Study of Adaptation of the Right Ventricle to Systemic Afterload

Study Overview
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Brief Summary
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the first purpose of the study is to determine the adaptative mechanisms of right ventricle (RV) to systemic afterload, and the mechanisms of RV failure, in patients with congenital heart disease and subaortic RV, using cardiac magnetic resonance imaging (CMR).The mechanisms are evaluated by measures of RV remodelling and RV wall stress using CMR. Second objectives are to evaluate these mechanisms using echography, arterial properties study and neurohormonal levels

Detailed Description
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Right ventricle (RV) in sub-aortic position is a rare situation, mainly in two congenital heart defects: congenitally corrected transposition of the great arteries and complete transposition of the great arteries palliated by atrial switch. In these patients, increase of afterload leads to hypertrophy and late RV dilatation. The stress exercised on RV walls could play a role in adaptative mechanisms to systemic afterload. Beyond a remodelling threshold, it could cause fibrosis damage and RV systolic failure. Magnetic resonance imaging, which has a major potential in estimation of RV remodelling, wall stress and fibrosis, could shed light on RV adaptation to systemic afterload and evolution towards failure. Systemic RV remodelling and function could also depend on the neuro-hormone secretion and mechanical arterial properties, that have a direct influence on patients afterload. The first purpose of the study is to determine the adaptative mechanisms of RV to systemic afterload, and the mechanisms of RV failure, in patients with congenital heart disease and subaortic RV, using cardiac magnetic resonance imaging (CMR).The mechanisms are evaluated by measures of RV remodelling and RV wall stress using CMR. Second objectives are to evaluate these mechanisms using echography, arterial properties study and neurohormonal levels

Official Title
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Study of Adaptation of the Right Ventricle to Systemic Afterload

Conditions
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Congenital Heart Disease With Systemic Right Ventricle

Intervention / Treatment
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* Other: asymptomatic group
* Other: symptomatic group


Participation Criteria
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Eligibility Criteria
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Patients inclusion criteria: patients with a systemic right ventricle to have an insurance to obtain informed consent Patients non-inclusion criteria: patients with cyanosis defined by a saturation ≤ 85% at rest patients with a ventricular septal defect non repaired at the time of inclusion contraindications normal MRI contraindication to achieving a stress test Glomerular Filtration Rate inf 30ml/mn/1.73m² physical or mental disability that does not allow to perform a cardiopulmonary exercise test patients with already severe allergy to gadolinium MRI contrast current Pregnancy patients who can not be monitored over the period of one year, patient participating in another research on the Treatment interacting with the neurohormonal system in particular the renin-angiotensin-aldosterone system healthy subjects inclusion criteria: matched for age and sex + / - 5 years of an asymptomatic patient Normal ECG normal Echocardiography clinical examination prior Patient receiving an insurance Obtaining informed consent healthy subjects Exclusion criteria: History of myocardial infarction-known or detectable on the ECG-abnormal Liver function tests Complete Blood Count electrolytes viral serology Primary or secondary cardiomyopathy-known or detectable on echocardiography History of thoracic radiotherapy or chemotherapy Contraindications MRI Counter-indication for performing a stress test Patient with severe renal clearance less than Glomerular Filtration Rate inf 30ml/mn/1.73m² Patient has already made a severe allergy to gadolinium MRI contrast Current Pregnancy

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: asymptomatic group<br>patients with systemic right ventricle who are asymptomatic, | Other: asymptomatic group<br>* 2 visits with MRI<br>|
| Sham Comparator: symptomatic group<br>symptomatic group : patients with systemic right ventricle and heart failure signs and/or decrease exercise performance | Other: symptomatic group<br>* 2 visits with MRI<br>|
| Sham Comparator: control<br>healthy subject matched with patients of asymptomatic group | Other: asymptomatic group<br>* 2 visits with MRI<br>Other: symptomatic group<br>* 2 visits with MRI<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| remodelling indexes |  | 48 months | 
| wall stress index |  | 48 months | 
| fibrosis of systemic RV measured by MRI |  | 48 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| echographic measures of RV function and geometry indexes | comparison between patients and healthy subjects and analysis of the evolution of the measured parameters in the 2 groups after one year of follow | 48 months | 
| Arterial mechanical properties (stiffness aortic distensibility and arterial compliance) | comparison between patients and healthy subjects and analysis of the evolution of the measured parameters in the 2 groups after one year of follow | 48 months | 
| Rate of neurohormones of the renin-angiotensin-aldosterone system and neuropeptides |  | 48 months | 
| Variability and reproducibility indices remodeling and wall stress MRI | inter and intra-observer variability and inter-examination MRI measures | 48 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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systemic right ventricle, cardiac magnetic resonance imaging, congenital heart disease