Infant With Trisomy 18 and Hypoplastic Left Heart Syndrome

The American Association for Thoracic Surgery (AATS) 2023 Expert Consensus Document: Recommendation for the care of children with trisomy 13 or trisomy 18 and a congenital heart defect

OBJECTIVES

Recommendations for surgical repair of a congenital heart defect in children with trisomy 13 or trisomy 18 remain controversial, are subject to biases, and are largely unsupported with limited empirical data. This has created significant distrust and uncertainty among parents and could potentially lead to suboptimal care for patients. A working group, representing several clinical specialties involved with the care of these children, developed recommendations to assist in the decision-making process for congenital heart defect care in this population. The goal of these recommendations is to provide families and their health care teams with a framework for clinical decision making based on the literature and expert opinions.

METHODS

This project was performed under the auspices of the AATS Congenital Heart Surgery Evidence-Based Medicine Taskforce. A Patient/Population, Intervention, Comparison/Control, Outcome process was used to generate preliminary statements and recommendations to address various aspects related to cardiac surgery in children with trisomy 13 or trisomy 18. Delphi methodology was then used iteratively to generate consensus among the group using a structured communication process.

RESULTS

Nine recommendations were developed from a set of initial statements that arose from the Patient/Population, Intervention, Comparison/Control, Outcome process methodology following the groups' review of more than 500 articles. These recommendations were adjudicated by this group of experts using a modified Delphi process in a reproducible fashion and make up the current publication. The Class (strength) of recommendations was usually Class IIa (moderate benefit), and the overall level (quality) of evidence was level C-limited data.

CONCLUSIONS

This is the first set of recommendations collated by an expert multidisciplinary group to address specific issues around indications for surgical intervention in children with trisomy 13 or trisomy 18 with congenital heart defect. Based on our analysis of recent data, we recommend that decisions should not be based solely on the presence of trisomy but, instead, should be made on a case-by-case basis, considering both the severity of the baby's heart disease as well as the presence of other anomalies. These recommendations offer a framework to assist parents and clinicians in surgical decision making for children who have trisomy 13 or trisomy 18 with congenital heart defect.

Molecular Pathways and Animal Models of Hypoplastic Left Heart Syndrome

Hypoplastic left heart syndrome (HLHS) is a severe congenital heart disease (CHD) with underdevelopment of left-sided heart structures. While previously uniformly fatal, surgical advances now provide highly effective palliation that allows most HLHS patients to survive their critical CHD. Nevertheless, there remains high morbidity and mortality with high risk of heart failure. As hemodynamic compromise from restricted aortic blood flow has been suggested to underlie the poor LV growth, this suggests the possibility of prenatal fetal intervention to recover LV growth. As such interventions have yielded ambiguous results, the optimization of therapy will require more mechanistic insights into the developmental etiology for HLHS. Clinical studies have shown high heritability for HLHS, with an oligogenic etiology indicated in conjunction with genetic heterogeneity. This is corroborated with the recent recovery of mutant mice with HLHS. With availability-induced pluripotent stem cell (iPSC)-derived cardiomyocytes from HLHS mice and patients, new insights have emerged into the cellular and molecular etiology for the LV hypoplasia in HLHS. Cell proliferation defects were observed in conjunction with metaphase arrest and the disturbance of Hippo-YAP signaling. The left-sided restriction of the ventricular hypoplasia may result from epigenetic perturbation of pathways regulating left-right patterning. These findings suggest new avenues for fetal interventions with therapies using existing drugs that target the Hippo-YAP pathway and/or modulate epigenetic regulation.

Variants in FREM1 and trisomy 18 identified in a neonatal progeria patient

BACKGROUND

Neonatal progeroid disorders are rare disorders with clinical features including low body mass index, proptosis, aged and dysmorphic facial features at the time of birth, prominent veins, sparse scalp hairs, and severe growth retardation. Very few cases have been identified with an unknown genetic cause. Here, we report clinical and genetic findings of a proband with hallmark features of neonatal progeria.

METHODS

Microarray comparative genomic hybridization, whole exome sequencing (WES) and Sanger sequencing were performed using standard methods.

RESULTS

Array combined genome hybridization data revealed trisomy 18 in the proband (II-1), and WES data identified novel compound heterozygous variants (c.247 C > T; p.H83Y and c.14769868InsA) in the FREM1 gene.

CONCLUSION

We report a novel complex case of neonatal progeria with atrial septal defects, trisomy 18 without typical features of Edward syndrome. The phenotype of the patient was more consistent with neonatal progeria, thus we speculate it to be caused by the FREM1 variants.

Focus on the frontier issue: progress in noninvasive prenatal screening for fetal trisomy from clinical perspectives

The discovery of cell-free fetal DNA (cffDNA) in maternal blood and the rapid development of massively parallel sequencing have revolutionized prenatal testing from invasive to noninvasive. Noninvasive prenatal screening (NIPS) based on cffDNA enables the detection of fetal trisomy through sequencing, comparison, and bioassays. Its accuracy is better than that of traditional screening methods, and it is the most advanced clinical application of high-throughput sequencing technologies. However, the existing sequencing methods are limited by high costs and complex sequencing procedures. These limitations restrict the availability of NIPS for pregnant women. Many amplification methods have been developed to overcome the limitations of sequencing methods. The rapid development of non-sequencing methods has not been accompanied by reviews to summarize them. In this review, we initially describe the detection principles for sequencing-based NIPS. We summarize the rapidly evolving amplification technologies, focusing on the need to reduce costs and simplify the procedures. To ensure that the testing systems are feasible and that the testing processes are reliable, we expand our vision to the clinic. We evaluate the clinical validity of NIPS in terms of sensitivity, specificity, and positive predictive value. Finally, we summarize the application guidelines and discuss the corresponding quality control methods for NIPS. In addition to cffDNA, extracellular vesicle DNA, RNA, protein/peptide, and fetal cells can also be detected as biomarkers of NIPS. With the development of prenatal testing, NIPS has become increasingly important. Notably, NIPS is a screening test instead of a diagnostic test. The testing methods and procedures used in the NIPS process require standardization.

Pediatric Cardiac Surgical Patterns of Practice and Outcomes in Japan and Europe

OBJECTIVES

The Japan Cardiovascular Surgery Database-Congenital section (JCVSD-Congenital) and the European Congenital Heart Surgeons Association (ECHSA) Congenital Heart Surgery Database (CHSD) share the same nomenclature. We aimed at comparing congenital cardiac surgical patterns of practice and outcomes in Japan and Europe using the JCVSD-Congenital and ECHSA-CHSD.

METHODS AND RESULTS

We examined Japanese (120 units, 63,365 operations) and European (96 units, 90,098 operations) data in JCVSD-Congenital and ECHSA-CHSD from 2011 to 2017. Patients' age and weight, periprocedural times, mortality at hospital discharge, and postoperative length of stay were calculated for ten benchmark operations. There was a significantly higher proportion of ventricular septal defect closures and Glenn operations and a significantly lower proportion of coarctation repairs, tetralogy of Fallot repairs, atrioventricular septal defect repairs, arterial switch operations, truncus repairs, Norwood operations, and Fontan operations in JCVSD-Congenital compared to ECHSA-CHSD. Postoperative length of stay was significantly longer following all benchmark operations in JCVSD-Congenital compared to ECHSA-CHSD. Mean STAT mortality score (Society of Thoracic Surgeons European Association for Cardio-Thoracic Surgery mortality score) was significantly higher in JCVSD-Congenital (0.78) compared to ECHSA-CHSD (0.71). Mortality at hospital discharge was significantly lower in JCVSD-Congenital (4.2%) compared to ECHSA-CHSD (6.0%, P < .001).

CONCLUSIONS

The distribution of the benchmark procedures and age at the time of surgery differ between Japan and Europe. Postoperative length of stay is longer, and the mean complexity is higher in Japan compared to European data. These comparisons of patterns of practice and outcomes demonstrate opportunities for continuing bidirectional transcontinental collaboration and quality improvement.

Disagreement About Surgical Intervention in Trisomy 18

In this case, we explore physician conflict with performing surgery (tracheostomy) for long-term ventilation in a term infant with trisomy 18 and respiratory failure. Experts in neonatal-perinatal medicine, pediatric bioethics, and pediatric palliative care have provided comments on this case. An additional commentary was written by the parent of another infant with trisomy 18, who is also a medical provider (physical therapist).

Ethical considerations for cardiac surgical interventions in children with trisomy 13 and trisomy 18

Medical and surgical approaches to children with trisomy 13 and 18 are evolving, and an increasing number of patients are being considered for simple and complex cardiac procedures. This review describes how the shifts in medical and social considerations for children with trisomy 13 and 18 mirror the shifts that occurred 50 years ago for children with trisomy 21. Yet the variability in cardiac lesions, and variability in non-cardiac comorbidities, is much greater for patients with trisomy 13 and 18 than for those with trisomy 21. That variability, combined with the severe neurologic impairment in survivors, complicates the current risk: benefit balance of surgical intervention. Consistent approaches to care for these patients should be built on an evidence base, and should include contributions from specialists in medical ethics and palliative care.