Clinical Research Directory

Inclusion Criteria: * 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 Exclusion Criteria: * 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.