A cohort study of neurodevelopmental outcome in children with DiGeorge syndrome following cardiac surgery

Executive functioning in preschoolers with 22q11.2 deletion syndrome and the impact of congenital heart defects

BACKGROUND

Executive functioning (EF) is an umbrella term for various cognitive functions that play a role in monitoring and planning to effectuate goal-directed behavior. The 22q11.2 deletion syndrome (22q11DS), the most common microdeletion syndrome, is associated with a multitude of both somatic and cognitive symptoms, including EF impairments in school-age and adolescence. However, results vary across different EF domains and studies with preschool children are scarce. As EF is critically associated with later psychopathology and adaptive functioning, our first aim was to study EF in preschool children with 22q11DS. Our second aim was to explore the effect of a congenital heart defects (CHD) on EF abilities, as CHD are common in 22q11DS and have been implicated in EF impairment in individuals with CHD without a syndromic origin.

METHODS

All children with 22q11DS (n = 44) and typically developing (TD) children (n = 81) were 3.0 to 6.5 years old and participated in a larger prospective study. We administered tasks measuring visual selective attention, visual working memory, and a task gauging broad EF abilities. The presence of CHD was determined by a pediatric cardiologist based on medical records.

RESULTS

Analyses showed that children with 22q11DS were outperformed by TD peers on the selective attention task and the working memory task. As many children were unable to complete the broad EF task, we did not run statistical analyses, but provide a qualitative description of the results. There were no differences in EF abilities between children with 22q11DS with and without CHDs.

CONCLUSION

To our knowledge, this is the first study measuring EF in a relatively large sample of young children with 22q11DS. Our results show that EF impairments are already present in early childhood in children with 22q11DS. In line with previous studies with older children with 22q11DS, CHDs do not appear to have an effect on EF performance. These findings might have important implications for early intervention and support the improvement of prognostic accuracy.

22q11.2 Deletion Syndrome: Impact of Genetics in the Treatment of Conotruncal Heart Defects

Congenital heart diseases represent one of the hallmarks of 22q11.2 deletion syndrome. In particular, conotruncal heart defects are the most frequent cardiac malformations and are often associated with other specific additional cardiovascular anomalies. These findings, together with extracardiac manifestations, may affect perioperative management and influence clinical and surgical outcome. Over the past decades, advances in genetic and clinical diagnosis and surgical treatment have led to increased survival of these patients and to progressive improvements in postoperative outcome. Several studies have investigated long-term follow-up and results of cardiac surgery in this syndrome. The aim of our review is to examine the current literature data regarding cardiac outcome and surgical prognosis of patients with 22q11.2 deletion syndrome. We thoroughly evaluate the most frequent conotruncal heart defects associated with this syndrome, such as tetralogy of Fallot, pulmonary atresia with major aortopulmonary collateral arteries, aortic arch interruption, and truncus arteriosus, highlighting the impact of genetic aspects, comorbidities, and anatomical features on cardiac surgical treatment.

Surgical Outcomes in Syndromic Tetralogy of Fallot: A Systematic Review and Evidence Quality Assessment

Tetralogy of Fallot (ToF) is one of the most common cyanotic congenital heart defects. We sought to summarize all available data regarding the epidemiology and perioperative outcomes of syndromic ToF patients. A PRISMA-compliant systematic literature review of PubMed and Cochrane Library was performed. Twelve original studies were included. The incidence of syndromic ToF was 15.3% (n = 549/3597). The most prevalent genetic syndromes were 22q11.2 deletion (47.8%; 95% CI 43.4-52.2) and trisomy 21 (41.9%; 95% CI 37.7-46.3). Complete surgical repair was performed in 75.2% of the patients (n = 161/214; 95% CI 69.0-80.1) and staged repair in 24.8% (n = 53/214; 95 CI 19.4-30.9). Relief of RVOT obstruction was performed with transannular patch in 64.7% (n = 79/122; 95% CI 55.9-72.7) of the patients, pulmonary valve-sparing technique in 17.2% (n = 21/122; 95% CI 11.5-24.9), and RV-PA conduit in 18.0% (n = 22/122; 95% CI 12.1-25.9). Pleural effusions were the most common postoperative complications (n = 28/549; 5.1%; 95% CI 3.5-7.3). Reoperations were performed in 4.4% (n = 24/549; 95% CI 2.9-6.4) of the patients. All-cause mortality rate was 9.8% (n = 51/521; 95% CI 7.5-12.7). Genetic syndromes are seen in approximately 15% of ToF patients. Long-term survival exceeds 90%, suggesting that surgical management should be dictated by anatomy regardless of genetics.

Congenital heart diseases and cardiovascular abnormalities in 22q11.2 deletion syndrome: From well-established knowledge to new frontiers

Congenital heart diseases (CHDs) and cardiovascular abnormalities are one of the pillars of clinical diagnosis of 22q11.2 deletion syndrome (22q11.2DS) and still represent the main cause of mortality in the affected children. In the past 30 years, much progress has been made in describing the anatomical patterns of CHD, in improving their diagnosis, medical treatment, and surgical procedures for these conditions, as well as in understanding the underlying genetic and developmental mechanisms. However, further studies are still needed to better determine the true prevalence of CHDs in 22q11.2DS, including data from prenatal studies and on the adult population, to further clarify the genetic mechanisms behind the high variability of phenotypic expression of 22q11.2DS, and to fully understand the mechanism responsible for the increased postoperative morbidity and for the premature death of these patients. Moreover, the increased life expectancy of persons with 22q11.2DS allowed the expansion of the adult population that poses new challenges for clinicians such as acquired cardiovascular problems and complexity related to multisystemic comorbidity. In this review, we provide a comprehensive review of the existing literature about 22q11.2DS in order to summarize the knowledge gained in the past years of clinical experience and research, as well as to identify the remaining gaps in comprehension of this syndrome and the possible future research directions.

Molecular screening for 22Q11.2 deletion syndrome in patients with congenital heart disease

Few studies have investigated the prevalence of 22q11.2 deletion syndrome (22q11.2DS) among patients with isolated heart defects or nonconotruncal heart defects. Polymerase chain reaction (PCR) followed by length polymorphism restriction fragment analysis (RFLP) is useful for low-cost molecular diagnosis and screening. This cross-sectional study included 392 patients with congenital heart disease, described clinical features, and performed PCR-RFLP for analysis of polymorphism in three loci with a high heterozygosity rate located in the typically deleted region of 1.5 megabases. Heterozygosity excluded 22q11.2DS. Patients with homozygosity for the three markers underwent multiplex ligation-dependent probe amplification (MLPA) and fluorescence in situ hybridization (FISH) for the final diagnosis, estimating the prevalence of 22q11.2DS. The use of PCR-RFLP excluded 22q11.2DS in 81.6 % (n = 320) of 392 patients. Of the remaining 72 patients, 65 underwent MLPA, showing 22q11.2DS in five cases (prevalence, 1.27 %). Four of these five patients underwent FISH, confirming the MLPA results. All five patients with the deletion had heart diseases commonly found with 22q11.2DS (interrupted aortic arch, persistent truncus arteriosus, tetralogy of Fallot, and ventricular septal defect plus atrial septal defect). Two patients had congenital extracardiac anomaly (one with arched palate and micrognathia and one with hypertelorism). Three patients reported recurrent respiratory infections, and one patient reported hypocalcemia. All were underweight or short in stature for their age. This study contributed to showing the prevalence of 22q11.2DS in patients with any congenital heart disease, with or without other features of the syndrome. Patients with 22q11.2DS may not have all the major features of the syndrome, and those that are found may be due to the heart defect.

Contribution of congenital heart disease to neuropsychiatric outcome in school-age children with 22q11.2 deletion syndrome

Children with 22q11.2 deletion syndrome (22q11DS) present with congenital heart disease (CHD) and high prevalence of psychiatric disorders and neurocognitive deficits. Although CHD has been implicated in neurodevelopment, its role in the neuropsychiatric outcome in 22q11DS is poorly understood. We investigated whether CHD contributes to the high prevalence of psychiatric disorders and neurocognitive impairments in 22q11DS. Fifty-four children ages 8-14 years with 22q11DS and 16 age-matched non-deleted children with CHD participated. They were assessed using semi-structured interviews and a Computerized Neurocognitive Battery. CHD status was assessed using available medical records. Prevalence of psychiatric disorders and cognitive profiles were compared among the groups. There were no significant differences between the prevalence of psychiatric disorders in the 22q11DS with and without CHD. In 22q11DS with CHD, the prevalence rates were 41% anxiety disorders, 37% ADHD and 71% psychosis spectrum. In 22q11DS without CHD, the rates were 33% anxiety disorders, 41% ADHD and 64% psychosis spectrum. In comparison, the non-deleted CHD group had lower rates of psychopathology (25% anxiety disorders, 6% ADHD, and 13% psychosis spectrum). Similarly, the 22q11DS groups, regardless of CHD status, had significantly greater neurocognitive deficits across multiple domains, compared to the CHD-only group. We conclude that CHD in this sample of children with 22q11.2DS does not have a major impact on the prevalence of psychiatric disorders and is not associated with increased neurocognitive deficits. These findings suggest that the 22q11.2 deletion status itself may confer significant neuropsychiatric vulnerability in this population.

Two-year neurodevelopmental outcomes of infants undergoing neonatal cardiac surgery for interrupted aortic arch: a descriptive analysis

OBJECTIVE

This study determined neurodevelopmental outcomes of survivors of neonatal cardiac surgery for interrupted aortic arch through an interprovincial program and explored preoperative, intraoperative, and postoperative outcome predictors.

METHODS

Children who underwent neonatal cardiac surgery for interrupted aortic arch at 6 weeks old or younger between 1996 and 2006 had a multidisciplinary neurodevelopmental assessment at 18 to 24 months old (mental and psychomotor developmental indices as mean +/- SD and delay [score <70]). Survivor outcomes were compared by univariate and multivariate analyses and compared between children with and without chromosomal abnormality.

RESULTS

Outcomes were available for all 26 survivors (mortality, 3.7%). Mental and psychomotor developmental indices were 75.8 +/- 17.1 and 72.3 +/- 16.9, respectively, with significantly lower scores for children with chromosomal abnormalities, which accounted for 29% of the variance in developmental indices. For the remaining 17 children without chromosomal abnormalities, mental and psychomotor developmental indices were 82.7 +/- 14.5 and 79.1 +/- 14.3, respectively, with deep hypothermic circulatory arrest time and Apgar score at 5 minutes contributing 46% of the variance in mental developmental index.

CONCLUSIONS

The neurodevelopmental indices of children who have undergone neonatal cardiac surgery for interrupted aortic arch are below normative values; those of children with chromosomal abnormalities are even lower. For children without a chromosomal abnormality, longer deep hypothermic circulatory arrest times and low Apgar scores predict lower mental developmental indices at 18 to 24 months of age.

Impact of pulse oximetry screening on the detection of duct dependent congenital heart disease: a Swedish prospective screening study in 39,821 newborns

OBJECTIVE

To evaluate the use of pulse oximetry to screen for early detection of life threatening congenital heart disease.

DESIGN

Prospective screening study with a new generation pulse oximeter before discharge from well baby nurseries in West Götaland. Cohort study comparing the detection rate of duct dependent circulation in West Götaland with that in other regions not using pulse oximetry screening. Deaths at home with undetected duct dependent circulation were included.

SETTING

All 5 maternity units in West Götaland and the supraregional referral centre for neonatal cardiac surgery.

PARTICIPANTS

39,821 screened babies born between 1 July 2004 and 31 March 2007. Total duct dependent circulation cohorts: West Götaland n=60, other referring regions n=100.

MAIN OUTCOME MEASURES

Sensitivity, specificity, positive and negative predictive values, and likelihood ratio for pulse oximetry screening and for neonatal physical examination alone.

RESULTS

In West Götaland 29 babies in well baby nurseries had duct dependent circulation undetected before neonatal discharge examination. In 13 cases, pulse oximetry showed oxygen saturations <or=90%, and (in accordance with protocol) clinical staff were immediately told of the results. Of the remaining 16 cases, physical examination alone detected 10 (63%). Combining physical examination with pulse oximetry screening had a sensitivity of 24/29 (82.8% (95% CI 64.2% to 95.2%)) and detected 100% of the babies with duct dependent lung circulation. Five cases were missed (all with aortic arch obstruction). False positive rate with pulse oximetry was substantially lower than that with physical examination alone (69/39 821 (0.17%) v 729/38 413 (1.90%), P<0.0001), and 31/69 of the "false positive" cases with pulse oximetry had other pathology. Thus, referral of all cases with positive oximetry results for echocardiography resulted in only 2.3 echocardiograms with normal cardiac findings for every true positive case of duct dependent circulation. In the cohort study, the risk of leaving hospital with undiagnosed duct dependent circulation was 28/100 (28%) in other referring regions versus 5/60 (8%) in West Götaland (P=0.0025, relative risk 3.36 (95% CI 1.37 to 8.24)). In the other referring regions 11/25 (44%) of babies with transposition of the great arteries left hospital undiagnosed versus 0/18 in West Götaland (P=0.0010), and severe acidosis at diagnosis was more common (33/100 (33%) v 7/60 (12%), P=0.0025, relative risk 2.8 (1.3 to 6.0)). Excluding premature babies and Norwood surgery, babies discharged without diagnosis had higher mortality than those diagnosed in hospital (4/27 (18%) v 1/110 (0.9%), P=0.0054). No baby died from undiagnosed duct dependent circulation in West Götaland versus five babies from the other referring regions.

CONCLUSION

Introducing pulse oximetry screening before discharge improved total detection rate of duct dependent circulation to 92%. Such screening seems cost neutral in the short term, but the probable prevention of neurological morbidity and reduced need for preoperative neonatal intensive care suggest that such screening will be cost effective long term.

Cardiac defects and results of cardiac surgery in 22q11.2 deletion syndrome

Specific types and subtypes of cardiac defects have been described in children with 22q11.2 deletion syndrome as well as in other genetic syndromes. The conotruncal heart defects occurring in patients with 22q11.2 deletion syndrome include tetralogy of Fallot, pulmonary atresia with ventricular septal defect, truncus arteriosus, interrupted aortic arch, isolated anomalies of the aortic arch, and ventricular septal defect. These conotruncal heart defects are frequently associated in this syndrome with additional cardiovascular anomalies of the aortic arch, pulmonary arteries, infundibular septum, and semilunar valves complicating cardiac anatomy and surgical treatment. In this review we describe the surgical anatomy, the operative treatment, and the prognostic results of the cardiac defects associated with 22q11.2 deletion syndrome. According to the current literature, in patients with tetralogy of Fallot with/without pulmonary atresia and truncus arteriosus, in spite of the complex cardiac anatomy, the presence of 22q11.2 deletion syndrome does not worsen the surgical prognosis. On the contrary in children with pulmonary atresia with ventricular septal defect and probably in those with interrupted aortic arch the association with 22q11.2 deletion syndrome is probably a risk factor for the operative treatment. The complex cardiovascular anatomy in association with depressed immunological status, pulmonary vascular reactivity, neonatal hypocalcemia, bronchomalacia and broncospasm, laryngeal web, and tendency to airway bleeding must be considered at the time of diagnosis and surgical procedure. Specific diagnostic, surgical, and perioperative protocols should be applied in order to provide appropriate treatment and to reduce surgical mortality and morbidity.

The fate of children with microdeletion 22q11.2 syndrome and congenital heart defect: clinical course and cardiac outcome

BACKGROUND

This study aimed to evaluate the cardiac outcome for children with microdeletion 22q11.2 and congenital heart defect (CHD).

METHODS

A total of 49 consecutive children with 22q11.2 and CHD were retrospectively identified. The CHD consisted of tetralogy of Fallot and variances (n = 22), interrupted aortic arch (n = 10), ventricular septal defect (n = 8), truncus arteriosus (n = 6), and double aortic arch (n = 1). Extracardiac anomalies were present in 46 of 47 children.

RESULTS

The median follow-up time was 8.5 years (range, 3 months to 23.5 years). Cardiac surgical repair was performed for 35 children, whereas 5 had palliative surgery, and 9 never underwent cardiac surgery. The median age at repair was 7.5 months (range, 2 days to 5 years). The mean hospital stay was 35 days (range, 7-204 days), and the intensive care unit stay was 15 days (range, 3-194 days). Significant postoperative complications occurred for 26 children (74%), and surgery for extracardiac malformations was required for 21 patients (43%). The overall mortality rate was 22% (11/49), with 1-year survival for 86% and 5-year survival for 80% of the patients. A total of 27 cardiac reinterventions were performed for 16 patients (46%) including 15 reoperations and 12 interventional catheterizations. Residual cardiac findings were present in 25 patients (71%) at the end of the follow-up period.

CONCLUSIONS

Children with microdeletion 22q11.2 and CHD are at high risk for mortality and morbidity, as determined by both the severity of the cardiac lesions and the extracardiac anomalies associated with the microdeletion.

Neurocognitive, functional, and health outcomes at 5 years of age for children after complex cardiac surgery at 6 weeks of age or younger

OBJECTIVE

This work provides neurocognitive, functional, and health outcomes for 5-year survivors of early infant complex cardiac surgery, including those with chromosomal abnormalities.

PATIENTS AND METHODS

Of 85 children (22.4% mortality), 61 received multidisciplinary, individual evaluation and parental questionnaires at 5 years. Full-scale, verbal, and performance IQ scores were compared by using analysis of variance among children who received different surgeries (arterial switch, 20; Norwood for hypoplastic left heart syndrome, 14; simple total anomalous pulmonary venous connection, 6; miscellaneous, 21; and chromosomal abnormalities, 8). Predictions from mental scores at 2 years for IQ scores at 5 years were determined.

RESULTS

Children with chromosomal abnormalities had lower full-scale and verbal IQs at 5 years than other survivors, with no differences found among the remaining groups. For children post-Norwood, performance IQ scores remained lower than for children after the arterial-switch operation. Prediction of full-scale IQ (<70) from 2-year mental scores for all 61 children were as follows: sensitivity, 87.5%; specificity, 88.1%; positive predictive value, 53.8%; and negative predictive value, 97.9%. For full-scale IQ of <85, predictions were 90.0%, 87.8%, 78.3%, and 94.7%, respectively. For those 53 without chromosomal abnormalities, full-scale IQ <70, respective predictions were 86.7%, 90.0%, 28.6%, and 97.8%, and for full-scale IQ <85, respective predictions were 85.7%, 89.7%, 75.0%, and 94.6%. Parental report indicated good health in 80% and adequate function in 67% to 88% of the children, although health-utilization numbers suggest that these reports are optimistic.

CONCLUSIONS

Five-year full-scale and verbal IQs were similar among groups, excluding those with chromosomal abnormalities. Children with chromosomal abnormalities had the lowest scores. Excluding those with chromosomal abnormalities, the mean mental scores for the children as a group tended to increase from 2 to 5 years of age, with an overall high percentage of correct classifications at 2 years.

Two-year general and neurodevelopmental outcome after neonatal complex cardiac surgery in patients with deletion 22q11.2: A comparative study

OBJECTIVE

Neonatal complex cardiac surgery carries a significant risk for adverse neurodevelopmental outcome. We hypothesized this risk to be higher in patients with deletion 22q11.2.

METHODS

From 1996 to 2004, neonates who had complex cardiac surgery at age 6 weeks or less had multisite, multidisciplinary health and neurodevelopmental outcomes (Bayley Scales of Infant Development II; mental and psychomotor developmental indices [MDI, PDI] as mean [SD] and delay [<70]) assessed at 18 to 24 months of age. All 16 patients with deletion 22q11.2 (group 1) were compared with 16 patients without deletion 22q11.2 (group 2) having undergone neonatal complex cardiac surgery at the same center and matched for cardiac lesion, socioeconomic status, and year of operation. Outcomes were compared by univariate and multivariate analyses.

RESULTS

Heart lesions in each group consisted of 6 (37.5%) cases of interrupted aortic arch, 6 (37.5%) cases of truncus arteriosus, and 4 (25%) cases of tetralogy of Fallot. Outcomes were available for all survivors. Mortality was 3 (19%) and 1 (6%) in groups 1 and 2, respectively (P = .6). MDI and PDI scores were 66.1 (10.6) and 55.0 (9.4) for group 1 and 86.3 (14.6) and 82.3 (14.3) for group 2 (P < .001). Only deletion 22q11.2 was significant in stepwise multiple regression to predict MDI and PDI scores. Mental delay occurred in 8 (61.5%) of 13 in group 1 and 2 (13.8%) of 15 in group 2 (P = .016). Psychomotor delay occurred in 11 (84.6%) of 13 in group 1 and 1 (6.7%) of 15 in group 2 (P < .001).

CONCLUSION

Neonates affected by deletion 22q11.2 and having neonatal complex cardiac surgery have significantly worse neurodevelopmental outcome than do those without deletion 22q11.2.

Neurocognitive profile in 22q11 deletion syndrome and schizophrenia

OBJECTIVE

Schizophrenia is associated with neurocognitive deficits, but its etiologic heterogeneity may complicate the delineation of a neurocognitive profile. Schizophrenia associated with 22q11 Deletion Syndrome (22qDS) represents a more genetically homogeneous subtype for study. We hypothesized that in adults with 22qDS the neurocognitive profiles would differ between those with and without schizophrenia.

METHOD

Using a comprehensive battery of tests, we compared the neurocognitive performance profiles in those with schizophrenia (n=27; 14 M, 13 F; mean age=30.6 years, SD=7.7 years) and those with no history of psychosis (n=29; 16 M, 13 F; mean age=25.0 years, SD=9.0 years).

RESULTS

The 22qDS groups with and without schizophrenia had similar mean estimated IQ (71.6, SD=8.2 and 74.8, SD=6.1, respectively) and academic achievement, however the neurocognitive profiles of the two groups differed significantly on multivariate analysis (F(24,31)=2.25, p=0.017). The group with schizophrenia performed significantly more poorly on tests of motor skills, verbal learning, and social cognition (effect sizes>or=0.8) after correction for multiple comparisons. Other tests, but not the attentional measures used, showed nominally significant differences.

CONCLUSIONS

In adults with 22qDS, the pattern of neurocognitive differences between those with and without schizophrenia appears similar to that between patients with schizophrenia and controls. Attentional dysfunction may be a more general feature of 22qDS. The findings support 22qDS-schizophrenia as a genetic model for neurodevelopmental investigations of schizophrenia.

The clinical, immunological, and molecular spectrum of chromosome 22q11.2 deletion syndrome and DiGeorge syndrome

PURPOSE OF REVIEW

New findings regarding the clinical manifestations and care of patients with DiGeorge syndrome or chromosome 22q11.2 deletion syndrome will be reviewed. Immunologists and primary care providers often are in a position to coordinate the complex care needs of these patients and an awareness of the clinical features is essential.

RECENT FINDINGS

DiGeorge syndrome typically occurs in association with a hemizygous deletion of chromosome 22q11.2. Approximately 5-10% of patients with the clinical entity of DiGeorge syndrome do not have the deletion. Recent evidence indicates that the T cell compartment in both patients with the deletion and patients with clinical DiGeorge syndrome without the deletion is less robust than is often indicated by standard T cell enumeration.

SUMMARY

This past year has seen a dramatic increase in our understanding of the clinical features of patients with the deletion. Advances in our understanding of the immunodeficiency have been particularly exciting and clinicians should be aware of the characteristics of the immunodeficiency and its changes with age.

Outcomes from an interprovincial program of newborn open heart surgery

OBJECTIVES

To determine 18-month neurodevelopmental outcome of survivors of complex open heart surgery at </=6 weeks of age through an interprovincial program and to explore preoperative, operative, and postoperative outcome predictors. Study design Of 85 children from this inception cohort (21% mortality), 67 18-month-old survivors received multidisciplinary assessment including the Bayley Scales of Infant Development-II. Cumulative risk for adverse outcome was determined through univariate and multivariate analyses.

RESULTS

Survival of the 85 children included 23 of 23 after arterial switch, 16 of 26 after Norwood, six of six after total anomalous pulmonary venous drainage repair, and 22 of 30 after miscellaneous repair. Outcomes were as follows: in-hospital death, 14 (16%); postdischarge death, four (5%); motor/sensory disability, three (4%); motor/mental delay (<70), 21 (25%); and intact survivors, 43 (50%). Cohort mental (84+/-17) and motor (80+/-22) scores were lower for those with chromosomal abnormalities, 67+/-16 and 61+/-17, respectively. Fifty-five percent of the outcome variance was explained by duration of preoperative ventilation, 18%; genetic anomaly, 5%; intraoperative variables, 18%; and postoperative variables, 14%.

CONCLUSIONS

Risk for adverse outcome is cumulative, with preoperative determinants contributing significantly to total variance. Potentially modifiable variables should be sought in an attempt to improve outcome.