Groundbreaking Renal Assist Device Intervening to ENhance cardioThoracic Surgery Outcomes

Inclusion Criteria: To be eligible for participation in this study, an individual must meet all the following criteria: 1. A candidate for elective or urgent on-pump coronary artery bypass grafting (CABG) and/or valvular surgery 2. Male or Female age 22 to 85 years 3. Estimated glomerular filtration rate (eGFR) 15 - 60 mL/min/1.73m2 4. Signed and dated informed consent 5. Female patients of childbearing potential must: 1. have negative pregnancy test at the informed consent visit, 2. be using previously initiated approved and effective contraception from the informed consent visit through completion of the study \*The only recommended contraception is condoms. Exclusion Criteria: An individual who meets any of the following criteria will be excluded from participation in this study: 1. Any individual, or their legally authorized representative (LAR), who does not understand the requests and risks of participating in the clinical trial or is unable to give informed consent 2. Pregnancy or lactation 3. Prior cardiac surgery within the last 6 months 4. Hemodynamic instability as determined by the Principal Investigator 5. Immunosuppression 6. Active infections (e.g. HIV, Tbc, and all types of Hepatitis) 7. History of polycystic kidney disease 8. Patients with only one active kidney or one poorly functioning kidney 9. Evidence of current kidney obstruction (e.g., Kidney stones) 10. Evidence of current hydronephrosis 11. Active upper and/or lower urinary tract infections 12. Malignancy; oncological Surgery within 5 years or ongoing antitumoral treatment 13. Ongoing sepsis or endocarditis 14. Patients who have an expected 30-day postoperative mortality greater than 10% as determined by the Principal Investigator 15. Any secondary condition as determined by the investigator that would place the subject at an increased risk or preclude the subject's full compliance with the study procedures, including injuries to the urinary organs and/or external genitals; or severe BPH 16. Unexplained/unexpected gross hematuria as determined by the Investigator 17. Current or planned treatment with an investigational drug (IND), device (IDE), or other investigational intervention within 3 months prior to or during participation in this clinical trial 18. Patients who have a current unrepaired ureteral avulsion as determined by the investigator 19. Patients otherwise contraindicated for urological interventions, including ureter guidewire placement via bladder cystoscopy and ureteral catheterization, or otherwise contraindicated for any of the other study procedures