Congenital Heart Defects

Tetralogy of Fallot is the most common cyanotic congenital heart disease. Management strategies vary between primary repair and staged approaches including palliative surgery. The development of pulmonary arteries is a key determinant in surgical decision-making. This multicenter retrospective observational study aims to evaluate the evolution of pulmonary artery dimensions using the Nakata index at key stages of patient management (birth, palliative surgery, and complete repair). The goal is to assess its predictive value in optimizing surgical strategy and improving outcomes in patients with Tetralogy of Fallot or pulmonary atresia with ventricular septal defect.

The goal of this study is to obtain specimens and data from individuals and their families with heterotaxy and related congenital heart defects in order to clarify the molecular genetics of this disorder. The knowledge gained from the analysis of this information will provide the basis for future genetic counseling as well as contribute to knowledge about the biology of normal and abnormal development of left-right anatomic asymmetry.

Heart surgery in infants typically involves complete removal of the thymus gland to improve access to the heart. However, the thymus plays a key role in developing the immune system in early childhood, especially in the production and maturation of T lymphocytes, which help the body defend itself against infections. The THYMIC study tests the hypothesis that partial removal of the thymus (partial thymectomy) during heart surgery may better preserve the child's immune function compared to total removal (complete thymectomy). The goal is to determine whether this conservative surgical approach could reduce the risk of immune system impairment and infections in the months following surgery. This is a prospective, interventional, single-center study conducted at CHU de Nantes, involving 3 groups of infants: * One group undergoing heart surgery with complete thymectomy; * One group undergoing heart surgery with partial thymectomy; * One control group undergoing heart or non-heart surgery without thymus removal. All infants enrolled will have two blood tests: one taken during their surgery and one taken one year later. These blood tests will quantify immune cells (T, B, NK cells), levels of antibodies, and vaccine responses. Parents will also be asked to fill out a questionnaire to record any infections their child experiences during the year after surgery. By comparing the immune responses and infection rates among the groups, the researchers hope to better understand the long-term effects of thymectomy in infants. The results could support future recommendations to preserve part of the thymus when possible during heart surgery. Participation in the study does not change the medical or surgical care of the child. The decision to perform a partial or complete thymectomy is made by the surgeon based on the child's anatomy. The additional blood samples are small in volume and follow current safety regulations.

The leading cause of birth defects, Congenital Heart Defects (CHD) affect 12 million people worldwide and 41,000 newborns/year in Europe. It's a major cause of life-long morbidity and mortality, and a crucial public health issue. More than 50% of childs born with critical CHD will develop Neurodevelopmental Disorders (NDs), requiring specific care and impairing quality of life. NDs corresponds to early and lasting disturbances in cognitive, affective and behavioral development, linked to abnormalities in brain development. They are heterogeneous, affecting language, learning, motor skills, intellectual efficiency, social cognition, attention, memory and executive functions, and are associated with psychosocial difficulties (adaptive behavior, social interactions). This hidden handicap is the main long-term sequels of CHD, even before cardiovascular sequels, in individuals who often underwent multiple heart operations in early childhood. NDs concern not only complex CHD, but also simple CHD repaired in childhood and considered cured. The origin of TND associated with CHD is largely unknown. To date, few genetic or environmental causes have been clearly identified, but recent work has suggested that a common origin may link cardiac malformation and neurodevelopmental abnormality. The CATAMARAN - Pediatrics project is designed to detect potential neurodevelopmental delays associated with CHD as early as age 3, and to identify individual susceptibility factors involved in the occurrence of NDs in CHD children.

This study aims to evaluate the efficacy and safety of transcatheter bioabsorbable occluder closure in patients with outlet-type ventricular septal defect (outlet VSD), with a focus on assessing its impact on aortic valve function.

Congenital heart defects are seen in 0,8% of life births. In France this means more than 5000 newborns per year. The south-east region of France is particularly affected as a result of a higher birth rate and consanguinity, when compared to other regions. The majority of congenital heart diseases remain unexplained. Genetic causes are indisputable but remain poorly understood. Genetic research needs the availability of a large-scale DNA collection, guided by a robust phenotypic classification. Such a DNA-bank has been created in Paris (CARREG DNA bank, created by the M3C reference centre for congenital heart diseases). Such a bank is currently unavailable in south-east France. To transport biological specimens from Marseille to Paris would be very expensive. In addition, the whole infrastructure required for correct diagnosis and classification of the congenital heart diseases, for sampling, for storage of the samples and genetic analysis, does exist in our AP-HM hospital and in our AMU research unit. For those reasons it is highly preferable to elaborate such a database and DNA-bank locally. The acronym SEA-HD (South-EAst-Heart-Diseases) would be used to name this DNA-bank