CIN and its prevention continue to be an area of intense research and, at the same time, of controversy due to conflicting results from different studies, including this one.
Contrast-induced nephropathy (CIN) is a well-recognized complication of iodinated contrast exposure. The incidence ranges from 2% to 50%. Prior studies have shown a beneficial effect of hydration with either sodium chloride or sodium bicarbonate administered before and after the procedure.
The MEENA trial assessed whether sodium bicarbonate is superior to sodium chloride and its impact on mortality.
The single-center, randomized, controlled study was performed between January 2006 and January 2007. Prior to catheterization, patients were randomized in 1:1 blocks of 4 and stratified by diabetes and N-acetylcysteine status. Patients were treated with either sodium chloride 0.9% saline or sodium bicarbonate 150 mEq in D5W and underwent coronary angiography. To be included in the study, the calculated glomerular filtration rate (GFR) had to be ≤ 60 mL/minute/1.73 m2, and the patient needed to have at least 1 of the following risk factors: diabetes, congestive heart failure, hypertension, or age > 75 years. Serum creatinine was obtained within 4 days.
Primary endpoint: CIN, defined as a ≥ 25% reduction in GFR within 4 days.
A ≥ 25% increase in serum creatinine;
30-day de novo dialysis;
30-day all-cause mortality; and
GFR at 2-8 weeks post procedure.
A total of 353 patients were randomized to receive either sodium chloride (n = 178) or sodium bicarbonate (n = 175); 50 patients were excluded from the analysis. Baseline characteristics were well balanced between the 2 groups ( Table ). In addition, the proportion of patients with baseline severe kidney dysfunction (eGFR ≤ 30) and the average contrast volume were similar in both study arms.
In both patient groups, the incidence of CIN was approximately 14%, and there was no difference in the percentage of patients with an increase of ≥ 25% of serum creatinine between the 2 groups (Figure). At 2-8 weeks following the procedure, 37% of patients in the sodium chloride arm had a GFR drop ≥ 15% vs 58% in the sodium bicarbonate group. There were 5 deaths in the study, 2 in the sodium chloride and 3 in the sodium bicarbonate arm (1.3% vs 2%, P = NS). Only 1 patient required dialysis in the sodium chloride group (0.7% at 30 days).
The incidence of dialysis was low.
Mortality at 30 days was not significantly different between the 2 groups.
Among patients with CIN, 47% failed to recover to baseline renal function by 208 weeks.
Hydration with sodium chloride or sodium bicarbonate in patients undergoing coronary angiography with a GFR of ≤ 60 resulted in very similar rates of CIN.
CIN and its prevention continue to be an area of intense research and, at the same time, of controversy due to conflicting results from different studies, including this one. The MEENA trial looked at 2 methods of hydration prior to coronary angiography, with results that are discordant with the recently published results of the Renal Insufficiency Following Contrast Media Administration Trial (REMEDIAL) trial. According to the present study, 0.9% saline hydration was similar to sodium bicarbonate for the prevention of CIN, whereas in the REMEDIAL trial, sodium bicarbonate was superior to normal saline alone in preventing CIN.
Medscape Cardiology © 2007 Medscape
Cite this: MEENA: Prevention of Contrast-Induced Nephropathy With Sodium Bicarbonate in Persons Undergoing Coronary Angiography - Medscape - Apr 26, 2007.