Contrast-Induced Nephropathy (CIN) can occur when patients with pre-existing kidney problems undergo procedures that use iodinated contrast media, such as cardiac catheterizations. RenalGuard Therapy was developed to enable the patient to clear the contrast out of their kidney before it can do significant damage. This study aims to enroll patients with increased risk of developing CIN who are scheduled for a cardiovascular catheterization. Patients will be randomized to either RenalGuard therapy or standard therapy.

Inclusion Criteria:

• Male or non-pregnant female equal or greater than the age of 18 years old and is able to provide informed consent.
• Subject is scheduled to undergo an elective catheterization procedure
• Hemodynamically stable
• At increased risk of developing CIN
• Subject has agreed to all follow-up testing.

Exclusion Criteria:

• Class 4 Congestive Heart Failure (CHF)or a documented left ventricular ejection fraction < 30%
• Is anuric or has undergone renal replacement therapy within the past month, or has a known inability to have a Foley catheter placed.
• Subject has been hospitalized or treated medically for any change in renal function over the past week (i.e. dialysis, etc.), or a significant change in renal function is noted at time of screening.
• Has documented severe Aortic Stenosis.(Note: Subjects who have undergone successful replacement or repair of their aortic valve are not excluded.)
• Currently has a known clinically significant electrolyte imbalance or clinically significant arrhythmias which compromise subject's hemodynamic state.
• Patient has severe anemia (hemoglobin < 8.0 g/dL) at screening
• Has received contrast within 10 days of procedure or has a planned additional cardiac or renal or other major surgical procedure within the 7 day follow-up period.
• Has ruled in for a Serious Heart Attack within 48 hours of the planned procedure
• Has documented respiratory insufficiency as evidenced by an oxygen saturation of < 90% on room air assessed on day of procedure.
• Planned addition, discontinuation or dose adjustment of nephrotoxic drugs
• Subject has a known hypersensitivity to furosemide and/or the contrast agent being used.
• Subject is currently, plans, or has been enrolled in another clinical study involving use of an investigational drug or device within the prior 30 days.
• Subject is pregnant or breastfeeding.
• Subject is unable to provide informed consent.