Pilot Study to Establish a Repertoire of Megakaryocyte Markers, Quantifiable by Spectral Flow Cytometry, in Bone Marrow and Circulating in Patients Undergoing Cardiac Surgery for Bypass Grafting

Inclusion Criteria: \- Age over 18 * Indication for programmed cardiac surgery, specifically coronary artery bypass grafting with sternotomy * Up to date social security coverage * Patients able to understand the purpose and constraints of the research project Exclusion Criteria: * Refusal to participate in the study, * Pregnant and/or breastfeeding women (clinical interview), * Unscheduled cardiac surgery, Acquired hematologic disorders (acute leukemia, lymphomas, myelodysplastic syndromes, and myeloproliferative syndromes) * Treatment with thrombopoietin receptor agonists * Treatment with anti-inflammatory (included corticoids) or/and immunosuppressors * Hematopoietic stem cell transplantation or organ transplantation * Active cancer with or without treatment (in remission, ongoing or treated within the last 6 months), * Palliative care patients * Any other type of cardiac surgery and previous sternotomy, * History of external thoracic radiotherapy, * Patient under legal protection (curatorship, guardianship or safeguard of justice) * Patients with ongoing clinical trial requiring collection of additional blood or bone marrow samples