Evaluation of Renal Function in Subjects Who Had Undergone Cardiac Surgery

Study Overview
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Brief Summary
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To evaluate the differences between serum cystatin C based estimated glomerular filtration rate (eGFRcys), serum creatinine based eGFR (eGFRcreat) and measured glomerular filtration rate (mGFR) in subjects at high risk for acute kidney injury (AKI) approximately 90 days following cardiac surgery

Detailed Description
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This is an open label, single-visit study to evaluate the relationship between mGFR and eGFR based either on serum creatinine (eGFRcreat) or cystatin C (eGFRcys) approximately 90 days following cardiac surgery. No investigational study drug will be administered.

Official Title
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Evaluation of eGFR, Determined by Cystatin C and Creatinine, and mGFR, Measured by Iohexol Clearance, in Subjects at High Risk for Acute Kidney Injury (AKI) Following Cardiac Surgery

Conditions
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Cardiac Surgery

Intervention / Treatment
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* Diagnostic Test: mGFR by iohexol clearance


Participation Criteria
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Eligibility Criteria
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Key Inclusion Criteria: Male or female, age ≥ 45 years old At risk for AKI following cardiac surgery on the basis of at least one of the following pre-operatively assessed risk factors: Reduced renal function Diabetes with ongoing insulin treatment Albuminuria Have undergone non-emergent open chest cavity cardiovascular surgeries, with use of cardiopulmonary bypass (CPB), with or without hypothermic circulatory arrest Key Exclusion Criteria: Emergent surgeries, including aortic dissection, and major congenital heart defects Past cardiac surgery off CPB Have a known allergy to iohexol

Ages Eligible for Study
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Minimum Age: 45 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Male, BMI <= 24.9<br>Male subjects with a BMI of less than or equal to 24.9 | Diagnostic Test: mGFR by iohexol clearance<br>* Iohexol 5mL injection (300 mg iodine/mL) will be administered to all subjects to determine mGFR by iohexol clearance<br>|
| Female, BMI <= 24.9<br>Female subjects with a BMI of less than or equal to 24.9 | Diagnostic Test: mGFR by iohexol clearance<br>* Iohexol 5mL injection (300 mg iodine/mL) will be administered to all subjects to determine mGFR by iohexol clearance<br>|
| Male, BMI 25-29<br>Male subjects with a BMI of 25 to 29 | Diagnostic Test: mGFR by iohexol clearance<br>* Iohexol 5mL injection (300 mg iodine/mL) will be administered to all subjects to determine mGFR by iohexol clearance<br>|
| Female, BMI 25-29<br>Female subjects with a BMI of 25 to 29 | Diagnostic Test: mGFR by iohexol clearance<br>* Iohexol 5mL injection (300 mg iodine/mL) will be administered to all subjects to determine mGFR by iohexol clearance<br>|
| Male, BMI >29<br>Male subjects with a BMI of greater than 29 | Diagnostic Test: mGFR by iohexol clearance<br>* Iohexol 5mL injection (300 mg iodine/mL) will be administered to all subjects to determine mGFR by iohexol clearance<br>|
| Female, BMI >29<br>Female subjects with a BMI of greater than 29 | Diagnostic Test: mGFR by iohexol clearance<br>* Iohexol 5mL injection (300 mg iodine/mL) will be administered to all subjects to determine mGFR by iohexol clearance<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation between eGFR and mGFR | The primary measure will be the comparison of the P(30) and P(10) between eGFR based on serum cystatin C (eGFRcys) and eGFR based on serum creatinine (eGFRcreat). P(30) and P(10) are defined as the percentage of subjects whose eGFR is within 30% (10%) of the iohexol-based mGFR. | at 90 days post cardiac surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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GFR, Acute Kidney Injury, AKI