The frailty syndrome is important to consider in perioperative cardiac assistance. One of its components is the patient's sarcopenia. This can be assessed by measuring the size of the psoas muscle. For this purpose, one of the most studied measures seems to be the measurement of the Psoas Index. This is a contouring of the psoas muscle, performed on an axial section of a CT scan, at the level of the L4 vertebra, which is then matched to the body surface. However, there is no standardization of measurements and volume acquisitions, and different image processing is also described. A radiological evaluation of the psoas could overcome this difficulty and provide a rapid and available screening tool for sarcopenia.

Inclusion criteria:

• Major subject ((≥18 years old)
• Subject who underwent surgery for placement of a ventricular assist device between 01/02/2014 and 30/06/2018
• Subject who has not expressed opposition to the reuse of his or her data for research purposes

Exclusion Criteria:

• Subject having expressed opposition to participate in the study
• Absence of CT scan available at the time of implantation or CT scans older than one year prior to surgery and those older than 72 hours postoperatively
• No anthropometric data available
• Subject under legal protection
• Subject under guardianship or curatorship

Major subject ((≥18 years old) having surgery for placement of a ventricular assist device between 01/02/2014 and 30/06/2018 in Strasbourg University Hospital