Transplantation of Human Embryonic Stem Cell-derived Progenitors in Severe Heart Failure

Inclusion Criteria: * Age ≥ 18 and less than 81 years * Severe left ventricular systolic dysfunction with left ventricular ejection fraction (LVEF) ≤ 35% as assessed by echocardiography or scintigraphy * History of myocardial infarction (older than 6 months) with a residual akinesia involving more than 2 (out of 16) contiguous segments, as assessed by basal echocardiography * New York Heart Association (NYHA) Class III or IV despite optimal standard of care including diuretics and angiotensin receptor blockers and, if possible, beta blockers and aldosterone blockers * Previous implantation of an automatic internal defibrillator associated, whenever indicated, to ventricular resynchronization * Indication for a conventional cardiac surgical procedure : coronary artery bypass grafting involving, or not, the infarct area planned to be covered by the cell-loaded patch or mitral valve repair or replacement for ischemic mitral valve regurgitation; Non Eligibility to heart transplantation; Affiliation to a social security regimen * Willingness and ability to give written informed consent Exclusion Criteria: * Pregnant or potentially child-bearing women * Patients with poor echogenicity * Left ventricular aneurysm * Contra-indication to immunosuppressive drugs (history of cancer, infections like B or C hepatitis, positivity for Hepatitis-B, HIV, HTLV1) * Contra-indication to sternotomy * Alloimmunisation against the cell line from which the progenitors are derived * Cardiogenic shock or NYHA Class IV heart failure requiring need for intravenous drugs * Intellectual deterioration or psychiatric disease interfering with the ability to obtain an informed consent and to achieve a close follow-up of the patient * Noncardiac disease which may reduce life expectancy in the short term * Simultaneous participation to another trial