Contrast Nephropathy and Nitrates (CoNaN)

Contrast-induced nephropathy (CIN) is a complication of percutaneous coronary angiography that occurs in about 10 to 20% of patients exposed to contrast media. Iodinated contrast is used during coronary angiography to see the coronary arteries. It has been shown that exposure to this agent may cause kidney injury. CIN usually goes away on its own but in some high risk patients it progresses into renal failure. This research study offers a new possible option to prevent CIN. We propose that if intravenous nitroglycerin is given before the procedure it may lower the chances of developing contrast-induced nephropathy.

The Contrast Nephropathy and Nitrates trial (CoNaN) is a single center, randomized, 1 x 1 factorial clinical trial designed to test the effects of intravenous nitroglycerin infusion in renal function given prior to PCI. Specific aims for this trial include: To determine whether the intravenous nitrates have any effect on the glomerular filtration rate (GFR) after the exposure to contrast media. To determine if intravenous nitroglycerin will decrease the incidence of contrast induced Nephropathy. 400 patients with a Mehran score of > 6 and a pre-procedural creatinine measurement will be enrolled. Following baseline assessments, patients will be randomly assigned to receive intravenous infusion nitroglycerine plus intravenous normal saline or normal saline only. Subjects will participate in this study from the time they sign consent (prior to angiographic procedure), until 48-72 hours post procedure.

The primary endpoint for this trial will be to determine the change in glomerular filtration rate after exposure to contrast media. We will compare the change in GFR before and after PCI of the group that received intravenous nitroglycerin with the change in GFR before and after PCI of the group that did not receive intravenous nitroglycerin.

Inclusion Criteria: Patient must be scheduled for percutaneous coronary angiography. Patients must have a Mehran score more or equal to 6 before the procedure. Patients must have baseline creatinine and hemoblogin drawn before the procedure. Signed informed consent. Exclusion Criteria: Patients on renal replacement therapy before randomization, will be excluded. Being exposed to any types of nitrates 48 hours prior to randomization, History of allergic reaction to any of the components of intravenous nitroglycerin. Exposure to contrast media 4 days prior randomization. Planned revascularization in the next 24 to 48 hours of the first PCI procedure. The patient is hypotensive (<90/60mmHg) at the time of randomization.