Heart failure goes hand in hand with a high risk of kidney injury. Kidney injury occurs in 25% of all heart failure patients and nearly doubles mortality rates. Many patient lives could be saved if clinicians could diagnose kidney injury early, enabling better patient management. Currently, rising plasma levels of creatinine are used as a marker for the onset of kidney injury. However, creatinine only rises days after irreparable damage to the kidneys has occurred. This is too late to adjust treatment of the patient, hence new early markers are needed to detect kidney injury before irreversible damage occurs. This research project aims to use mass spectrometry to identify plasma proteins involved in the first phase of kidney damage as potential new biomarkers for kidney injury. The focus will be on proteins of the cell-senescence pathway, as these molecules have been proposed as exciting biomarker candidates for acute kidney injury.