Perspective on Congenital Heart Disease Research

Role and mechanism of miR-871-3p/Megf8 in regulating formaldehyde-induced cardiomyocyte inflammation and congenital heart disease

OBJECTIVE AND DESIGN

We aimed to investigate the molecular mechanism underlying formaldehyde (FA)-induced congenital heart disease (CHD) using in vitro and in vivo models.

MATERIALS AND SUBJECTS

Neonatal rat heart tissues and H9C2 cells were used for in vitro studies, while FA-exposed new-born rats were used for in vivo studies.

TREATMENT

H9C2 cells were exposed to FA concentrations of 0, 50, 100 and 150 μM/mL for 24 h.

METHODS

Whole transcriptome gene sequencing identified differentially expressed miRNAs in neonatal rat heart tissues, while Real-time quantitative PCR (RT-qPCR) assessed miR-871-3p and Megf8 expression. RNA pull-down and dual-luciferase reporter assays determined miR-871-3p and Megf8 relationships. Inflammatory cytokine expression was assessed by western blotting. A FA-induced CHD model was used to validate miR-871-3p regulatory effects in vivo.

RESULTS

We identified 89 differentially expressed miRNAs, with 28 up-regulated and 61 down-regulated (fold change ≥ 2.0, P < 0.05). Inflammation (interleukin) and signalling pathways were found to control FA-induced cardiac dysplasia. miR-871-3p was upregulated in FA-exposed heart tissues, modulated inflammation, and directly targeted Megf8. In vivo experiments showed miR-871-3p knockdown inhibited FA-induced inflammation and CHD.

CONCLUSION

We demonstrated miR-871-3p's role in FA-induced CHD by targeting Megf8, providing potential targets for CHD intervention and improved diagnosis and treatment strategies.

Neuromental health aspects in adults with CHD after cardiopulmonary bypass intervention during childhood

OBJECTIVE

It is often assumed, that adult patients with CHD (ACHD) have impairments regarding their cognitive function (CF) and health-related quality of life. In particular, it seems reasonable to assume that cyanosis may have a potential impact on CF as well as surgical or drug treatment into adulthood. This study assesses neuromental health aspects such as CF and health-related quality of life in ACHD patients.

METHODS

Seventy-eight ACHD patients (female n = 39 (50%); 34.1 ± 12.9 years; cyanotic CHD n = 49 (62.8%) with a cyanosis duration of 159.8 ± 196.2 month) who underwent open heart surgery as first intervention were asked to participate during routinely follow-up in 2018. Wechsler Intelligence Scale IV was used for CF and the Short Form 36 Health Survey to assess health-related quality of life.

RESULTS

Intelligence quotient measures showed significant differences comparing never cyanotic and with a cyanotic phase in verbal comprehension (p = 0.013). There was no association of CF with cyanosis duration, number of surgery or catheter, CHD severity, and time of first surgery. The group of early surgery showed significantly better results in physical function (p = 0.040) of health-related quality of life, and in comparison with their assigned reference, both groups showed significantly reduced results in all domains except in bodily pain and mental health. Full-Scale intelligence quotient correlates with physical function of health-related quality of life.

CONCLUSIONS

The results show normal CF in ACHD. Health-related quality of life was weak in comparison with the reference. There is a need to improve the well-being of our ACHD with structured programmes, including physical activity programmes. This growing ACHD population should be focused in order of their needs, medical ones on one hand and on the other hand psychosocial matters.

Cognitive function in adults with Fontan palliation versus acyanotic CHD patients and association with health-related quality of life

BACKGROUND

Impairments and developmental delay are often reported in infants and young children with CHD. However, currently, there is no data regarding cognitive abilities assessed by standardised intelligence tests in adults with CHD. This study assesses the cognitive function in Fontan patients compared with acyanotic CHD patients whether restrictions in cognitive function are present in adulthood and its association with health-related quality of life.

METHODS

Forty-four adult CHD (female n = 21 (47.7%); mean age 34.7 ± 11.9 years), 22 with Fontan circulation and 22 with acyanotic CHD, underwent the Wechsler Intelligence Scale for adults as patients during routine follow-up in 2018. The Medical Outcomes Study Questionnaire Short-Form 36 Health Survey (SF-36) assessed health-related quality of life.

RESULTS

Fontan patients showed significantly better results in the FSIQ (p = 0.020) and perceptual reasoning (p = 0.017) in comparison with patients with acyanotic CHD. All adult CHD patients showed normal IQ in subscales and full-scale IQ (FSIQ). In health-related quality of life, no association with cognitive function was found and no significant difference between both CHD groups, but trends to reduced values in acyanotic adult CHD.

CONCLUSIONS

Interestingly, our study results in adult Fontan patients showed that it is possible to live an adult life with normal cognitive function and good health-related quality of life with a univentricular heart. Thus, this study could be a guidepost for more in-depth studies on cognitive function in Fontan survivors. In addition, the focus should be on health-related quality of life of adult CHD with simple CHD in particular, since a reduced health-related quality of life is not only medically based.

Comprehensive profile of circRNAs in formaldehyde induced heart development

Circular RNAs (circRNAs) are a novel type of long non-coding RNAs that can regulate gene expression in heart development and heart disease. However, the expression pattern of circRNAs in congenital heart disease (CHD) induced by formaldehyde exposure is still unknown. We detected circRNAs expression profiles in heart tissue taken from six neonatal rat pups with formaldehyde exposure group and normal group using RNA-sequencing. Results revealed that a total of 54 circRNAs were dysregulated in the formaldehyde exposure group compared to the normal group. Among them, 31 were upregulated and 23 were downregulated (fold change = 2.0, p < 0.0 5). The qRT-qPCR results showed that expressions of 12:628708|632694, 18:77477060|77520779, 5:167486001|167526275 were significantly upregulated, while that of 7:41167312|4116775 and 20:50659751|5068786 were notably downregulated; the expression pattern was consistent with the RNA sequencing data. Bioinformatics analysis shows that the pathogenesis of formaldehyde exposure-induced CHD may involve Hippo-YAP pathway、Notch signaling pathway and other pathways. A key miRNA (rno-miR-665) was identified by constructing a circRNA-miRNA-mRNA co-expression network. In summary, the study illustrated that circRNAs differentially expressed in fetal heart tissues during formaldehyde exposure has potential biological functions and may be a biomarker or therapeutic target for CHD.

State of the science and future research directions in palliative and end-of-life care in paediatric cardiology: a report from the Harvard Radcliffe Accelerator Workshop

Workshop proceedings, priorities, and recommendations from the "State of the Science and Future Directions in Palliative and End-of-Life Care in Pediatric Cardiology," a Harvard Radcliffe Accelerator Workshop, are detailed. Eight priorities for research were identified, including patient and family decision making, communication, patient and family experience, patient symptom measurement and management, training and curriculum development, teamwork, family hardships and bereavement, and ethical considerations. Barriers to research in this area were also identified: lack of outcome/measurement tools, lack of research funding, small population sizes, lack of effort/protected time for research, undervalued research topic by field and colleagues, and heterogeneous research participant diversity. Priorities and barriers were mostly consistent with those reported by the field of paediatric palliative care at large. These collective, consensus-based findings from diverse, multidisciplinary leaders in the field, as well as parent representatives, provide a catalyst for scientific advancement specific to paediatric and end-of-life care in paediatric cardiology.

A National Comparative Investigation of Twins With Congenital Heart Defects for Neurodevelopmental Outcomes and Quality of Life (Same Same, but Different?): Protocol for a Prospective Observational Study

Background

Due to the increased survival rates of patients with congenital heart defects (CHD), associated disorders are an increasing focus of research. Existing studies figured out an association between CHD and its treatment, and neurodevelopmental outcomes including motor competence impairments. All these studies, however, compared their test results with reference values or results of healthy control groups. This comparison is influenced by socioeconomic and genetic aspects, which do have a known impact on neurodevelopmental outcomes.

Objective

This study protocol describes a setting that aims to find out the role of CHD and its treatments on neurodevelopmental outcomes, excluding socioeconomic and genetic aspects. Only a twin comparison provides the possibility to exclude these confounding factors.

Methods

In a German-wide prospective cohort study, 129 twin siblings registered in the National Register for Congenital Heart Defects will undergo testing on cognitive function (Wechsler Intelligence Tests age-dependent: Wechsler Adult Intelligence Scale, fourth edition; Wechsler Intelligence Scale for Children, fifth edition; and Wechsler Preschool and Primary Scale of Intelligence, fourth edition) and motor competence (Movement Assessment Battery for Children, second edition). Additionally, the self-reported health-related quality of life (KINDL-R for children, Short Form 36 for adults) and the parent-reported strength and difficulties of the children (Strength and Difficulties Questionnaire, German version) will be assessed by standardized questionnaires. CHD data on the specific diagnosis, surgeries, transcatheter procedures, and additional medical information will be received from patient records.

Results

The approval of the Medical Ethics Committee Charité Mitte was obtained in June 2018. After getting funded in April 2019, the first enrollment was in August 2019. The study is still ongoing until June 2022. Final results are expected in 2022.

Conclusions

This study protocol provides an overview of the study design’s technical details, offering an option to exclude confounding factors on neurodevelopmental outcomes in patients with CHD. This will enable a specific analysis focusing on CHD and clinical treatments to differentiate in terms of neurodevelopmental outcomes of patients with CHD compared to twin siblings with healthy hearts. Finally, we aim to clearly define what is important to prevent patients with CHD in terms of neurodevelopmental impairments to be able to develop targeted prevention strategies for patients with CHD.

Trial Registration

German Clinical Trials Register DRKS00021087; https://tinyurl.com/2rdw8w67

International Registered Report Identifier (IRRID)

DERR1-10.2196/26404

Historical investigation of medical treatment for adult congenital heart disease: A Canadian perspective

OBJECTIVE

The number of adults with congenital heart disease (CHD) has increased substantially because of medical advances that are extending life expectancy beyond childhood. A historical investigation is timely not only because of this significant demographic shift, but also because stakeholder engagement is increasingly important in shaping research directions. The study questions were: From the perspective of stakeholders, what is known about the medical treatment for the adult CHD cohort in Canada and how has it changed over time?

DESIGN/METHODS

We harnessed the use of historical research methods and conducted interviews with 21 key informants in order to articulate a contextualized understanding of the evolution of adult CHD treatment in Canada. The informants recruited were currently or previously located in and/or involved in treatment in seven provinces and two territories across Canada including patients, families, advocates, researchers, and practitioners located in disciplines that included cardiology, cardiovascular surgery, nursing, psychology, dietetics, and kinesiology.

RESULTS

Alongside findings that highlighted the significant demographic shift, the findings highlight key themes related to temporal shifts in treatment, emergence of organizational structures and use of evidence, comprehensive approaches to care, and future directions. A critical finding that requires immediate attention is the significantly disproportionate resources to the number of adults living with CHD, and as a result, the real risk of premature death for this population.

CONCLUSIONS

The insights provided behoove the community of stakeholders to think creatively on how to draw attention to the inadequacy of resources and the unique and diverse needs of this population.

The Pediatric Heart Network Scholar Award programme: a unique mentored award embedded within a multicentre network

BACKGROUND

The Pediatric Heart Network designed a career development award to train the next generation of clinician scientists in paediatric-cardiology-related research, a historically underfunded area. We sought to identify the strengths/weaknesses of the programme and describe the scholars' academic achievements and the network's return on investment.

METHODS

Survey questions designed to evaluate the programme were sent to applicants - 13 funded and 19 unfunded applicants - and 20 mentors and/or principal investigators. Response distributions were calculated. χ2 tests of association assessed differences in ratings of the application/selection processes among funded scholars, unfunded applicants, and mentors/principal investigators. Scholars reported post-funding academic achievements.

RESULTS

Survey response rates were 88% for applicants and 100% for mentor/principal investigators. Clarity and fairness of the review were rated as "clear/fair" or "very clear/very fair" by 98% of respondents, but the responses varied among funded scholars, unfunded applicants, and mentors/principal investigators (clarity χ2=10.85, p=0.03; fairness χ2=16.97, p=0.002). Nearly half of the unfunded applicants rated feedback as "not useful" (47%). "Expanding their collaborative network" and "increasing publication potential" were the highest-rated benefits for scholars. Mentors/principal investigators found the programme "very" valuable for the scholars (100%) and the network (75%). The 13 scholars were first/senior authors for 97 abstracts and 109 manuscripts, served on 22 Pediatric Heart Network committees, and were awarded $9,673,660 in subsequent extramural funding for a return of ~$10 for every scholar dollar spent.

CONCLUSIONS

Overall, patient satisfaction with the Scholar Award was high and scholars met many academic markers of success. Despite this, programme challenges were identified and improvement strategies were developed.

Impact of Cardiac Progenitor Cells on Heart Failure and Survival in Single Ventricle Congenital Heart Disease

RATIONALE

Intracoronary administration of cardiosphere-derived cells (CDCs) in patients with single ventricles resulted in a short-term improvement in cardiac function.

OBJECTIVE

To test the hypothesis that CDC infusion is associated with improved cardiac function and reduced mortality in patients with heart failure.

METHODS AND RESULTS

We evaluated the effectiveness of CDCs using an integrated cohort study in 101 patients with single ventricles, including 41 patients who received CDC infusion and 60 controls treated with staged palliation alone. Heart failure with preserved ejection fraction (EF) or reduced EF was stratified by the cardiac function after surgical reconstruction. The main outcome measure was to evaluate the magnitude of improvement in cardiac function and all-cause mortality at 2 years. Animal studies were conducted to clarify the underlying mechanisms of heart failure with preserved EF and heart failure with reduced EF phenotypes. At 2 years, CDC infusion increased ventricular function (stage 2: +8.4±10.0% versus +1.6±6.4%, P=0.03; stage 3: +7.9±7.5% versus -1.1±5.5%, P<0.001) compared with controls. In all available follow-up data, survival did not differ between the 2 groups (log-rank P=0.225), whereas overall patients treated by CDCs had lower incidences of late failure (P=0.022), adverse events (P=0.013), and catheter intervention (P=0.005) compared with controls. CDC infusion was associated with a lower risk of adverse events (hazard ratio, 0.411; 95% CI, 0.179-0.942; P=0.036). Notably, CDC infusion reduced mortality (P=0.038) and late complications (P<0.05) in patients with heart failure with reduced EF but not with heart failure with preserved EF. CDC-treated rats significantly reversed myocardial fibrosis with differential collagen deposition and inflammatory responses between the heart failure phenotypes.

CONCLUSIONS

CDC administration in patients with single ventricles showed favorable effects on ventricular function and was associated with reduced late complications except for all-cause mortality after staged procedures. Patients with heart failure with reduced EF but not heart failure with preserved EF treated by CDCs resulted in significant improvement in clinical outcome.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifiers: NCT01273857 and NCT01829750.

Differential Expression of CircRNAs in Embryonic Heart Tissue Associated with Ventricular Septal Defect

Objectives: To explore and validate the differential expression of circRNAs in the myocardium of congenital ventricular septal defect (VSD) and to explore a new avenue of research regarding the pathological mechanisms of VSD. Methods: We detected circRNAs expression profiles in heart tissues taken from six aborted fetuses with VSD and normal group using circRNA microarray. Some differentially expressed circRNAs were studied by bioinformatics analysis. Finally, quantitative reverse transcription polymerase chain reaction (qRT-PCR) was performed to confirm these results. Results: This study found abundant circRNAs in the myocardium taken from individuals in the normal group and the VSD group. After that, totally 6234 differentially expressed circRNAs between the normal group and the VSD group were confirmed (Fold change ≥ 2.0; p < 0.05). Then, this research carried out bioinformatics analysis and predicted the potential biological functions of circRNAs. Finally, the over-expression of hsa_circRNA_002086 and under-expression of hsa_circRNA_007878, hsa_circRNA_100709, hsa_circRNA_101965, hsa_circRNA_402565 were further validated by qRT-PCR. Conclusions: There is a significant difference in expression of the circRNA in cardiac tissue from VSD group compared to the normal group. Combined with the microarray results and previous researches, circRNAs may contribute to the occurrence of VSD by acting as miRNA sponges or by binding proteins, these possible roles for circRNAs in VSD require elucidation in additional studies.

Physiology of Cardiac Development: From Genetics to Signaling to Therapeutic Strategies

The heart is one of the first organs to form and function during embryonic development. It is comprised of multiple cell lineages, each integral for proper cardiac development, and include cardiomyocytes, endothelial cells, epicardial cells and neural crest cells. The molecular mechanisms regulating cardiac development and morphogenesis are dependent on signaling crosstalk between multiple lineages through paracrine interactions, cell-ECM interactions, and cell-cell interactions, which together, help facilitate survival, growth, proliferation, differentiation and migration of cardiac tissue. Aberrant regulation of any of these processes can induce developmental disorders and pathological phenotypes. Here, we will discuss each of these processes, the genetic factors that contribute to each step of cardiac development, as well as the current and future therapeutic targets and mechanisms of heart development and disease. Understanding the complex interactions that regulate cardiac development, proliferation and differentiation is not only vital to understanding the causes of congenital heart defects, but to also finding new therapeutics that can treat both pediatric and adult cardiac disease in the near future.