Perioperative Management of Patients With DiGeorge Syndrome Undergoing Cardiac Surgery

Understanding the Variability of 22q11.2 Deletion Syndrome: The Role of Epigenetic Factors

Initially described as a triad of immunodeficiency, congenital heart defects and hypoparathyroidism, 22q11.2 deletion syndrome (22q11.2DS) now encompasses a great amount of abnormalities involving different systems. Approximately 85% of patients share a 3 Mb 22q11.2 region of hemizygous deletion in which 46 protein-coding genes are included. However, the hemizygosity of the genes of this region cannot fully explain the clinical phenotype and the phenotypic variability observed among patients. Additional mutations in genes located outside the deleted region, leading to "dual diagnosis", have been described in 1% of patients. In some cases, the hemizygosity of the 22q11.2 region unmasks autosomal recessive conditions due to additional mutations on the non-deleted allele. Some of the deleted genes play a crucial role in gene expression regulation pathways, involving the whole genome. Typical miRNA expression patterns have been identified in 22q11.2DS, due to an alteration in miRNA biogenesis, affecting the expression of several target genes. Also, a methylation epi-signature in CpG islands differentiating patients from controls has been defined. Herein, we summarize the evidence on the genetic and epigenetic mechanisms implicated in the pathogenesis of the clinical manifestations of 22q11.2 DS. The review of the literature confirms the hypothesis that the 22q11.2DS phenotype results from a network of interactions between deleted protein-coding genes and altered epigenetic regulation.

The Outcomes of Cardiac Surgery in Children With DiGeorge Syndrome in a Single Center Experience: A Retrospective Cohort Study

Background DiGeorge syndrome, a common genetic microdeletion syndrome, is associated with multiple congenital anomalies, including congenital cardiac diseases. This study aims to identify the short and midterm outcomes of cardiac surgery performed on children with DiGeorge syndrome. Methods A retrospective cohort study was conducted between the period of 2018-2022, which included children divided into two groups with a 1:2 ratio. Group one included DiGeorge syndrome patients who were diagnosed using fluorescence in situ hybridization (FISH). Group two included the control group of patients who were clear of genetic syndromes. The two groups were matched based on similar cardiac surgery, age of surgery, and Risk Adjustment in Congenital Heart Surgery (RACHS-1) score. The two groups were compared based on the demographical data and postoperative complications. Results The study consisted of 81 children; 27 were DiGeorge syndrome patients, and 54 were in the control group. DiGeorge syndrome patients showed an increase in mechanical ventilation duration (p=0.0047), intensive care unit (ICU) length of stay (p=0.0012), and hospital length of stay (p=0.0391). Moreover, they showed an increased risk for bacteremia (p=0.0414), ventilator-associated pneumonia (VAP; p=0.0036), urinary tract infections (UTI; p=0.0064), and surgical site infection (SSI; p≤0.0001). They were also more susceptible to postoperative seizures (p=0.0049). Furthermore, patients with DiGeorge syndrome had a higher prevalence of congenital renal anomalies. However, there was no mortality in either group.  Conclusion This study shows a variability in the postoperative outcomes between the two groups. The study demonstrates that patients with DiGeorge syndrome have higher risks of infections and longer hospital stay during the postoperative period. Further research with a larger sample is needed to confirm our findings.

Perinatal Diagnosis and Management of a Case with Interrupted Aortic Arch, Pulmonary Valve Dysplasia and 22q11.2 Deletion: A Case Report

The 22q11.2 deletion syndrome (22q11.2DS) is the most common chromosomal microdeletion disorder caused by hemizygous microdeletion of the long arm of chromosome 22. It is now known to have a heterogenous presentation that includes multiple additional congenital anomalies and later-onset conditions, such as gastrointestinal and renal abnormalities, autoimmune disease, variable cognitive delays, behavioral phenotypes and psychiatric illness. The purpose of our paper is to present the case of a fetus diagnosed with a complex association of cardiac anomalies: interrupted aortic arch type B, large malalignment-type ventricular septal defect, pulmonary valve dysplasia, and aberrant right subclavian artery for whom the result of genetic testing revealed 22q11.2 deletion. The pregnancy was regularly followed until delivery which took place in Germany so that neonatal cardiac surgery could be performed in an experienced center for cardiac malformations. The distinctivness of our report resides in the fact that it offers a complete image of a case of 22q11.2 deletion syndrome starting from the prenatal diagnosis (and emphasizing on the most relevant sonographic features) and, with parents not opting for termination of pregnancy, ending with the newborn surviving major cardiac surgery, offering thus the possibility to bring into focus postnatal outcome and future expectations in similar cases.

Updated clinical practice recommendations for managing children with 22q11.2 deletion syndrome

This review aimed to update the clinical practice guidelines for managing children and adolescents with 22q11.2 deletion syndrome (22q11.2DS). The 22q11.2 Society, the international scientific organization studying chromosome 22q11.2 differences and related conditions, recruited expert clinicians worldwide to revise the original 2011 pediatric clinical practice guidelines in a stepwise process: (1) a systematic literature search (1992-2021), (2) study selection and data extraction by clinical experts from 9 different countries, covering 24 subspecialties, and (3) creation of a draft consensus document based on the literature and expert opinion, which was further shaped by survey results from family support organizations regarding perceived needs. Of 2441 22q11.2DS-relevant publications initially identified, 2344 received full-text reviews, including 1545 meeting criteria for potential relevance to clinical care of children and adolescents. Informed by the available literature, recommendations were formulated. Given evidence base limitations, multidisciplinary recommendations represent consensus statements of good practice for this evolving field. These recommendations provide contemporary guidance for evaluation, surveillance, and management of the many 22q11.2DS-associated physical, cognitive, behavioral, and psychiatric morbidities while addressing important genetic counseling and psychosocial issues.

Postoperative Hypocalcemia following Non-Cardiac Surgical Procedures in Children with 22q11.2 Deletion Syndrome

The guidelines for management of children with 22q11.2 deletion syndrome (22q11DS) highlight the risk for developing hypocalcemia after surgery and recommend monitoring calcium perioperatively. Despite this guidance, little has been published on postoperative hypocalcemia and 22q11DS. Our goals were to evaluate the frequency of perioperative calcium monitoring and examine how often postoperative hypocalcemia was identified. This is a retrospective chart review of patients in our 22q Center’s repository. Inclusion criteria were a diagnosis of 22q11DS and a history of a non-cardiac surgical procedure. Data collected included all non-cardiac surgeries and perioperative calcium labs. In total, 68 patients were included and underwent 305 on-cardiac surgeries. Patients in only 17% of these surgeries had postoperative calcium testing, but of those tested, 58% showed hypocalcemia. Patients with history of hypocalcemia at the time of chart review undergoing non-cardiac surgeries were tested postoperatively 40% of the time; however, 67% of these had hypocalcemia. Similarly, for patients without history of hypocalcemia, postoperative testing occurred 60% of the time, with 52% of these having hypocalcemia. This study demonstrates that postoperative hypocalcemia in children with 22q11DS following non-cardiac surgeries is common and affects patients both with and without prior history of hypocalcemia. These data support establishing a protocol for perioperative testing/management of hypocalcemia for patients with 22q11DS.

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.

Array comparative genomic hybridisation results of non-syndromic children with the conotruncal heart anomaly

The study aimed to show the chromosomal copy number variations responsible for the aetiology in patients with isolated conotruncal heart anomaly by array comparative genomic hybridisation and identify candidate genes causing conotruncal heart disease. A total of 37 patients, 17 male, and 20 female, with isolated conotruncal heart anomalies, were included in the study. No findings indicated any syndrome in terms of dysmorphology in the patients.

RESULTS

Copy number variations were detected in the array comparative genomic hybridisation analysis of five (13.5%) of 37 patients included in the study. Three candidate genes (PRDM16, HIST1H1E, GJA5) found in these deletion and duplication regions may be associated with the conotruncal cardiac anomaly.

CONCLUSION

CHDs can be encountered as the first and sometimes the single finding of many genetic disorders in children. It is thought that genetic tests, especially array comparative genomic hybridisation, may be beneficial for children with CHD since the diagnosis of genetic diseases in these patients as early as possible will help to prevent or reduce complications that may develop in the future. Also, it would be possible to detect candidate genes responsible for conotruncal cardiac anomalies with array comparative genomic hybridisation.

Thrombocytopenia: Perioperative Considerations for Patients Undergoing Cardiac Surgery

The etiologies of thrombocytopenia in patients presenting for cardiac surgery are extensive, but clinically relevant conditions generally can be categorized by those related to decreased platelet production or increased platelet destruction. Many causes require mere acknowledgment and availability of allogeneic platelet transfusion; others have unique considerations for which providers should be familiar. The purpose of this review is to provide an overview of the common causes of thrombocytopenia, summarize the literature, and discuss perioperative considerations for patients undergoing cardiac surgery.

DiGeorge syndrome and anomalous right aortic arch with arch-on-arch and figure-of-eight configurations: Aortic sac maldevelopment and left brachiocephalic artery abnormal remodeling

We report a 6-month-old female infant with deletion of chromosome 22q11.2 (DiGeorge/VFS TUPLE 1), normal atrial arrangement with concordant atrioventricular connection, pulmonary atresia, large subaortic ventricular septal defect, diminutive native pulmonary arteries, a characteristic weird-shape right aortic arch with arch-on-arch appearance and figure of 8 configuration. We presented the cardiac computed tomographic angiographic and cardiac angiographic features. Using Autodesk 3ds Max 2018 software, we explained and illustrated the speculative embryologic etiology of this bizarre aortic archanomaly with the extensive abnormal remodeling of the left brachiocephalic artery, based on a “five-embryonic aortic arches” concept. As to the best of the authors' knowledge, this is the first report of a genetically confirmed case of DiGeorge syndrome and an exceedingly rare type of right aortic arch anomaly with embryologic explanation according to the “five-embryonic-aortic-arches” concept. It seems that the constellation of pulmonary atresia, bizarreshaped right aortic arch due to abnormal development of the aortic sac, and abnormal remodeling of the left brachiocephalic artery may be strongly suggestive of DiGeorge syndrome.

Magnetic resonance angiography (MRA) in preoperative planning for patients with 22q11.2 deletion syndrome undergoing craniofacial and otorhinolaryngologic procedures

INTRODUCTION

Patients with 22q11.2 deletion syndrome (22q11.2DS) have a variety of anatomic anomalies. For surgeons operating in proximity to the retropharynx, the most pertinent is medial displacement of the internal carotid arteries. The purpose of this study is to describe the preoperative use of magnetic resonance angiography (MRA) in surgical planning and update the incidence rate of medial carotid displacement in patients with 22q11.2DS.

METHODS

This is a retrospective cohort study of patients with a confirmed diagnosis of 22q11.2 deletion and preoperative MRA <18 years old who underwent tonsillectomy, adenoidectomy, Furlow palatoplasty (FPP), posterior pharyngeal flap (PPF), sphincter pharyngoplasty (SPP), or submucosal cleft palate (SMCP) repair between January 1st, 2008 and December 31st, 2019.

RESULTS

Ninety patients who met the inclusion criteria underwent 133 procedures. The majority identified as Caucasian (84.4%); 52.2% were female. Cervical MRA was more likely to be ordered before a PPF (80.9%) and tonsillectomy (72.7%) over a FPP (47.6%) or adenoidectomy (11.1%). Carotid medialization was visualized in 23 patients (25.6%) and was mild in 11 cases, moderate in 7 cases, and significant in 5 cases. There was no association between sex, race/ethnicity, or genetic diagnosis with carotid medialization. Flap shortening was necessary in 20% of PPF cases to avoid injuring the medialized vessel.

CONCLUSION

Patients with 22q11.2DS may have higher rates of medialization of the carotid arteries than previously thought. Given the risk for complications in these patients during pharyngeal operations, there may be a critical place for MRA in surgical planning for patients with 22q11.2DS.

Anesthetic management in tetralogy of fallot with pulmonary atresia and major aortopulmonary collateral arteries in pediatric patients: One year experience

Background:

Unlike the typical tetralogy of fallot (TOF), the presence of pulmonary atresia and major aortopulmonary collaterals is recognized as a rare but severe variant of TOF. The objective was to describe the perioperative anesthetic management of pediatric patients who underwent unifocalization procedure and to describe their postoperative morbidity and mortality.

Methods:

A retrospective observational study was conducted among pediatric patients who underwent unifocalization procedure at Prince Sultan Cardiac Center (PSCC) between October 2017 and October 2018. Unifocalization procedures were performed in a two-staged approach. Anesthetic management of both stages had similar concerns and challenges but with few peculiar issues. These included preoperative assessment, intraoperative management, vascular access, positioning, ventilation, optimizing hemodynamics, cardiopulmonary bypass monitoring, and postoperative management.

Results:

A total of 19 unifocalization procedures were included. The average age was one year and 52.6% were females. Two patients (10.5%) arrived in theater already with intubated ventilation. Continuous mandatory ventilation was used in 11 (57.9%) patients while one-lung ventilation was used in the rest of patients. Approximately, 30% of patients encountered a stormy postoperative course, 52.6% underwent cardiopulmonary bypass with or without cross-clamping of the aorta, and 10.5% had reperfusion injury.

Conclusions:

Despite the major challenges of unifocalization, significantly low rates of morbidity and mortality were observed in our patients. A thorough familiarity of different airway and ventilation issues, besides meticulous hemodynamic and anesthetic management, is of paramount importance. The maintenance of hemodynamic stability, hemostasis, and proper ventilation is critical for the success of the operation.

Emergent Transcatheter Aortic Valve Replacement (TAVR) Performed on Patient With DiGeorge Syndrome

Emergent Transcatheter Aortic Valve Replacement (TAVR) is a strategy that has been used for management of severely decompensated patients who are unlikely to tolerate an open procedure (Kolte et al., 2018). Recently, in the context of degenerated valve bioprosthesis, valve-in-valve (ViV) transcatheter aortic valve replacement has become an acceptable management strategy (Kalra et al., 2019 [2]). Here, we present this rare case of a 25-year-old, post-partum female with DiGeorge Syndrome, who presented with severe bioprosthetic valve stenosis leading to heart failure. She initially had received a biologic valve in order to have children; however, following delivery of her child, she developed valve failure that was severe enough to preclude her from receiving a surgical aortic valve replacement. ViV TAVR was performed emergently to improve heart failure and bridge the time to definitive treatment, when she would be able to safely receive a mechanical valve. After valve placement, echocardiogram showed no evidence of aortic regurgitation or paravalvular leak with a mean gradient of 2 mmHg, and she was ultimately discharged. Our patient was recovering well at her two-month follow up appointment. This case highlights the need for further research in the use of ViV TAVR in younger patient populations in emergent situations.

Evaluation of general anesthesia and sedation during dental treatment in patients with special needs: A retrospective study

Background

Patients with special health care needs are more likely to develop health problems, including dental problems. Dental treatments require a good level of communication with the patient. Therefore, in these patients, sedation and general anesthesia are an extremely humanistic approach for comfortable and successful treatment. In patients with special needs, there is no standard anesthetic approach due to varying clinical conditions. The aim of this study was to provide literature content about the anesthetic approaches used by us in patients with special needs.

Methods

The medical records of 710 patients with special health care needs treated under general anesthesia or sedation were reviewed retrospectively. Demographic data, the American Society of Anesthesiologists classification, Mallampati score, anesthesia duration, anesthesia type, anesthetic and analgesic agents used, dental treatment performed, secondary diseases, and complications in the perioperative period were recorded. Patients were evaluated under five groups: Down syndrome, other syndromes, psychiatric disorders, physical disabilities, and complicated medical story.

Results

Among the patients evaluated, 47.5% were females and 52.5% were males (mean age 15.76 ± 11.17 years), and general anesthesia and sedation were administered in 72.9% and 22.1% patients, respectively. The mean duration of anesthesia was 43.20 ± 35.85 min. Simple dental treatments were performed in all groups, and the most common complications were observed in the other syndromes group.

Conclusion

Complications can be reduced by utilizing the appropriate anesthetic approach and taking serious precautions in patients with special needs.

Early Outcomes of Cardiac Surgery in Patients with Noonan Syndrome

There is a paucity of cardiac surgery outcomes data for patients with Noonan syndrome (NS). Our objective was to evaluate early results in these patients. Between January 1999 and December 2015, 29 patients (18 males, 62%) with NS underwent cardiac surgery at our institution. Mean age was 23 ± 17.9 years; 12 (41%) were under 18 years of age. Fourteen patients (48%) had prior sternotomies. The primary operations for the main diagnosis were pulmonary valve/conduit replacement/repair (n = 14, 48%), septal myectomy for obstructive hypertrophic cardiomyopathy (n = 7, 24%), aortic valve replacement/repair (n = 4, 14%), atrial septal defect (ASD) repair (n = 2, 7%), and cardiac transplantation (n = 2, 7%). Concomitant procedures were performed in 24 patients (83%), most commonly right ventricular outflow tract reconstruction (n = 13, 45%), mitral valve repair/replacement (n = 7, 24%), and ASD repair (n = 6, 21%). Mean bypass and cross-clamp times were 88.8 ± 51 minutes and 54.7 ± 67 minutes, respectively. There was 1 early death (3%). Postoperative morbidity occurred in 18 patients (62%), most commonly arrhythmias (n = 14, 48%) or respiratory insufficiency/pneumonia (n = 6, 21%). There were 2 early reoperations and 4 early readmissions. Univariate factors associated with morbidity included male gender (P = 0.03) and longer cross-clamp time (P = 0.02). Median length of hospital stay was 6 days (interquartile range 5-10.5 days). Patients with NS frequently have multiple cardiac lesions requiring a broad spectrum of operations. Early mortality is low despite procedure complexity. Although early postoperative morbidity is common, patients overall do well with reasonable hospital lengths of stay. Additional studies are needed to evaluate long-term outcomes and quality of life.

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.

Anesthetic Management During Surgery for Tetralogy of Fallot With Pulmonary Atresia and Major Aortopulmonary Collateral Arteries

Tetralogy of Fallot with pulmonary atresia and major aortopulmonary collaterals (TOF/PA/MAPCAs) is a heterogeneous disease with varying degrees of severity, requiring complex anesthetic management. Our institution has adopted the approach of early complete repair with incorporation of all lung segments, extensive lobar and branch segmental pulmonary artery reconstruction, and ventricular septal defect closure. While the surgical management of TOF/PA/MAPCAs has been extensively described and varies depending on the institution, there is a paucity of literature on the anesthetic management for such procedures. Herein, we describe our anesthetic management based on our own institution’s surgical approach at Lucile Packard Children’s Hospital/Stanford University.

Extracorporeal membrane oxygenation in children with heart disease and del22q11 syndrome: a review of the Extracorporeal Life Support Organization Registry

The study objective was to evaluate outcomes among children with del22q11 (DiGeorge) syndrome supported on ECMO for heart disease. The ELSO registry database was queried to include all children <18 years undergoing heart surgery for either common atrio-ventricular canal, tetralogy of Fallot, truncus arteriosus or transposition of the great vessels and interrupted aortic arch and requiring ECMO, from 1998-2011. The outcomes evaluated included mortality, ECMO duration and length of hospital stay in patients with del22q11 syndrome and with no del22q11 syndrome. Eighty-eight ECMO runs occurred in children with del22q11 syndrome while 2694 ECMO runs occurred in children without del22q11 syndrome. For patients with heart defects receiving ECMO, del22q11 syndrome did not confer a significant mortality risk or an increased risk of infectious complications before or while on ECMO support. Neither the duration of ECMO nor mechanical ventilation prior to ECMO deployment were prolonged in patients with del22q11 syndrome compared to the controls.