The renal effect of low-dose dopamine in high-risk patients undergoing coronary angiography

OBJECTIVES The purpose of the study was to examine the potential renal protective effect of low-dose dopamine in high-risk patients undergoing coronary angiography. BACKGROUND Contrast nephropathy is prevalent in patients with chronic renal failure (CRF) and/or diabetes mellitus (DM). Decreased renal blood flow due to vasoconstriction was suggested as a contributory mechanism. Low-dose dopamine has a dilatory effect on the renal vasculature. METHODS Sixty-six patients with mild or moderate CRF and/or DM undergoing coronary angiography were prospectively double-blindedly randomized, to either 120 ml/day of 0.9% saline plus dopamine 2 mu g/kg/min (Dopamine group) or saline alone (Control group) for 48 h. RESULTS Thirty-three Dopamine-treated (30 diabetics and 6 with CRF) and 33 Control (28 diabetics and 5 with CRF) patients were compared. Plasma creatinine (Cr) level increased in the Control group from 100.6 +/- 5.2 before to 112.3 +/- 8.0 mu mol/liter within five days after angiography (p = 0.003), and in the Dopamine group from 100.3 +/- 5.4 before to 117.5 +/- 8.8 mu mol/liter after angiography (p = 0.0001), respectively. There was no significant difference in the change of Cr level (Delta Cr) between the two groups. However, in a subgroup of patients with peripheral vascular disease (PVD), Delta Cr was -2.4 +/- 2.3 in the Control group and 30.0 +/- 12.0 mu mol/liter in the Dopamine group (p = 0.01). No significant difference occurred in Delta Cr between Control and Dopamine in subgroups of patients with preangiographic CRF or DM. CONCLUSTIONS Contrast material caused a small but significant increase in Cr blood la el in high-risk patients. There is no advantage of dopamine over adequate hydration in patients with mild to moderate renal failure or DM undergoing coronary angiography. Dopamine should be avoided in patients with PVD exposed to contrast medium. (C) 1999 by the American College of Cardiology.