Levosimendan, a drug with inotropic, vasodilatory and myocardial protective properties, has been proposed for the prevention and treatment of postoperative low cardiac output syndrome in cardiac surgery. Despite preliminary studies with promising results, large randomized controlled trials aimed at demonstrating the benefits of levosimendan did not show superiority over placebo in this indication. However, in these studies, the infusion was neither performed at the maximum dosage nor during the 24 hours preceding the surgery, but mainly at the very beginning of the operation. However, post hoc analyses showed a reduction in mortality and in the occurrence of low cardiac output syndrome in the subgroup of patients who had undergone isolated coronary artery bypass grafting, in contrast to those who had undergone valvular or combined surgery. Another recent study suggests that under similar conditions, preconditioning with levosimendan started 48 hours before surgery reduces the length of stay in intensive care and the average cost of hospitalization. There are no formal recommendations on the prophylactic use of levosimendan in cardiac surgery for heart failure patients with impaired LVAS. However, the France-Levo registry, a multicenter observational study requested by the HAS, has shown that in real practice there is a place for preconditioning with levosimendan, which is used in this indication for 7% of the patients in the registry. The Cardiovascular Surgery and Transplantation Department of the Nancy Brabois University Hospital, which actively participated in the France-Levo registry, is one of the cardiac surgery centers that uses this practice, as is the University Hospital of Rouen. It is interesting to be able to evaluate retrospectively whether levosimendan preconditioning has a positive impact on the postoperative prognosis of patients and more particularly on the reduction of the length of stay in critical care and in hospital compared to standard management.

Inclusion Criteria:

• Patients with heart failure impaired LVEF (< 40%), who have undergone left heart surgery (coronary artery bypass grafting and/or mitral and/or aortic valve replacement) under extracorporeal circulation between 01/01/2018 and 28/02/2022 at the Nancy University Hospital or the University Hospital of Rennes, Rouen or Amiens

Exclusion Criteria:

• Initiation of levosimendan > 48 hours or < 24 hours before surgery
• ECMO pre- or post-op

Preoperative heart failure patients with impaired LVEF who underwent left heart surgery (coronary artery bypass grafting and/or mitral and/or aortic valve replacement) under extracorporeal circulation from 01/09/2018 to 28/02/2022 at the CHRU de Nancy, CHRU de Rennes, CHRU de Rouen or CHRU d'Amiens.