Outcomes and risk factors for mortality in premature neonates with critical congenital heart disease

Comparison of Apgar scores and cord blood gas parameters in fetuses with isolated congenital heart disease and healthy controls

OBJECTIVE

This retrospective study aimed to investigate how congenital heart disease (CHD) affects early neonatal outcomes by comparing Apgar scores and umbilical cord blood gas parameters between fetuses with structural cardiac anomalies and healthy controls. Additionally, within the CHD group, the study explored the relationship between these parameters and mortality within six months.

METHODS

Data from 68 cases of prenatally diagnosed CHD were collected from electronic medical records, excluding cases with missing data or additional comorbidities. Only patients delivered by elective cesarean section, without any attempt at labor, were analyzed to avoid potential confounding factors. A control group of 147 healthy newborns was matched for delivery route, maternal age, and gestational week. Apgar scores at 1, 5, and 10 minutes, as well as umbilical cord blood pH, base deficit, and lactate levels, were recorded.

RESULTS

Maternal age, gestational week at delivery, and birth weight were similar between the CHD and control groups. While Apgar score distribution was significantly lower at 1st, 5th, and 10th minutes in the CHD group, umbilical cord blood gas parameters did not show significant differences between groups. Within the CHD group, lower umbilical cord blood pH and larger base deficit were associated with mortality within six months.

CONCLUSION

Newborns with CHD exhibit lower Apgar scores compared to healthy controls, suggesting potential early neonatal challenges. Furthermore, umbilical cord blood pH and base deficit may serve as predictors of mortality within six months in CHD cases. Prospective studies are warranted to validate these findings and integrate them into clinical practice, acknowledging the study's retrospective design and limitations.

Morbidity and mortality in premature or low birth weight patients with congenital heart disease in three European pediatric heart centers between 2016 and 2020

Background

The treatment of preterm and low birth weight (LBW) neonates born with congenital heart disease (CHD) requiring early cardiac intervention remains challenging. We aimed to analyze morbidity and mortality in this combined high-risk patient group.

Methods

A retrospective cohort study was conducted of preterm [<37 weeks gestational age (GA)] and/or LBW neonates (<2,500 g) born with a diagnosis of CHD, which requires invasive cardiac intervention (surgery or catheter) within their first year of life. Patients born between 2016 and 2020 and treated in three European pediatric heart centers were included.

Results

A total of 308 neonates (51% male) with CHD were included. Of those, 237 (77%) were born preterm, 259 (84%) were LBW, and 188 (61%) were both. The median GA was 35.4 weeks (interquartile range 33.3-36.9) and the mean birth weight was 2,016 ± 580 g. CHD was categorized as simple (12%), moderate (64%), or severe (24%). The overall complication rate was 45% and was highest in patients with severe CHD (p = 0.002). One-year mortality (19%) was associated with severe CHD, low relative birth weight in patients with genetic diagnoses, and low GA at birth, whereas GA at birth significantly impacted survival only after 3 months of life.

Conclusions

The high morbidity and mortality in preterm and LBW neonates with CHD reflect their complexity and consequent limited treatment feasibility.

Neonatal Outcomes of Critical Congenital Heart Defects: A Multicenter Epidemiological Study of Turkish Neonatal Society : Neonatal Outcomes of CCHD

Critical congenital heart disease (CCHD) is one of the leading causes of neonatal and infant mortality. We aimed to elucidate the epidemiology, spectrum, and outcome of neonatal CCHD in Türkiye. This was a multicenter epidemiological study of neonates with CCHD conducted from October 2021 to November 2022 at national tertiary health centers. Data from 488 neonatal CCHD patients from nine centers were entered into the Trials-Network online registry system during the study period. Transposition of great arteria was the most common neonatal CHD, accounting for 19.5% of all cases. Sixty-three (12.9%) patients had extra-cardiac congenital anomalies. A total of 325 patients underwent cardiac surgery. Aortic arch repair (29.5%), arterial switch (25.5%), and modified Blalock-Taussig shunt (13.2%). Overall, in-hospital mortality was 20.1% with postoperative mortality of 19.6%. Multivariate analysis showed that the need of prostaglandin E1 before intervention, higher VIS (> 17.5), the presence of major postoperative complications, and the need for early postoperative extracorporeal membrane oxygenation were the main risk factors for mortality. The mortality rate of CCHD in our country remains high, although it varies by health center. Further research needs to be conducted to determine long-term outcomes for this vulnerable population.

Neonatal Depression Is Associated With 1-Year Mortality in Critical Congenital Heart Disease

Background Low 5-minute Apgar scores (AS) are predictive of term and preterm neonatal mortality but have not been well studied in the critical congenital heart disease (CCHD) population. We analyzed US national vital statistics data to evaluate the association between neonatal depression (AS 0-3) and 1-year mortality in CCHD. Methods and Results We performed a retrospective cohort study using 2014 to 2018 Centers for Disease Control and Prevention cohort-linked birth certificate and infant death records. Five-minute AS were categorized as ≤3, 4 to 6, or ≥7. We calculated birth rates and associated mortality rates by AS group in infants with and without CCHD. Multivariable logistic regression analyzed neonatal, maternal, and pregnancy-related risk factors for neonatal depression and 1-year mortality. Of 11 642 neonates with CCHD (0.06% of all births), the 5.8% with AS 0 to 3 accounted for 23.3% of all 1-year CCHD mortality, with 69.9% of deaths occurring within 1 month of life. Gestational age at birth, growth restriction, extracardiac defects, race, and low maternal education were associated with an increased odds of AS 0 to 3 in neonates with CCHD relative to those with AS 7 to 10 on multivariable analysis. AS 0 to 3 was associated with 1-year CCHD mortality after adjusting for these factors, prenatal care, and delivery location (adjusted odds ratio, 14.57 [95% CI, 11.73-18.10]). Conclusions The AS is a routine clinical measure providing important prognostic information in CCHD. These findings suggest that prenatal and perinatal factors, beyond those included in current risk stratification tools, are important for CCHD outcomes. Multidisciplinary collaboration to understand the pathophysiology underlying neonatal depression may help identify interventions to improve CCHD mortality rates.

Prematurity and Congenital Heart Disease: A Contemporary Review

Congenital heart disease (CHD) is the most commonly reported birth defect in newborns. Neonates with CHD are more likely to be born prematurely, and a higher proportion of preterm neonates have CHD than their term counterparts. The implications of preterm birth on the cardiac and noncardiac organ systems are vast and require special management considerations. The feasibility of surgical interventions in preterm neonates is frequently limited by patient size and delicacy of immature cardiac tissues. Thus, special care must be taken when considering the appropriate timing and type of cardiac intervention. Despite improvements in neonatal cardiac surgical outcomes, preterm and early term gestational ages and low birthweight remain important risk factors for in-hospital mortality. Understanding the risks of early delivery of neonates with prenatally diagnosed CHD may help guide perioperative management in neonates who are born preterm. In this review, we will describe the risks and benefits of early delivery, postnatal cardiac and noncardiac evaluation and management, surgical considerations, overall outcomes, and future directions regarding optimization of perinatal evaluation and management of fetuses and preterm and early term neonates with CHD.

Outcomes after neonatal cardiac surgery: The impact of a dedicated neonatal cardiac program

OBJECTIVES

Prematurity is a risk factor for in-hospital mortality after cardiac surgery. The structure of intensive care unit models designed to deliver optimal care to neonates including those born preterm with critical congenital heart disease is unknown. The objective of this study was to evaluate in-hospital outcomes after cardiac surgery across gestational ages in an institution with a dedicated neonatal cardiac program.

METHODS

This study is a single-center, retrospective review of infants who underwent cardiac surgical interventions from our dedicated neonatal cardiac intensive care program between 2006 and 2017. We evaluated in-hospital mortality and morbidity rates across all gestational ages.

RESULTS

A total of 1238 subjects met inclusion criteria over a 11-year period. Overall in-hospital mortality after cardiac surgery was 6.1%. The mortality rate in very preterm infants (n = 68; <34 weeks' gestation at birth) was 17.6% (odds ratio, 3.52 [1.4-8.53]), versus 4.3% in full-term (n = 563; 39-40 weeks) referent/control infants. Very preterm infants with isolated congenital heart disease (without evidence of other affected organ systems) experienced a mortality rate of 10.5% after cardiac surgery. Neither the late preterm (34-36 ^6/7 weeks) nor the early term (37-38 ^6/7) groups had significantly increased odds of mortality compared with full-term infants. Seventy-eight percent of very preterm infants incurred a preoperative or postoperative complication (odds ratio, 4.78 [2.61-8.97]) compared with 35% of full-term infants.

CONCLUSIONS

In this study of a single center with a dedicated neonatal cardiac program, we report some of the lowest mortality and morbidity rates after cardiac surgery in preterm infants in the recent era. The potential survival advantage of this model is most striking for very preterm infants born with isolated congenital heart disease.

Mortality and morbidity in preterm infants with congenital heart disease

AIM

To compare in-hospital mortality and rates of necrotising enterocolitis (NEC), sepsis, IVH and length of invasive respiratory support in preterm infants <36 weeks' gestation with congenital heart disease (CHD) to matched preterm infants without CHD in a single London centre over 13-year period.

METHODS

Single-centre retrospective case-control study over the 13-year period from May 2004 to May 2017.

RESULTS

Two hundred forty-seven preterm infants with CHD were matched to 494 infants without CHD. Patients with CHD had a significantly increased risk of in-hospital mortality compared to controls (OR 7.39 (95% CI 4.37-12.5); p < 0.001). Preterm infants with CHD had a higher risk of NEC (OR 2.42 (95% CI 1.32-4.45); p = 0.005), sepsis (OR 1.68 (95% CI 1.23-2.28); p = 0.001) and invasive respiratory support ≥28 days (OR 2.34 (95% CI 1.19-4.58); p = 0.017). Risk of IVH was lower in preterm infants with CHD (OR 0.22 (95% CI 0.11-0.42); p = 0.0001).

CONCLUSION

Preterm birth with CHD is associated with a higher risk of in-hospital mortality, NEC, sepsis and prolonged invasive respiratory support, but a lower risk of IVH compared to matched controls. In-hospital mortality remains high in moderate-to-late preterm infants with CHD.

The Impact of Prematurity on Morbidity and Mortality in Newborns with Dextro-transposition of the Great Arteries

Prematurity is a risk factor for adverse outcomes after arterial switch operation in newborns with D-TGA (D-TGA). In this study, we sought to investigate the impact of prematurity on postnatal and perioperative clinical management, morbidity, and mortality during hospitalization in neonates with simple and complex D-TGA who received arterial switch operation (ASO). Monocentric retrospective analysis of 100 newborns with D-TGA. Thirteen infants (13.0%) were born premature. Preterm infants required significantly more frequent mechanical ventilation in the delivery room (69.2% vs. 34.5%, p = 0.030) and during the preoperative course (76.9% vs. 37.9%, p = 0.014). Need for inotropic support (30.8% vs. 8.0%, p = 0.035) and red blood cell transfusions (46.2% vs. 10.3%, p = 0.004) was likewise increased. Preoperative mortality (23.1% vs 0.0%, p = 0.002) was significantly increased in preterm infants, with necrotizing enterocolitis as cause of death in two of three infants. In contrast, mortality during and after surgery did not differ significantly between the two groups. Cardiopulmonary bypass times were similar in both groups (median 275 vs. 263 min, p = 0.322). After ASO, arterial lactate (34.5 vs. 21.5 mg/dL, p = 0.007), duration of mechanical ventilation (median 175 vs. 106 h, p = 0.038), and venous thrombosis (40.0% vs. 4.7%, p = 0.004) were increased in preterm, as compared to term infants. Gestational age (adjusted unit odds ratio 0.383, 95% confidence interval 0.179-0.821, p = 0.014) was independently associated with mortality. Prematurity is associated with increased perioperative morbidity and increased preoperative mortality in D-TGA patients.

Monoamniotic twins pregnancy complicated by a fetal congenital heart defect – a challenge for perinatal decisions

Objectives

To analyze pregnancy management and postnatal follow-up in monochorionic monoamniotic (MCMA) pregnancies complicated by a congenital heart defect (CHD) in one twin and to compare the results with current recommendations concerning time and mode of delivery in MCMA pregnancies.

Cases presentation

Perinatal medical records of five pairs of monoamniotic twins referred to Fetal Cardiology Department were analyzed. 5 out of 23 MCMA pregnancies (21.7%) were complicated by CHD in one fetus. Cesarean section (CS) was performed between 32 and 35 weeks of gestation (WoG). 9 out of 10 neonates had respiratory failure, including all patients with CHD. Twins without congenital abnormalities spent median 21 days (range 10–40 days) in neonatal units. Patients with CHD were transferred to cardiology departments on average 6th day of life. All were operated on later than term-born neonates, 4 out of 5 required stage surgery and their median stay in the hospital was 75 days (range 48–106 days).

Conclusions

According to current recommendations, delivery in MCMA pregnancies should be scheduled at 32–34 weeks. In cases complicated by CHD in one twin, such early delivery complicates surgical treatment and may affect the final outcome. Low body weight and respiratory disorders increase the risk of complications in the perioperative period and prolong hospitalization.

New modified version of the Risk Adjustment for Congenital Heart Surgery category and mortality in premature infants with critical congenital heart disease

BACKGROUND

Despite advances in neonatal intensive care and surgical procedures, perinatal mortality rates for premature infants with congenital heart disease (CHD) remain relatively high.

PURPOSE

We aimed to describe the outcomes of premature infants with critical CHD and identify the risk factors including the new modified version of the Risk Adjustment for Congenital Heart Surgery (M-RACHS) category associated with in-hospital mortality in a Korean tertiary center.

METHODS

This was a retrospective cohort study of premature infants with critical CHD admitted to the neonatal intensive care unit from January 2005 to December 2016.

RESULTS

A total of 78 premature infants were enrolled. The median gestational age (GA) at birth was 34.9 weeks (range, 26.7-36.9 weeks), and the median birth weight was 1.91 kg (range, 0.53-4.38 kg). Surgical or percutaneous intervention was performed in 68 patients with a median GA at birth of 34.7 weeks (range, 26.7-36.8 weeks) and a median birth weight of 1.92 kg (range, 0.53-4.38 kg). The in-hospital survival rate was 76.9% among all enrolled preterm infants and 86.8% among patients who received an intervention. Very low birth weight (VLBW), persistent pulmonary hypertension of the newborn (PPHN), bronchopulmonary dysplasia (BPD), and M-RACHS category 5 or higher (more complex CHD) were independently associated with in-hospital mortality. For the 68 premature infants undergoing cardiac interventions, independent risk factors for mortality were VLBW, BPD, and CHD complexity. Late preterm infant and age at intervention were not associated with patient survival.

CONCLUSION

For premature infants with critical CHD, VLBW, PPHN, BPD, and M-RACHS category ≥5 were risk factors for mortality. A careful approach to surgical intervention and prenatal care should be taken according to CHD type and neonatal condition.

Outcomes for Ectopia Cordis

OBJECTIVES

To utilize a large multicenter neonatal cohort to describe survival and clinical outcomes of very low birth weight (VLBW) or preterm infants with ectopia cordis.

STUDY DESIGN

Data were prospectively collected on 2 211 262 infants (born 2000-2017) from 845 US centers. Both VLBW (401-1500 g or 22-29 weeks of gestation) and non-VLBW (>1500 g and >29 weeks) infants had diagnoses or anatomic descriptors consistent with ectopia cordis and/or pentalogy of Cantrell. The primary outcome was neonatal survival, defined as hospital discharge or initial length of stay of ≥12 months.

RESULTS

In total, 180 infants had ectopia cordis, 135 (76%) with findings of pentalogy of Cantrell. VLBW infants comprised 52% of the population. VLBW mortality was 96% with 79% dying within 12 hours, compared with 59% and 36%, respectively, for non-VLBW. One-third of VLBW infants received life support compared with 65% of non-VLBW. Surgery was reported for 34% of VLBW and 68% of non-VLBW infants. Congenital heart disease was reported in 8% of VLBW and 36% of non-VLBW, with conotruncal abnormalities most common. Survival exceeded 50% for infants >2500 g and >37 weeks of gestation.

CONCLUSIONS

Survival of VLBW infants with ectopia cordis was poor and substantially worse compared with non-VLBW, with notable discrepancies in resuscitative efforts and surgical interventions. Although gestational age and weight strongly influence current survival, more detailed information regarding the severity of cardiac and noncardiac abnormalities is required to fully determine prognosis and inform counseling.

Association between preoperative respiratory support and outcomes in paediatric cardiac surgery

BACKGROUND

Preoperative mechanical ventilation is associated with morbidity and mortality following CHD surgery, but prior studies lack a comprehensive analysis of how preoperative respiratory support mode and timing affects outcomes.

METHODS

We retrospectively collected data on children <18 years of age undergoing cardiac surgery at an academic tertiary care medical centre. Using multivariable regression, we examined the association between modes of preoperative respiratory support (nasal cannula, high-flow nasal cannula/noninvasive ventilation, or invasive mechanical ventilation), escalation of preoperative respiratory support, and invasive mechanical ventilation on the day of surgery for three outcomes: operative mortality, postoperative length of stay, and postoperative complications. We repeated our analysis in a subcohort of neonates.

RESULTS

A total of 701 children underwent 800 surgical procedures, and 40% received preoperative respiratory support. Among neonates, 243 patients underwent 253 surgical procedures, and 79% received preoperative respiratory support. In multivariable analysis, all modes of preoperative respiratory support, escalation in preoperative respiratory support, and invasive mechanical ventilation on the day of surgery were associated with increased odds of prolonged length of stay in children and neonates. Children (odds ratio = 3.69, 95% CI 1.2-11.4) and neonates (odds ratio = 8.97, 95% CI 1.31-61.14) on high-flow nasal cannula/noninvasive ventilation had increased odds of operative mortality compared to those on room air.

CONCLUSION

Preoperative respiratory support is associated with prolonged length of stay and mortality following CHD surgery. Knowing how preoperative respiratory support affects outcomes may help guide surgical timing, inform prognostic conversations, and improve risk stratification models.

The results of interventional catheterization in infants weighing under 2,000 g

Background

The aim of this study was to evaluate the early and mid-term results of interventional cardiac catheterization and procedure-related complications in infants weighing <2,000 g.

Methods

Between May 1998 and April 2017, 22 patients (14 males, 8 females; mean age 14±8.4 days; range, 1 to 30 days) weighing <2,000 g who underwent a total of 23 interventional cardiac catheterization were retrospectively analyzed. Procedures were balloon coarctation angioplasty in 14, balloon atrial septostomy in five, balloon aortic valvuloplasty in one, balloon pulmonary valvuloplasty in one, patent ductus arteriosus closure in one, and stent placement in the ductus in one patient. Another patient underwent balloon coarctation angioplasty and balloon aortic valvuloplasty in the same session.

Results

The overall success rate of the interventional procedures was 95.6%. The mean follow-up was 3.2±1.6 years (range, 1 to 5.5) for 18 patients with available records. The rate of serious complications was 18%. The most frequent complications in the early period were low hemoglobin levels requiring erythrocyte suspension transfusion (54.5%) and vascular injury (54.5%). Two patients required reintervention, one patient required surgery after the second intervention, and three patients required only surgery. Six patients underwent palliative interventional procedures, and interventional procedures led to definitive treatment in five patients.

Conclusion

The mortality and morbidity rate of surgery is high in premature under 2,000 g infants and interventional heart catheterization can be life-saving in this patient group, although it is associated with significant complications in low birth weight newborns.

Cardiac catheterisation in infants weighing less than 2500 grams

OBJECTIVES

The aim of the study was to report the outcome of cardiac catheterisation in low-weight patients.

BACKGROUND

Data regarding cardiac catheterisation in infants weighing &lt;2500 g are scarce.

METHODS

We reviewed all cardiac catheterisations performed in infants weighing &lt;2500 g between January 2000 and May 2016. An analysis with respect to the type of procedure, the complexity of procedure (procedure type risk), and haemodynamic vulnerability index was finally carried out. We report the occurrence of deaths and complications using the adverse event severity score.

RESULTS

A total of 218 procedures were performed on 211 patients. The mean age and weight were, respectively, 15 ± 26 days (range, 0-152) and 2111 ± 338 g (range, 1000-2500). Procedures were interventional and diagnostic, respectively, in 174 (80%) and 44 (20%) patients. Out of 218, 205 (94%) were successful. Eleven complications (5%) occurred - six with an adverse event severity score of 4 and five with an adverse event severity score of 3. Ten patients (91%) showed a favourable outcome, and one died (stent thrombosis few hours after patent ductus arteriosus stenting). No correlation was found between lower weight and occurrence of death (p = 0.68) or complications (p = 0.23). The gravity scores (procedure type risk and haemodynamic vulnerability index) were not predictive of complications.

CONCLUSIONS

Cardiac catheterisation in infants weighing &lt;2500 g appears feasible and effective with low risk. The weight should not discourage from performing cardiac catheterisation in this population.

Mortality for Critical Congenital Heart Diseases and Associated Risk Factors in Newborns. A Cohort Study

Background

Congenital heart diseases are the most common type of congenital defects, and account for more deaths in the first year of life than any other condition, when infectious etiologies are ruled out.

Objectives

To evaluate survival, and to identify risk factors in deaths in newborns with critical and/or complex congenital heart disease in the neonatal period.

Methods

A cohort study, nested to a randomized case-control, was performed, considering the Confidence Interval of 95% (95% CI) and significance level of 5%, paired by gender of the newborn and maternal age. Case-finding, interviews, medical record analysis, clinical evaluation of pulse oximetry (heart test) and Doppler echocardiogram were performed, as well as survival analysis, and identification of death-related risk factors.

Results

The risk factors found were newborns younger than 37 weeks (Relative Risk - RR: 2.89; 95% CI [1.49-5.56]; p = 0.0015), weight of less than 2,500 grams (RR: 2.33 [; 95% CI 1.26-4.29]; p = 0.0068), occurrence of twinning (RR: 11.96 [95% CI 1.43-99.85]; p = 0.022) and presence of comorbidity (RR: 2.27 [95% CI 1.58-3.26]; p < 0.0001). The incidence rate of mortality from congenital heart disease was 81 cases per 100,000 live births. The lethality attributed to critical congenital heart diseases was 64.7%, with proportional mortality of 12.0%. The survival rate at 28 days of life decreased by almost 70% in newborns with congenital heart disease. The main cause of death was cardiogenic shock.

Conclusion

Preterm infants with low birth weight and comorbidities presented a higher risk of mortality related to congenital heart diseases. This cohort was extinguished very quickly, signaling the need for greater investment in assistance technology in populations with this profile.

Surgical Interventions in Infants Born Preterm with Congenital Heart Defects: An Analysis of the Kids' Inpatient Database

OBJECTIVE

To evaluate short-term outcomes in infants born preterm with congenital heart defects (CHDs) and the factors associated with surgery, survival, and length of hospitalization in this population.

STUDY DESIGN

We analyzed data from infants born preterm (gestational age <37 weeks) enrolled in the multicenter Kids' Inpatient Database of the Healthcare Cost and Utilization Project who were admitted to the hospital within 30 days after birth. Infants with atrial septal defects were excluded.

RESULTS

Of 1 429 762 enrolled infants born preterm, 27 434 (2.0%) with CHDs were included. Overall survival to discharge was 90.5%; 74.0% among infants with critical CHDs and 45.7% among infants with hypoplastic left heart syndrome. Cardiac surgeries were performed in 12.2% of all infants born preterm. Rates of surgical intervention for infants with critical CHDs were lower for very low birth weight (≤1.5 kg) vs larger infants >1.5 kg (27% vs 44%), and only 6.3% of infants born with very low birth weight underwent surgeries in Risk-adjustment for Congenital Heart Surgery categories 4 or greater. Greater birth weight, left-sided lesions, care at children's hospitals, and absence of trisomies were associated with a greater likelihood of surgery. Birth weight <2 kg, nonwhite race, trisomy syndromes, prematurity-related morbidities, and Risk-adjustment for Congenital Heart Surgery category 4 or greater were independent predictors of mortality. Birth weight <2 kg, Risk-adjustment for Congenital Heart Surgery category, morbidities, and sidedness of lesion predicted length of stay.

CONCLUSIONS

The high survival rates of infants born preterm with CHDs suggests that a cautiously optimistic approach to surgery may be warranted in all but the most immature infants with the greatest-risk conditions.

Impact of preterm birth on infant mortality for newborns with congenital heart defects: The EPICARD population-based cohort study

Background

Congenital heart defects (CHD) and preterm birth (PTB) are major causes of infant mortality. However, limited data exist on risk of mortality associated with PTB for newborns with CHD. Our objective was to assess impact of PTB on risk of infant mortality for newborns with CHD, while taking into account the role of associated anomalies and other potentially confounding factors.

Methods

We used data on 2172 live births from a prospective population-based cohort study of CHD (the EPICARD Study) and compared neonatal, post-neonatal and overall infant mortality for infants born at <32, 32–34 and 35–36 weeks vs. those born at term (37–41 weeks).

Results

Preterm newborns had a 3.8-fold higher risk of infant death (17.9%) than term newborns (4.7%), RR 3.8, 95%CI 2.7–5.2; the risk associated with PTB was more than four-fold higher for neonatal (RR 4.3, 95% CI 2.9–6.6) and three-fold higher for post-neonatal deaths (RR 3.0, 95% CI 1.7–5.2). Survival analysis showed that newborns <35 weeks had a higher risk of mortality, which decreased but persisted after exclusion of associated anomalies and adjustment for potential confounders.

Conclusions

Preterm birth is associated with an approximately four-fold higher risk of infant mortality for newborns with CHD. This excess risk appears to be mostly limited to newborns <35 weeks of gestation and is disproportionately due to early deaths.

Congenital Heart Disease in Premature Infants 25-32 Weeks' Gestational Age

OBJECTIVE

To determine the birth prevalence of congenital heart defects (CHDs) across the spectrum of common defects in very/extremely premature infants and to compare mortality rates between premature infants with and without CHDs.

STUDY DESIGN

The Kids' Inpatient Databases (2003-2012) were used to estimate the birth prevalence of CHDs (excluding patent ductus arteriosus) in very/extremely premature infants born between 25 and 32 weeks' gestational age. Birth prevalence was compared with term infants for a subset of "severe" defects expected to be near universally diagnosed in the neonatal period. Weighted multivariable logistic regression was used to calculate aORs of mortality comparing very and extremely premature infants with vs without CHDs.

RESULTS

We identified 249 011 very/extremely premature infants, including 28 806 with CHDs. The overall birth prevalence of CHDs was 116 per 1000 very/extremely premature births. Severe CHDs had significantly higher birth prevalence in very/extremely premature infants when compared with term infants (7.4 per 1000 very/premature births vs 1.5 per 1000 term births; P < .001). Very/extremely premature infants with severe CHDs had an overall 26.3% in-hospital mortality and a 7.5-fold increased adjusted odds of death compared with those without CHDs. Mortality varied widely by defect in very/extremely premature infants, ranging from 12% for interrupted aortic arch to 67% for truncus arteriosus.

CONCLUSIONS

Given the increased birth prevalence of severe CHDs in very/extremely premature infants, and significantly higher mortality, there is justification for intensive interventions aimed at decreasing the likelihood of premature delivery for patients where CHD is diagnosed in utero.

Perinatal Decision Making for Preterm Infants with Congenital Heart Disease: Determinable Risk Factors for Mortality

For premature infants with congenital heart disease (CHD), it may be unclear when the burdens of treatment outweigh potential benefits. Parents may thus have to choose between comfort care at birth and medical stabilization until surgical repair is feasible. Better defined outcome data, including risk factors for mortality, are needed to counsel expectant parents who are considering intensive care for premature infants with CHD. We sought to evaluate outcomes in this population to inform expectant parents considering intensive versus palliative care at birth. We performed a retrospective cohort study of infants born <34 weeks who received intensive care with critical or moderately severe CHD predicted to require surgery in the neonatal period or the first 6 months of life. 46 % of 54 infants survived. Among non-survivors, 74 % died prior to surgery (median age 24 days). Of the infants that underwent surgery, 75 % survived. Survival was lower among infants <32 weeks gestational age (GA) (p = 0.013), with birth weight (BW) <1500 g (p = 0.011), or with extra-cardiac anomalies (ECA) (p = 0.015). GA and ECA remained significant risk factors for mortality in multiple logistic regression analysis. In summary, GA < 32 weeks, BW < 1500 g, and ECA are determinable prenatally and were significant risk factors for mortality. The majority of infants who survived to cardiac intervention survived neonatal hospitalization, whereas most of the infants who died did so prior to surgery. For some expectant parents, this early declaration of mortality may support a trial of intensive care while avoiding burdensome interventions.

Management of the Preterm Infant with Congenital Heart Disease

The premature neonate with congenital heart disease (CHD) represents a challenging population for clinicians and researchers. The interaction between prematurity and CHD is poorly understood; epidemiologic study suggests that premature newborns are more likely to have CHD and that fetuses with CHD are more likely to be born premature. Understanding the key physiologic features of this special patient population is paramount. Clinicians have debated optimal timing for referral for cardiac surgery, and management in the postoperative period has rapidly advanced. This article summarizes the key concepts and literature in the care of the premature neonate with CHD.

Abnormal development of thalamic microstructure in premature neonates with congenital heart disease

Preterm birth is associated with alteration in corticothalamic development, which underlies poor neurodevelopmental outcomes. Our hypothesis was that preterm neonates with CHD would demonstrate abnormal thalamic microstructure when compared to critically ill neonates without CHD. A secondary aim was to identify any association between thalamic microstructural abnormalities and perioperative clinical variables. We compared thalamic DTI measurements in 21 preterm neonates with CHD to two cohorts of neonates without CHD: 28 term and 27 preterm neonates, identified from the same neonatal intensive care unit. Comparison was made with three other selected white matter regions using ROI manual-based measurements. Correlation was made with post-conceptional age and perioperative clinical variables. In preterm neonates with CHD, there were age-related differences in thalamic diffusivity (axial and radial) compared to the preterm and term non-CHD group, in contrast to no differences in anisotropy. Contrary to our hypothesis, abnormal thalamic and optic radiation microstructure was most strongly associated with an elevated first arterial blood gas pO2 and elevated preoperative arterial blood gas pH (p < 0.05). Age-related thalamic microstructural abnormalities were observed in preterm neonates with CHD. Perinatal hyperoxemia and increased perioperative serum pH were associated with abnormal thalamic microstructure in preterm neonates with CHD. This study emphasizes the vulnerability of thalamocortical development in the preterm neonate with CHD.

Outcomes of cardiac surgery in patients weighing <2.5 kg: affect of patient-dependent and -independent variables

OBJECTIVE

A recent Society of Thoracic Surgeons database study showed that low weight (<2.5 kg) at surgery was associated with high operative mortality (16%). We sought to assess the outcomes after cardiac repair in patients weighing <2.5 kg versus 2.5 to 4.5 kg in an institution with a dedicated neonatal cardiac program and to determine the potential role played by prematurity, the Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) risk categories, uni/biventricular pathway, and surgical timing.

METHODS

We analyzed the outcomes (hospital mortality, early reintervention, postoperative length of stay, mortality [at the last follow-up point]) in patients weighing <2.5 kg at surgery (n = 146; group 1) and 2.5 to 4.5 kg (n = 622; group 2), who had undergone open or closed cardiac repairs from January 2006 to December 2012 at our institution. The statistical analysis was stratified by prematurity, STAT risk category, uni/biventricular pathway, and usual versus delayed surgical timing. Univariate versus multivariate risk analysis was performed. The mean follow-up was 21.6 ± 25.6 months.

RESULTS

Hospital mortality in group 1 was 10.9% (n = 16) versus 4.8% (n = 30) in group 2 (P = .007). The postoperative length of stay and early unplanned reintervention rate were similar between the 2 groups. Late mortality in group 1 was 0.7% (n = 1). In group 1, early outcomes were independent of the STAT risk category, uni/biventricular pathway, or surgical timing compared with group 2. A lower gestational age at birth was an independent risk factor for early mortality in group 1.

CONCLUSIONS

A dedicated multidisciplinary neonatal cardiac program can yield good outcomes for neonates and infants weighing <2.5 kg independently of the STAT risk category and uni/biventricular pathway. A lower gestational age at birth was an independent risk factor for hospital mortality.

Hybrid perventricular pulmonary valve perforation and right ventricular outflow stent placement: a case report of a premature, 1.3-kg neonate with tetralogy of Fallot and pulmonary atresia

Premature infants with very low birth weight with tetralogy of Fallot and pulmonary atresia (TOF/PA) have been shown to have poor surgical outcomes. Palliating these patients by stenting the right ventricular outflow tract (RVOT) has been shown to be safe and effective. In patients with very low birth weight, a hybrid perventricular approach offers the ability to perform pulmonary valve perforation and RVOT stent placement while avoiding cardiopulmonary bypass and femoral vessel complications in the neonatal period. We present a hybrid perventricular treatment of a patient weighing 1.3 kg with TOF/PA.

Red cell transfusion management for patients undergoing cardiac surgery for congenital heart disease

BACKGROUND

Congenital heart disease is the most commonly diagnosed neonatal congenital condition. Without surgery, only 30% to 40% of patients affected will survive to 10 years old. Mortality has fallen since the 1990s with 2006 to 2007 figures showing surgical survival at one year of 95%. Patients with congenital heart disease are potentially exposed to red cell transfusion at many points in the surgical pathway. There are a number of risks associated with red cell transfusion that may be translated into increased patient morbidity and mortality.

OBJECTIVES

To evaluate the effects of red cell transfusion on mortality and morbidity on patients with congenital heart disease at the time of cardiac surgery.

SEARCH METHODS

We searched 11 bibliographic databases and three ongoing trials databases including the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 5, 2013), MEDLINE (Ovid, 1950 to 11 June 2013), EMBASE (Ovid, 1980 to 11 June 2013), ClinicalTrials.gov, World Health Organization (WHO) ICTRP and the ISRCTN Register (to June 2013). We also searched references of all identified trials, relevant review articles and abstracts from between 2006 and 2010 of the most relevant conferences. We did not limit the searches by language of publication.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing red cell transfusion interventions in patients undergoing cardiac surgery for congenital heart disease. We included participants of any age (neonates, paediatrics and adults) and with any type of congenital heart disease (cyanotic or acyanotic). We excluded patients with congenital heart disease undergoing non-cardiac surgery. No co-morbidities were excluded.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trial quality and extracted data. We contacted study authors for additional information.

MAIN RESULTS

We identified 11 trials (862 participants). All trials were in neonatal or paediatric populations. The trials covered only three areas of interest: restrictive versus liberal transfusion triggers (two trials), leukoreduction versus non-leukoreduction (two trials) and standard versus non-standard cardiopulmonary bypass (CPB) prime (seven trials). Owing to the clinical diversity in the participant groups (cyanotic (three trials), acyanotic (four trials) or mixed (four trials)) and the intervention groups, it was not appropriate to pool data in a meta-analysis. No study reported data for all the outcomes of interest to this review. Risk of bias was mixed across the included trials, with only attrition bias being low across all trials. Blinding of study personnel and participants was not always possible, depending on the intervention being used.Five trials (628 participants) reported the primary outcome: 30-day mortality. In three trials (a trial evaluating restrictive and liberal transfusion (125 participants), a trial of cell salvage during CPB (309 participants) and a trial of washed red blood cells during CPB (128 participants)), there was no clear difference in mortality at 30 days between the intervention arms. In two trials comparing standard and non-standard CPB prime, there were no deaths in either randomised group. Long-term mortality was similar between randomised groups in one trial each comparing restrictive and liberal transfusion or standard and non-standard CPB prime.Four trials explored a range of adverse effects following red cell transfusion. Kidney failure was the only adverse event that was significantly different: patients receiving cell salvaged red blood cells during CPB were less likely to have renal failure than patients not exposed to cell salvage (risk ratio (RR) 0.26, 95% confidence interval (CI) 0.09 to 0.79, 1 study, 309 participants). There was insufficient evidence to determine whether there was a difference between transfusion strategies for any other severe adverse events.The duration of mechanical ventilation was measured in seven trials (768 participants). Overall, there was no consistent difference in the duration of mechanical ventilation between the intervention and control arms.The duration of intensive care unit (ICU) stay was measured in six trials (459 participants). There was no clear difference in the duration of ICU stay between the intervention arms in the transfusion trigger and leukoreduction trials. In the standard versus non-standard CPB prime trials, one trial examining the impact of washing transfused bypass prime red blood cells showed no clear difference in duration of ICU stay between the intervention arms, while the trial assessing ultrafiltration of the priming blood showed a shorter duration of ICU stay in the ultrafiltration group.

AUTHORS' CONCLUSIONS

There are only a small number of small and heterogeneous trials so there is insufficient evidence to assess the impact of red cell transfusion on patients with congenital heart disease undergoing cardiac surgery accurately. It is possible that the presence or absence of cyanosis impacts on trial outcomes, which would necessitate different clinical management of two groups. Further adequately powered, specific, high-quality trials are warranted to assess this fully.

Abnormal cerebral microstructure in premature neonates with congenital heart disease

BACKGROUND AND PURPOSE

Abnormal cerebral microstructure has been documented in term neonates with congenital heart disease, portending risk for injury and poor neurodevelopmental outcome. Our hypothesis was that preterm neonates with congenital heart disease would demonstrate diffuse cerebral microstructural abnormalities when compared with critically ill neonates without congenital heart disease. A secondary aim was to identify any association between microstructural abnormalities, white matter injury (eg, punctate white matter lesions), and other clinical variables, including heart lesions.

MATERIALS AND METHODS

With the use of tract-based spatial statistics, an unbiased, voxelwise method for analyzing diffusion tensor imaging data, we compared 21 preterm neonates with congenital heart disease with 2 cohorts of neonates without congenital heart disease: 28 term and 27 preterm neonates, identified from the same neonatal intensive care unit.

RESULTS

Compared with term neonates without congenital heart disease, preterm neonates with congenital heart disease had microstructural abnormalities in widespread regions of the central white matter. However, 42% of the preterm neonates with congenital heart disease had punctate white matter lesions. When neonates with punctate white matter lesions were excluded, microstructural abnormalities remained only in the splenium. Preterm neonates with congenital heart disease had similar microstructure to preterm neonates without congenital heart disease.

CONCLUSIONS

Diffuse microstructural abnormalities were observed in preterm neonates with congenital heart disease, strongly associated with punctate white matter lesions. Independently, regional vulnerability of the splenium, a structure associated with visual spatial function, was observed in all preterm neonates with congenital heart disease.

PITX2c loss-of-function mutations responsible for congenital atrial septal defects

Congenital heart disease (CHD) is the most common form of developmental anomaly and is the leading non-infectious cause of infant mortality. A growing body of evidence demonstrates that genetic risk factors are involved in the pathogenesis of CHD. However, CHD is a genetically heterogeneous disease and the genetic determinants for CHD in most patients remain unclear. In the present study, the entire coding region and splice junction sites of the PITX2c gene, which encodes a homeobox transcription factor crucial for normal cardiovascular genesis, was sequenced in 150 unrelated patients with various CHDs. The 200 unrelated control individuals were subsequently genotyped. The functional characteristics of the mutations were explored using a dual-luciferase reporter assay system. As a result, two novel heterozygous PITX2c mutations, p.H98Q and p.M119T, were identified in 2 unrelated patients with atrial septal defects, respectively. The variations were absent in 400 control chromosomes and the affected amino acids were completely conserved evolutionarily. The two variants were both predicted to be disease-causing by MutationTaster and PolyPhen-2, and the functional analysis revealed that the PITX2c mutants were consistently associated with significantly reduced transcriptional activity compared with their wild-type counterpart. These findings firstly link PITX2c loss-of-function mutations to atrial septal defects in humans, which provide novel insight into the molecular mechanism responsible for CHD, suggesting potential implications for the early prophylaxis and allele-specific treatment of CHD.

Catheterization-based intervention in low birth weight infants less than 2.5 kg with acute and long-term outcome

BACKGROUND

The number of low birth weight infants with congenital heart disease is increasing and catheterizations may have an increased risk for mortality and morbidity.

OBJECTIVES

We investigate the outcome and complications of cardiac catheterizations in infants weighing < 2.5 kg.

METHODS

Retrospective review of catheterization records from 1995 to 2010 in infants weighing < 2.5 kg. The demographics, procedure, outcome, and follow-up data were collected.

RESULTS

Of 101 catheterizations performed in 88 patients, 45 (45%) catheterizations were interventional. Balloon atrial septostomy (n = 23), pulmonary valvuloplasty (14), aortic valvuloplasty (4), stent placement (3), balloon angioplasty (2), and temporary pacemaker insertion (1) were successfully performed. Balloon atrial septostomy was performed with pulmonary or aortic valvuloplasty in two catheterizations. Infants < 2.5 kg had higher significant adverse event rate that those 2.5-3.5 kg (13% versus 6.6%, P < 0.05). No procedural death was noted. Significant adverse events (n = 13) included cardiopulmonary resuscitation three, vascular six, arrhythmia three, and apnea requiring intubation one. On median follow-up of 3 years (0.03 to 14), n = 69, mortality rate was 36%. In six patients with valvar pulmonary stenosis with median follow-up of 6 years (0.75-13), four (67%) did not require re-intervention. Of two patients with aortic stenosis, one did not require repeat intervention for 6 years (last follow-up).

CONCLUSION

Interventional catheterization is feasible with low procedural morbidity and mortality in high risk infants < 2.5 kg. Catheterization primarily serves as a palliative procedure to stabilize infants for definitive treatment. Balloon valvuloplasty may be effective for isolated valvar pulmonary stenosis in infants < 2.5 kg.

Increased morbidity and mortality in very preterm/VLBW infants with congenital heart disease

PURPOSE

To study the association between congenital heart diseases (CHD) and in-hospital mortality and morbidity of very preterm/very low birth weight (VLBW) infants.

METHODS

The area-based prospective cohort study ACTION included all infants with gestational age (GA) 22-31 weeks or birth weight <1,500 g admitted to neonatal care between July 2003 and June 2005 in six Italian regions (n = 3,684). CHD were coded according to ICD9-CM. Cluster multivariable logistic regression analyses were used to assess the relationship between CHD and mortality and selected morbidities [neonatal infection, ultrasound brain abnormalities, retinopathy of prematurity (ROP), and bronchopulmonary dysplasia (BPD)] adjusting for potential confounders.

RESULTS

Seventy-one patients had CHD [19.3 ‰, 95 % confidence interval (CI) 15.1-24.2 ‰]. The most common lesions were isolated atrial and ventricular septal defects (31.1 and 26.8 %, respectively), pulmonary valvar stenosis (12.7 %), and tetralogy of Fallot (5.6 %). Compared with other infants, CHD patients showed significantly higher GA and frequency of small for gestational age (SGA, i.e., birth weight ≤3rd centile). After adjustment for GA, sex, SGA, presence of extracardiac malformations or chromosomal anomalies, and region of birth, CHD patients had a significantly higher likelihood of infection, BPD, ROP, and, after 27 weeks gestation only, hospital mortality. The increased risk of ROP appeared to be partly due to infection.

CONCLUSIONS

In very preterm/VLBW infants CHD are more prevalent than in the general liveborn population, and confer an increased risk of death and serious morbidities independently of other risk factors. These results may be useful to better tailor prognostic assessment and diagnostic and therapeutic interventions for these children.

GATA5 loss-of-function mutation responsible for the congenital ventriculoseptal defect

The ventriculoseptal defect (VSD) is the most common form of congenital heart disease and a leading noninfectious cause of infant mortality. Growing evidence demonstrates that genetic defects are associated with congenital VSD. Nevertheless, VSD is genetically heterogeneous, and the molecular basis for VSD in an overwhelming majority of patients remains unknown. In this study, the whole coding region of GATA5, a gene encoding a zinc finger transcription factor crucial for normal cardiogenesis, was sequenced in 120 unrelated patients with VSD. The available relatives of the patient harboring the identified mutation and 200 unrelated individuals used as controls were subsequently genotyped. The causative potential of a sequence variation was evaluated by MutationTaster, and the functional effect of the mutation was characterized using a luciferase reporter assay system. As a result, a novel heterozygous GATA5 mutation, p.L199V, was identified in a patient with VSD, which was absent in 400 control chromosomes. Genetic analysis of the mutation carrier's available family members showed that the substitution co-segregated with VSD transmitted in an autosomal dominant pattern. The p.L199V variation was automatically predicted to be disease causing, and the functional analysis showed that the GATA5 p.L199V mutant protein was associated with significantly reduced transcriptional activation compared with its wild-type counterpart. To the best of the authors' knowledge, this is the first report on the link of functionally compromised GATA5 to human VSD, suggesting potential implications for the early prophylaxis and personalized treatment of VSD.

Unplanned reinterventions are associated with postoperative mortality in neonates with critical congenital heart disease

OBJECTIVE

Neonates with critical congenital heart disease remain at risk of adverse outcomes after cardiac surgery. Residual or undiagnosed anatomic lesions might be contributory. The present study aimed to describe the incidence and type of cardiac lesions that lead to early, unplanned cardiac reintervention, identify the risk factors for unplanned reintervention, and explore the associations between unplanned reinterventions and hospital mortality.

METHODS

The present single-center retrospective cohort study included 943 consecutive neonates with critical congenital heart disease who underwent cardiac surgery from 2002 to 2008. An unplanned cardiac reintervention was defined as a cardiac reoperation or interventional cardiac catheterization performed during the same hospitalization as the initial operation. Multivariate logistic regression analyses were used to identify the risk factors for unplanned cardiac reintervention and hospital mortality.

RESULTS

Of the 943 neonates, 104 (11%) underwent an unplanned cardiac reintervention. The independent predictors of unplanned reintervention included prenatal diagnosis, lower birth weight, need for mechanical ventilation before the initial cardiac operation, lower attending surgeon experience, and greater Risk Adjustment in Congenital Heart Surgery, version 1, category. Those who underwent reintervention had increased hospital mortality (n = 33/104, 32%) relative to those who did not (n = 31/839, 4%; adjusted odds ratio, 8.6; 95% confidence interval, 4.7 to 15.6; P < .001). The mortality rates among patients undergoing surgical reintervention (23/66, 35%) or transcatheter reintervention (4/16, 25%), or both (6/22, 27%) were similar (P = .66).

CONCLUSIONS

The need for unplanned cardiac reintervention in neonates with critical congenital heart disease is strongly associated with increased mortality. Early unplanned reinterventions might be an important covariate in outcomes studies and useful as a quality improvement measure.

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.

GATA5 loss-of-function mutations underlie tetralogy of fallot

Tetraology of Fallot (TOF) is the most common form of cyanotic congenital heart disease and is a major cause of significant morbidity and mortality. Emerging evidence demonstrates that genetic risk factors are involved in the pathogenesis of TOF. However, TOF is genetically heterogeneous and the genetic defects responsible for TOF remain largely unclear. In the present study, the whole coding region of the GATA5 gene, which encodes a zinc-finger transcription factor essential for cardiogenesis, was sequenced in 130 unrelated patients with TOF. The relatives of the index patients harboring the identified mutations and 200 unrelated control individuals were subsequently genotyped. The functional characteristics of the mutations were analyzed using a luciferase reporter assay system. As a result, 2 novel heterozygous GATA5 mutations, p.R187G and p.H207R, were identified in 2 families with autosomal dominantly inherited TOF, respectively. The variations were absent in 400 control alleles and the altered amino acids were completely conserved evolutionarily. Functional analysis showed that the GATA5 mutants were associated with significantly decreased transcriptional activation compared with their wild-type counterpart. To our knowledge, this is the first report on the association of GATA5 loss-of-function mutations with TOF, suggesting potential implications for the early prophylaxis and allele-specific therapy of human TOF.

Outcome of extremely preterm infants (<1,000 g) with congenital heart defects from the National Institute of Child Health and Human Development Neonatal Research Network

Little is known about the outcomes of extremely low birth weight (ELBW) preterm infants with congenital heart defects (CHDs). The aim of this study was to assess the mortality, morbidity, and early childhood outcomes of ELBW infants with isolated CHD compared with infants with no congenital defects. Participants were 401-1,000 g infants cared for at National Institute of Child Health and Human Development Neonatal Research Network centers between January 1, 1998, and December 31, 2005. Neonatal morbidities and 18-22 months' corrected age outcomes were assessed. Neurodevelopmental impairment (NDI) was defined as moderate to severe cerebral palsy, Bayley II mental or psychomotor developmental index <70, bilateral blindness, or hearing impairment requiring aids. Poisson regression models were used to estimate relative risks for outcomes while adjusting for gestational age, small-for-gestational-age status, and other variables. Of 14,457 ELBW infants, 110 (0.8 %) had isolated CHD, and 13,887 (96 %) had no major birth defect. The most common CHD were septal defects, tetralogy of Fallot, pulmonary valve stenosis, and coarctation of the aorta. Infants with CHD experienced increased mortality (48 % compared with 35 % for infants with no birth defect) and poorer growth. Surprisingly, the adjusted risks of other short-term neonatal morbidities associated with prematurity were not significantly different. Fifty-seven (52 %) infants with CHD survived to 18-22 months' corrected age, and 49 (86 %) infants completed follow-up. A higher proportion of surviving infants with CHD were impaired compared with those without birth defects (57 vs. 38 %, p = 0.004). Risk of death or NDI was greater for ELBW infants with CHD, although 20 % of infants survived without NDI.

Somatic mutations in the GATA6 gene underlie sporadic tetralogy of Fallot

Tetralogy of Fallot (TOF) is the most common cyanotic congenital heart disease associated with significant morbidity and mortality in humans. However, the molecular etiology underlying TOF in most patients remains largely unknown. In the present study, sequence analysis of the GATA6 gene was performed from fresh-frozen cardiac tissues and matched blood samples of 52 unrelated patients who underwent surgical repair of TOF. The cardiac tissues and matched blood specimens from 46 patients who underwent cardiac valve replacement due to rheumatic heart disease and blood samples from 200 healthy individuals as controls were genotyped. The functional characteristics of the mutations were assessed using a luciferase reporter assay system. Based on the results, two novel heterozygous GATA6 mutations, p.G367X and p.G394C, were identified in the cardiac tissues of 2 TOF patients, respectively. No mutations were found in the cardiac tissues from 46 patients with rheumatic heart disease and in the blood samples from the 298 participants. Functional analysis demonstrated that the GATA6 mutants were consistently associated with significantly reduced transcriptional activation compared with their wild-type counterpart. This is the first report on the link of somatic GATA6 mutation to TOF, providing novel insight into the molecular mechanism involved in TOF.

Novel GATA6 mutations associated with congenital ventricular septal defect or tetralogy of fallot

Congenital heart disease (CHD) is the most common form of developmental malformation and is the leading noninfectious cause of infant mortality. Emerging evidence indicates that genetic defects are involved in the pathogenesis of CHD. Nevertheless, CHD is genetically heterogeneous, and the molecular basis for CHD in a majority of patients remains unknown. In this study, the whole coding region of GATA6, a gene encoding a zinc-finger transcription factor crucial for normal cardiogenesis, was sequenced in 380 unrelated patients with CHD. The relatives of the index patients harboring the identified mutations and 200 unrelated control individuals were subsequently genotyped. The functional effect of the mutations was characterized using a luciferase reporter assay system. As a result, two novel heterozygous GATA6 mutations, p.D404Y and p.E460X, were identified in two families with ventricular septal defect and tetralogy of Fallot, respectively. The mutations co-segregated with CHD in the families with complete penetrance, and were absent in 400 control chromosomes. Functional analysis demonstrated that the mutated GATA6 proteins were associated with significantly decreased transactivational activity in comparison with their wild-type counterpart. These findings provide novel insight into the molecular mechanism implicated in CHD, suggesting potential implications for the early prophylaxis and personalized treatment of CHD.

A novel GATA4 loss-of-function mutation associated with congenital ventricular septal defect

Ventricular septal defect (VSD) is the most prevalent type of congenital heart disease and a major cause for the significantly increased morbidity and mortality among infants. Aggregating evidence indicates that genetic defects are involved in the pathogenesis of congenital VSD. Nevertheless, VSD is genetically heterogeneous, and the genetic determinants for VSD in the majority of patients remain to be identified. In this study, the entire coding region of GATA4, a gene encoding a zinc finger transcription factor essential for normal cardiac morphogenesis, was sequenced in 160 unrelated patients with VSD. The available relatives of the index patient harboring the identified mutation and 200 unrelated control individuals were subsequently genotyped. The disease-causing potential of a sequence alteration was evaluated by MutationTaster, and the functional effect of the mutation was characterized using a luciferase reporter assay system. As a result, a novel heterozygous GATA4 variation, p.R43W, was identified in a proband with VSD, that was absent in control subjects. Genetic analysis of the family members of the variation carrier showed that the substitution co-segregated with VSD. The p.R43W variant was predicted to be a pathogenic mutation, and the functional analysis demonstrated that the GATA4 R43W mutant protein resulted in significantly decreased transcriptional activity compared with its wild-type counterpart. The findings expand the mutational spectrum of GATA4 linked to VSD and provide more insight into the molecular mechanism of VSD.