Abnormalities in lymphocyte populations in infants with neural crest cardiovascular defects

Congenital Heart Diseases and Periodontal Diseases—Is There a Link?

An understanding in the field of periodontal medicine explains the fact that the oral cavity serves as a niche for numerous pathogenic microorganisms. When these microorganisms or their by-products disseminate to the various parts of the body, they are capable of triggering diseases characterized by an altered host immune-inflammatory response in the anatomically distinct organ. This mechanism is reported in the propagation of cardiovascular diseases with respect to periodontal medicine. Abundant amount of literature suggests an association between atherosclerotic cardiovascular disease and periodontal diseases. However, there is very less data available to highlight the association between periodontal disease and non-atherosclerotic cardiovascular disease, such as congenital anomalies of the heart. This review outlines the relationship between periodontal diseases and congenital heart diseases and also helps us understand whether the presence of periodontal disease can worsen the preexisting congenital cardiac disease.

Hematological indices in pediatric patients with acyanotic congenital heart disease: a cross-sectional study of 248 patients

Background

Congenital heart disease CHD is a significant cause of mortality and morbidity in children worldwide. Patients with congenital heart disease may develop hematological problems, including thrombocytopenia and neutropenia. In addition, several studies indicate the higher frailty of patients with CHDs to infections and malignancies. Nevertheless, the mechanisms of immune system changes in these patients have remained in the shadow of uncertainty. Moreover, very few studies have worked on cytopenia in CHD. This study has assessed the frequency of thrombocytopenia, neutropenia, lymphopenia, and anemia in pediatric patients with acyanotic congenital heart disease ACHD prior to open-heart surgery.

Methods

This cross-sectional study was handled in the Pediatric Cardiology Clinic, Tehran University of Medical Sciences, during pre-operation visits from 2014 till 2019. Two hundred forty-eight children and adolescents with acyanotic congenital heart disease before open-heart surgery met the criteria to enter the study.

Results

A total of 191 (76.7%) patients with Ventricular Septal Defects (VSD), 37 (14.85%) patients with Atrial Septal Defects (ASD), and 20 (8.11%) patients with Patent Ductus Arteriosus (PDA) were enrolled in this study. The median age was 23.87 months. Thrombocytopenia and neutropenia were found, respectively, in 3 (1.2) and 23 (9.2%) patients. Hemoglobin level and lymphocyte count were significantly lower in patients with neutropenia than patients with normal neutrophil count (P value = 0.024 and P value = 0.000). Significant positive correlations were found between neutropenia and anemia. There were no correlations between neutrophil count and Platelets. Also, anemia was found in 48 patients (19.3%). The study also found a statistically significant correlation between the co-existence of VSD and neutropenia in the patients (P value = 0.000).

Conclusion

Although most were mildly neutropenic, there was a significant correlation between neutropenia and Ventricular Septal Defect compared to PDA and ASD groups. Regarding the importance of neutropenia to affect the prognosis of congenital heart defects in infections, it is important to consider further studies on the status of immune system function in these patients.

Congenital Heart Disease: An Immunological Perspective

Congenital heart disease (CHD) poses a significant global health and economic burden-despite advances in treating CHD reducing the mortality risk, globally CHD accounts for approximately 300,000 deaths yearly. Children with CHD experience both acute and chronic cardiac complications, and though treatment options have improved, some remain extremely invasive. A challenge in addressing these morbidity and mortality risks is that little is known regarding the cause of many CHDs and current evidence suggests a multifactorial etiology. Some studies implicate an immune contribution to CHD development; however, the role of the immune system is not well-understood. Defining the role of the immune and inflammatory responses in CHD therefore holds promise in elucidating mechanisms underlying these disorders and improving upon current diagnostic and treatment options. In this review, we address the current knowledge coinciding CHDs with immune and inflammatory associations, emphasizing conditions where this understanding would provide clinical benefit, and challenges in studying these mechanisms.

Relationship of thymic changes and complications after congenital heart surgery

BACKGROUND

The true role of thymic function in children with congenital heart defects is largely unknown.

AIM

To study the possible role of thymic CD3 (T-lymphocyte marker) and CD20 (B-lymphocyte marker) expression and thymic histopathological changes in complications after surgery for congenital heart defects.

METHODS

Between January and July 2014, thymic tissue samples were obtained from 13 (69% male, 31% female, mean age 10.9 ± 2 years) of 25 Iraqi patients who underwent open heart surgery with partial thymectomy for correction of congenital heart defects. The samples were evaluated for thymic expression of CD markers (CD3 and CD20) and histopathological changes. For up to 6 months after surgery, data on complications were collected from each patient, including wound infection, cardiac arrhythmias, heart failure, rehospitalization, chest infection, and death.

RESULTS

The prevalence of thymic hypoplasia was 15% and it occurred more frequently in patients with absent thymic CD3 expression (p = 0.005). Only wound infection (n = 2) and atrial fibrillation (n = 1) comprised the postoperative complications in our patients. Absence of thymic CD20 expression correlated significantly with postoperative complications and obstructive cardiac defects (p = 0.04), whereas no significant correlations were found between thymic hypoplasia with CD3 expression and postoperative complications (p > 0.05).

CONCLUSION

Patients with absent thymic CD20 expression had significantly more postoperative complications and cardiac obstructive defects than those with positive CD20 expression.

Chromosome 22q11.2 microdeletion in children with conotruncal heart defects: frequency, associated cardiovascular anomalies, and outcome following cardiac surgery

The association of conotruncal heart defects with 22q11.2 chromosomal microdeletions is well established. However, it is not clear whether particular types of conotruncal malformations or additional cardiovascular anomalies are associated with microdeletions. In addition, cardiac surgery outcome in children with conotruncal defects and del22q11.2 is not well described. We prospectively enrolled 214 children with conotruncal defects: 126 with tetralogy of Fallot (TOF), 18 with pulmonary atresia-ventricular septal defect (PA-VSD), 15 with truncus arteriosus communis (TAC) type I, one with interrupted aortic arch (IAA) type B, and 54 with the transposition of great arteries, who were consecutively hospitalized at the Pediatric Cardiology Department between 2003 and 2005. 22q11.2 microdeletion was identified by fluorescence in situ hybridization. The postoperative course following cardiac surgery was compared in patients with TOF and its more severe form, PA-VSD, with/without del22q11.2 (groups A and B) and TAC with/without del22q11.2 (groups C and D). In 15 of 214 patients, 22q11.2 microdeletion was diagnosed (in 11 with TOF/PA-VSD, in three with TAC, in one with IAA type B). In patients with TOF/PA-VSD and microdeletion anatomic features that were significantly associated with 22q11.2, deletion included right aortic arch (p = 0.018), aberrant right subclavian artery (p < 0.001), and major aortopulmonary collateral arteries (p = 0.016). A complicated postoperative course was more frequent and mortality was higher in patients with conotruncal defects and with/without microdeletion. We conclude that additional cardiovascular anomalies are significantly more frequent in children with 22q11.2 microdeletion and TOF/PA-VSD. Children with conotruncal heart defects and 22q11.2 microdeletion more frequently experienced complicated postoperative course after cardiac surgery.

The molecular basis of congenital cardiac disease

Today, congenital cardiovascular disease is virtually always amenable to corrective or palliative surgical interventions. However, the mechanisms causing developmental anomalies of the heart and vessels have remained obscure until recently. This review presents genetic defects causing the pediatric vasculopathies; Marfan's syndrome, inherited supravalvar aortic stenosis, and Williams' syndrome. A synopsis of known mutations causing human cardiomyopathies in nuclear genes encoding contractile proteins, cardiomyocyte structural proteins, and mitochondrial proteins essential for cardiac energy production is provided. The molecular genetic evidence implicating single gene mutations in the pathogenesis of conotruncal anomalies (the 22q11 monosomy or "cardiac defects, abnormal facies, thymic hypoplasia, cleft palate, and hypocalcemia with deletions on chromosome 22" [CATCH-22] syndrome), heterotaxy syndromes, trisomies and atrioventricular canal defects, and secundum atrial septal defects is presented. The consequences of these genetic causes for diagnostic evaluation and perioperative care are emphasized. Single gene defects are a common cause of congenital cardiac disease. Copyright 1998 by W.B. Saunders Company

22q11.2 microdeletions in adults with familial tetralogy of Fallot

PURPOSE

To determine the incidence of 22q11.2 microdeletions in the adult survivors of correction of tetralogy of Fallot who have familial congenital heart disease.

METHODS

Patients who had survived a correction of tetralogy of Fallot between 1954 and 1974 and had affected family members were identified during a study of these long-term survivors. Fluorescence in situ hybridization analysis was performed using both the N 25 (Oncor) and TUPLE1(VYSIS) probes, mapped to 22q11.2.

RESULTS

One of 18 (5.6%) patients had a microdeletion within 22q11.2, including both N25 and TUPLE1.

CONCLUSION

22q11.2 microdeletions involving TUPLE1 and/or N25 are present in a minority of adults with familial tetralogy of Fallot.

T cell receptor repertoire and function in patients with DiGeorge syndrome and velocardiofacial syndrome

DiGeorge syndrome (DGS) and velocardiofacial syndrome (VCFS) are associated with chromosome 22q11.2 deletion. Limited information is available on the T cell receptor (TCR) Vbeta repertoire. We therefore investigated TCR Vbeta families in lymphocytes isolated from blood and thymic samples of seven patients with DGS and seven patients with VCFS, all with 22q11.2 deletion. We also studied activities related to TCR signalling including in vitro proliferation, anti-CD3-induced protein tyrosine phosphorylation, and susceptibility to apoptosis. Reduced CD3+ T cells were observed in most patients. Spontaneous improvement of T cell numbers was detected in patients, 3 years after the first study. Analysis of CD4+ and CD8+ TCR Vbeta repertoire in peripheral and thymic cells showed a normal distribution of populations even if occasional deletions were observed. Lymphoproliferative responses to mitogens were comparable to controls as well as anti-CD3-induced protein tyrosine phosphorylation. Increased anti-CD3-mediated apoptosis was observed in thymic cells. Our data support the idea that in patients surviving the correction of cardiac anomalies, the immune defect appears milder than originally thought, suggesting development of a normal repertoire of mature T cells.

Conotruncal cardiac anomalies and otitis media

BACKGROUND

The neural crest influences the differentiation of the branchial arches, including the precursor tissue of the cardiac outflow tract and the eustachian tubes. Abnormal eustachian tubes are associated with otitis media. We hypothesized a relationship between conotruncal anomalies and eustachian tube anomalies.

METHODS

We surveyed 115 nonsyndromic patients, aged 5 to 20 years, attending a state-run pediatric cardiology clinic. The cardiac anomalies were conotruncal (transposition of the great arteries, tetralogy of Fallot, or aortic stenosis) or nonconotruncal (atrial septal defect, tricuspid atresia, atrioventricular canal). Tympanic membrane photographs were categorized independently by two physicians as to normal, abnormal (scarred or other indication of otitis proneness), or indeterminate.

RESULTS

For the 37 patients who had both ears categorized as normal or abnormal by both physicians, 20 of the 26 with a conotruncal anomaly had evidence of otitis media. In contrast, only 4 of 11 with nonconotruncal cardiac anomaly had evidence of otitis (p < 0.03; relative risk [conotruncal vs nonconotruncal], 5.83; 95% confidence interval, 1.26 to 26.95).

CONCLUSION

The concept is supported that a neural crest determined branchial field defect influences the development of the cardiac outflow tract and the eustachian tubes. Children with congenital cardiac conotruncal anomalies are otitis media prone.

Cardiac development and perinatal care of infants with neural crest-associated conotruncal defects

The neural crest constitutes a developmental field which is a morphogenetically reactive unit of the embryo. Disruption of this developmental field causes a constellation of anomalies to occur. Clustering of phenotypic abnormalities has allowed clinicians to recognize neural crest-associated syndromes with developmental abnormalities of the cardiovascular system, head, and neck. Basic research is beginning to unravel how these phenotypic characteristics are related to specific gene defects expressed during development. Currently, we do not know a one-to-one relationship between phenotypes and genotypes. These neonates with neural crest-associated conotruncal defects are born with recognizable complex cyanotic heart defects that are ductal-dependent. It may be difficult to judge if they have DiGeorge or velocardiofacial syndromes; thus, genetic counseling is of importance. Besides their life-threatening cardiovascular defects, these neonates frequently have either transient or persistent hypocalcemia or severe immunodeficiencies that require critical care management. This review will focus on the basic research underpinnings and currently recommended clinical care of infants with neural crest-associated conotruncal defects.