Table 2 Inclusion and exclusion criteria

Inclusion criteria

Adults aged 18–89 years having single or multiple heart valve repair or replacement as a first time or redo operation as an elective or urgent procedure (i.e. non-emergency procedure), who are able to give informed consent.

Patients with or without concomitant procedures. Concomitant procedures may include but are not restricted to: coronary artery bypass graft (CABG), ascending aortic and/or root replacement, and ablation for atrial fibrillation.

Baseline urea and creatinine levels are within normal range, defined as follows: urea 2.5 to 7.8 mmol/L; creatinine 45 to 90 μmol/L for women and 60 to 110 μmol/L for men.

Exclusion criteria

Baseline eGFR< 30 mls/min/1.73 m2

Patients on renal replacement therapy

Planned deep hypothermic circulatory arrest with cardiopulmonary bypass switched off