Cardiac Resynchronization Therapy in Adult Congenital Heart Disease With Systemic Right Ventricle: RIGHT-CRT

Who May Qualify: - systemic right ventricle (SRV), - CRT-P or CRT-D device implanted for at least 1 month, - Age ≥18 years old, - One of the two following CRT indications: - NYHA II-IV, right ventricular ejection fraction ≤ 35% and spontaneous QRS duration ≥ 150 ms Or - NYHAI-IV, atrioventricular conduction disorders with ventricular pacing \> 40% (regardless right ventricular ejection fraction). - Affiliation to a french social security system (beneficiary or legal) - Informed and signed consent Who Should NOT Join This Trial: - Pregnancy or breastfeeding - Women of childbearing potential who do not have a negative pregnancy test and do not use one of the following methods of birth control: hormonal contraception or intrauterine device or bilateral tubal occlusion - Patient benefiting from a measure of legal protection (guardianship, curatorship, under judicial safeguard, activated future protection mandate and family authorization), - Cardiac surgery during the last 3 months or planned during the next 6 months, - Percutaneous structural cardiac intervention planned during the next 6 months, - Persistent atrial arrhythmia with catheter ablation planned during the next 6 months, - Acute congestive heart failure, - Dysfunction of at least one CRT device lead that compromise biventricular pacing, - Patient on AME - Current participation in another interventional clinical study or being in the exclusion period at the end of a previous study. Always talk to your doctor about whether this trial is right for you.