N-Acetylcysteine Does Not Prevent Contrast-Induced Nephropathy

N-Acetylcysteine Does Not Prevent Contrast-Induced Nephropathy: "N-Acetylcysteine Does Not Prevent Contrast-Induced Nephropathy
(Recommended by the AMICOR Paulo Caramori [caramori.p@plugin.com.br])

NEW YORK (Reuters Health) Jun 03 - N-acetylcysteine administration does not reduce the likelihood of contrast-induced nephropathy (CIN) after cardiac catheterization in patients at low to moderate risk of developing the complication, a new study shows.

CIN is a fairly common complication of cardiac procedures, Dr. Paulo Caramori of the Hospital Sao Lucas-PUCRS in Porto Alegre, Brazil, and colleagues note, and while hydration and use of low osmolality contrast media have been shown to help prevent it, the exact mechanisms at work remain unclear.

Based on the hypothesis that such injury is due to renal vasoconstriction and free radical release, the researchers set out to determine whether N-acetylcysteine, which has both vasodilating and antioxidant properties, might help prevent it. Past studies have shown conflicting results.

The researchers randomized 156 patients undergoing coronary procedures and considered to be at risk of developing CIN to 600 mg of N-acetylcysteine orally twice daily for 2 days or placebo, beginning the day before the procedure.

Patients were scheduled for coronary angiography or percutaneous coronary intervention, and all either had serum creatinine of 106.08 micromole/L or greater, creatinine clearance below 50 mL/ min or diabetes mellitus. Ionic low osmolality contrast medium was used in all patients.

CIN, defined as an increase of 44.2 micromoles/L in creatinine over a 48-hour period, occurred in 10.4% of the patients given N-acetylcysteine and 10.1% of those given placebo, which was not a significant difference, the researchers found.

'On the basis of these findings, we believe that the use of N-acetylcysteine in preventing CIN in patients undergoing cardiac catheterization should not be encouraged,' the researchers conclude.

'The recommended measures for preventing CIN continue to be appropriate hydration and the use of a small volume of contrast in patients at low to moderate risk of CIN undergoing cardiac catheterization with a low osmolality contrast medium.'

Heart 2005;91:774-778."