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 prot ective effect of low-dose dopamine in high-risk patients undergoing coronar y angiography. BACKGROUND Contrast nephropathy is prevalent in patients with chronic renal failure (CRF) and/or diabetes mellitus (DM). Decreased renal blood flow du e to vasoconstriction was suggested as a contributory mechanism. Low-dose d opamine has a dilatory effect on the renal vasculature. METHODS Sixty-six patients with mild or moderate CRF and/or DM undergoing c oronary angiography were prospectively double-blindedly randomized, to eith er 120 ml/day of 0.9% saline plus dopamine 2 mu g/kg/min (Dopamine group) o r 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 creati nine (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 mo l/liter after angiography (p = 0.0001), respectively. There was no signific ant 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/li ter in the Dopamine group (p = 0.01). No significant difference occurred in Delta Cr between Control and Dopamine in subgroups of patients with preang iographic CRF or DM. CONCLUSTIONS Contrast material caused a small but significant increase in C r 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 u ndergoing coronary angiography. Dopamine should be avoided in patients with PVD exposed to contrast medium. (C) 1999 by the American College of Cardio logy.