Preventing contrAst Induced Nephropathy After TranscathEter Aortic Valve Replacement

Inclusion Criteria: 1. Patient has provided written informed consent. 2. Patient is undergoing TAVI. 3. Patient has an estimated GFR \<60ml/min/1.73m2. Exclusion Criteria: 1. Patient has end-stage kidney disease requiring dialysis. 2. Emergent TAVI (planned before next working day). 3. Recent exposure to radiographic contrast agents (within 2 days prior to the TAVI). 4. Allergy to contrast agent. 5. Planned administration of dopamine, mannitol, fenoldopam or N-acetylcysteine during the intended time of the study. 6. Need for continuous hydration therapy (e.g. sepsis). 7. Multiple myeloma. 8. Contra-indication to sodium bicarbonate.