Congenital Heart Diseases

This project aims to evaluate a new cardiac MRI technique called the Free-Running Framework (FRF), which could simplify and accelerate the process of acquiring cardiac images. The investigators want to verify whether this method can provide functional heart measurements comparable to those obtained with traditional methods. More specifically, the goal of the study is to compare the measurements obtained with FRF to those obtained with standard sequences, to ensure they match and that this new approach can be reliably used in clinical practice. The FRF technique works differently from standard cardiac MRI. In standard exams, patients are asked to hold their breath several times and small electrodes (ECG) are used to monitor the heartbeat during the scan. These steps are needed to get clearer images of the heart as it moves. With FRF, these steps are no longer necessary: the scan is performed while patients' breath normally and without ECG monitoring. In addition, standard MRI takes multiple 2D slices of the heart, one after another. The FRF method instead captures a 3D image of the entire heart in one go, which can improve the consistency of the exam and reduce errors when doctors analyze the images later. This is all possible because the FRF method records data continuously and then organizes the images afterward based on how participants heart and breathing were moving during the exam. This helps the imager to get clear images of the heart, even without breath-holding or ECG monitoring. This project is aimed at individuals with heart disease who require cardiac MRI exams to monitor their health status (age ≥ 18 years) and are able to clearly understand the instructions provided by the research team. The investigators have already conducted small-scale technical and feasibility studies using FRF. These studies have shown that FRF is easy to use, faster than traditional methods, and provides image quality comparable to standard imaging techniques. The investigators now wish to evaluate its use in a clinical setting. More specifically, the investigators need to verify that FRF provides the same essential diagnostic information as standard techniques, so that it can be reliably used in future patient care. A maximum of 300 participants will be included in the investigation of this MRI technique between 2026 and 2031. This is a multi-center study, conducted internationally across 18 centers. This project is being carried out in compliance with Swiss legislation. The investigators follow all internationally recognized guidelines. The competent ethics committee has reviewed and approved this project.

1. Compare physical activity and cognitive functions between children having cardiac surgery with an age-matched group of children undergoing non-cardiac surgery, as well as otherwise healthy siblings or best buddies (or age and gender-matched children if no siblings or best buddies available) before surgery and after surgery or six months following initial assessment. 2. Determine the effects of a structured physical activity program for 6 months following surgery on cognitive functions and adaptive behavior in children following congenital cardiac surgery. 3. Determine the effects of a structured physical activity program for 12 months following surgery on cognitive functions and adaptive behavior in children following congenital cardiac surgery. 4. We will perform exploratory analysis to determine whether any effects of a 12-months structured physical activity program on cognitive functions and adaptive behavior persist beyond 12 months after cessation of the program.

Congenital heart disease (CHD) is defined as functional or anatomical abnormalities of the heart and major intrathoracic vessels present at birth. Impaired responses to exercise in individuals with CHD reduce exercise capacity and increase long-term mortality risk. Today, the growing population of adults with congenital heart disease (ACHD) faces chronic issues stemming from congenital abnormalities, along with muscle strength loss and a decline in activities of daily living. Once the planned treatments in this project proposal are implemented and data are obtained (especially if these data support the hypotheses), the treatment protocols applied in this study and their effects will be considered alongside the current treatment plans for individuals with CHD who experience muscle strength loss and disease-related impairment. With new treatment programs, this study aims to reduce disease-related muscle strength loss, improve disease-related outcomes, and enhance quality of life.