach to critically ill patients with cardiac disease whose care requires a clear understanding of cardiovascular physiology. When a patient fails to progress along the projected course or decompensates acutely, prompt evaluation with bedside assessment, laboratory evaluation, and echocardiography is essential. When things do not add up, cardiac catheterization must be seriously considered. With continued advancements in the field of neonatal and pediatric postoperative cardiac care, continued improvements in overall outcomes for this specialized population are anticipated.

Outcome of fetal echocardiography: a 17 year single-institution experience in Japan

BACKGROUND

The aim of this retrospective study was to evaluate the influence of prenatal diagnosis on perinatal outcomes of congenital heart disease (CHD) over a 17 year period at a single center.

METHODS

The perinatal outcome of CHD in 146 patients diagnosed on fetal echocardiography between 1994 and 2010 were reviewed. The characteristics of 193 neonatal inpatients with CHD treated at the authors' department between 2001 and 2010 were also analyzed; among the inpatients, 61 were diagnosed before birth (prenatal group) and 132 were diagnosed after birth (postnatal group).

RESULTS

Among the 146 patients prenatally diagnosed with CHD, the prenatal mortality, including abortion and stillbirth, decreased from 1994 to 2010. Among the 193 neonatal inpatients, the prenatal group had lower gestational age and bodyweight than the postnatal group. Further, the prenatal group had lower blood pH at admission, but no patient in that group experienced ductal shock, although six patients in the postnatal group did. The average dose of prostaglandin E1 used in duct-dependent CHD was significantly lower in the prenatal group than in the postnatal group (3.4 vs. 4.6 ng/kg per min; P = 0.015).

CONCLUSIONS

Prenatal diagnosis of CHD enables planned labor, prevents ductal shock, and reduces prostaglandin E1 side-effects and medical expenditure.

Recent incidence of congenital heart disease in neonatal care unit of secondary medical center: a single center study

Purpose

With feasibility in the diagnoses of congenital heart disease (CHD) in the antenatal period, we suspect changes have occurred in its incidence. No data have been reported about the current incidence of simple forms of CHD in Korea. We have attempted to assess the recent incidence and characteristics of CHD in the neonatal care unit of a secondary referral medical center.

Methods

Medical records of 497 neonatal care unit patients who underwent echocardiography in the past 5 years were reviewed. Pre-term infants with patent ductus arteriosus and other transient, minimal lesions were excluded from this study.

Results

Although the number of inpatients remained stable, the incidence of simple forms of CHD showed a gradual decrease over the 5-year study period; a markedly low incidence of complex forms was seen as well. CHD was observed in 3.7% full-term and 6.8% pre-term infants. CHD was observed in 152 infants weighing >2,500 g (3.5% of corresponding birth weight infants); 65 weighing 1,000 to 2,500 g (9.3%); and 6 weighing <1,000 g (8.0%). The incidence of CHD was higher in the pre-term group and the low birth weight group than in each corresponding subgroup (P<0.001); however, the incidence of complex CHD in full-term neonates was high. The number of patients with extracardiac structural anomalies has also shown a gradual decrease every year for the past 5 years.

Conclusion

Findings from our study suggest that the recent incidence and disease pattern of CHD might have changed for both complex and simple forms of CHD in Korea.

Impact of prenatal diagnosis on neurocognitive outcomes in children with transposition of the great arteries

OBJECTIVES

To assess the effect of prenatal diagnosis of congenital heart disease on neurocognitive outcomes in children with d-transposition of the great arteries (TGA) after surgical correction.

STUDY DESIGN

A prospective study of children born with a TGA between 2003 and 2005 and aged 4 to 6 years was conducted. General intelligence, language, executive functions, and social cognition scores and preoperative, intraoperative, and postoperative factors were evaluated according to time of TGA diagnosis. Neurocognitive data were also compared with a control group.

RESULTS

Forty-five eligible patients (67% male) were examined; 29 had a prenatal diagnosis of TGA and 16 did not. All children were comparable in age, sex, and demographic variables. Diagnostic groups did not differ in preoperative, intraoperative, and postoperative variables. Preoperative acidosis was more frequent in the postnatal group (18% versus 3%). All patients had normal IQ scores, language, and verbal working memory. However, neurocognitive deficits were more prevalent and more severe in children with a postnatal-TGA. Prenatal diagnosis was associated with better outcomes in executive functions.

CONCLUSIONS

Prenatal diagnosis of TGA is associated with better neurocognitive outcomes. Time of diagnosis may influence the development of early complex cognitive skills such as executive functions.

Short-term neurodevelopmental outcomes in neonates with congenital heart disease: the era of newer surgical strategies

OBJECTIVE

The objective of this study was to determine neurodevelopmental outcomes up to 30 months of age in a cohort of neonates requiring surgical intervention without circulatory arrest for congenital heart disease and to correlate these outcomes with characteristics detected prior to hospital discharge.

DESIGN AND SETTING

An observational cohort of surviving neonates who underwent surgical intervention without circulatory arrest for congenital heart disease between 2002 and 2003 was studied at a single tertiary care institution.

PATIENTS

Thirty-five patients were followed from 4 to 6 months of age until 24-30 months of age.

OUTCOME MEASURES

Neuromotor abnormalities, use of special services, and degree of developmental delay at set intervals between 4 and 30 months of age were retrospectively obtained from clinical reports. The relationship between these outcomes and clinical characteristics prior to hospital discharge was analyzed.

RESULTS

Those with neuromotor abnormalities prior to discharge were likely to have persistent abnormalities in muscle strength, tone, and symmetry until 4-6 months of age, odds ratio 6 (1.3-29). By 24-30 months of age, motor abnormalities or developmental delay occurred in 10 of 20 infants (50%), but were no longer significantly associated with predischarge findings.

CONCLUSIONS

Infants undergoing surgical intervention for congenital heart disease are at risk for neurodevelopmental abnormalities, which may not become apparent until months after hospital discharge. Early impairment may also resolve over time. Close developmental follow-up in this high-risk cohort of patients is warranted.

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.

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.

Fetal and post-natal diagnosis of major congenital heart disease: implications for medical and psychological care in the current era

AIM

The fetal or post-natal diagnosis of major congenital cardiac abnormality has important medical and psychological consequences.

METHODS

We reviewed infants who underwent cardiac surgery in the first year of life at the Heart Centre for Children, The Children's Hospital at Westmead during 2009. The aims of this study were to: (i) examine the key features of cardiac diagnosis and clinical outcome, and (ii) consider how these data can inform priorities for the delivery of clinical services.

RESULTS

Over the 12-month study period, a first cardiac surgical procedure was performed on 195 infants, with 85 infants (44%) diagnosed in the antenatal period. Of the total sample, a subset of 90 babies (46%) underwent their first procedure in the neonatal period, with 62% having had a fetal diagnosis. Major intracardiac lesions including truncus arteriosus (100%), single ventricular lesions (83%), pulmonary atresia with ventricular septal defect (78%) and transposition of the great arteries (53%) were diagnosed prior to birth. Improved haemodynamic stability at initial presentation was found in those with a fetal diagnosis. The overall mortality rate for all patients was 6.1% at 12 months, with a higher mortality in infants with single ventricle.

CONCLUSIONS

The contemporary paradigm of care for infants with major congenital heart disease requires a multidisciplinary approach to care, with improvements in clinician-clinician and clinician-family communication, and psychological support and education for families. Changes in the allocation of resources are required to meet this model of best practice.

Prenatal diagnosis of hypoplastic left heart syndrome in current era

We sought to evaluate the relation of a prenatal diagnosis (preDx) with morbidity and mortality during the initial hospitalization in a contemporary cohort of patients with hypoplastic left heart syndrome (HLHS). A retrospective study of patients with HLHS presenting from 1999 to 2010 was performed. Patients with genetic disorders or a gestational age <34 weeks or who had intentionally received comfort care only were excluded. Of the 81 patients meeting the study criteria, 49 had a preDx and 32 were diagnosed postnatally (postDx). Birth weight (median 3.0 vs 3.4 kg; p = 0.007) and gestational age (median 38 vs 39 weeks; p <0.001) were lower in the preDx than in the postDx patients. Preoperatively, the postDx patients were intubated more frequently (97% vs 71%, p = 0.004) and ventilated longer (median 96 vs 24 hours, p = 0.005) than the preDx patients. They also had more preoperative acidosis, multiorgan failure, tricuspid valve regurgitation, and right ventricular dysfunction. Of the 73 patients undergoing surgery, no difference in survival was seen between the preDx and postDx groups (91% vs 89%). The median duration of postoperative ventilation was 7 days and the median length of stay was 36 days for the 66 survivors, with no difference between the 2 groups. Postoperative morbidities, including chylothorax and infection, were also similar in the preDx and postDx patients. No studied preoperative factor was associated with death, duration of postoperative ventilation, or length of stay. In conclusion, our recent experience has shown that preDx of HLHS was not associated with a survival advantage, fewer postoperative complications, or shorter length of stay. Improved preoperative status was observed in the preDx patients; however, they were born earlier with a lower birthweight. What effect these factors might have on longer term morbidity remains unknown.

Trajectories of parasympathetic nervous system function before, during, and after feeding in infants with transposition of the great arteries

BACKGROUND

Compromised parasympathetic response to stressors may underlie feeding difficulties in infants with complex congenital heart defects, but little is known about the temporal pattern of parasympathetic response across phases of feeding.

OBJECTIVES

The aim of this study was to describe initial data exploration of trajectories of parasympathetic response to feeding in 15 infants with surgically corrected transposition of the great arteries and to explore the effects of feeding method, feeding skill, and maternal sensitivity on trajectories.

METHOD

In this descriptive, exploratory study, parasympathetic function was measured using high-frequency heart rate variability (HF HRV), feeding skill was measured using the Early Feeding Skills assessment, and maternal sensitivity was measured using the Parent-Child Early Relational Assessment. Data were collected before, during, and after feeding at 2 weeks and 2 months of age. Trajectories of parasympathetic function and relationships with possible contributing factors were examined graphically.

RESULTS

Marked between-infant variability in HF HRV across phases of feeding was apparent at both ages, although it was attenuated at 2 months. Four patterns of HF HRV trajectories across phases of feeding were identified and associated with feeding method, feeding skill, and maternal sensitivity. Developmental increases in HF HRV were apparent in most breast-fed, but not bottle-fed, infants.

DISCUSSION

This exploratory data analysis provides critical information in preparation for a larger study in which varying trajectories and potential contributing factors can be modeled in relationship to infant outcomes. Findings support inclusion of feeding method, feeding skill, and maternal sensitivity in modeling parasympathetic function across feeding.