Inorganic Nitrate (NaNO3) Prevention of Contrast-Associated Acute Kidney Injury

The study drug is sodium nitrate capsule at a dose of 12mmol of nitrate. This medication will be given orally 1-8 hours before the planned contrast administration and then once per day for a total of four doses.

The placebo control medication will be a capsule filled with lactose that will be taken in the same manner and schedule as the sodium nitrate capsule