A randomized trial comparing the impact of a nonionic (iomeprol) versus an ionic (ioxaglate) low osmolar contrast medium on abrupt vessel closure and ischemic complications after coronary angioplasty

OBJECTIVES To assess the effect of nonionic versus ionic contrast media on abrupt vessel closure and major ischemic complications after coronary angioplasty. BACKGROUND There is a continuous debate about the "thrombogenic potential" of nonionic contrast media. The results of both in vitro and in vivo investigations are incongruent. METHODS We prospectively evaluated the outcomes of 2,000 patients undergoing percutaneous transluminal coronary angioplasty (PTCA). According to a randomized, double-blind protocol, they received either iomeprol (nonionic; n = 1,001) or ioxaglate (ionic; n = 999). Intracoronary thrombus before PTCA was found more often in the iomeprol group (4.2% vs 2.7%, p = 0.04). No other significant differences between both groups were observed with regard to pre-PTCA clinical and angiographic characteristics. RESULTS The frequency of reocclusions necessitating repeat angioplasty occurring either in laboratory (2.9% with iomeprol and 3.0% with ioxaglate) or out of laboratory (3.1% vs 4.1%) was not significantly different. The rate of major ischemic complications was also comparable aft er both contrast media (emergency bypass surgery: 0.8% vs 0.7%, myocardial infarction: 1.8 vs 2.0%, cardiac death during hospital stay: 0.2% vs 0.2%). In the iomeprol group, more patients had dissections post-PTCA (30.2% vs 25.0%, p = 0.01) and more patients received intracoronary stents (31.6% vs 25.7%, p = 0.004). Allergic reactions requiring treatment occurred only in the ioxaglate group (0.0% vs 0.9%, p = 0.002). CONCLUSIONS The nonionic contrast medium was not associated with a higher rate of abrupt vessel closure requiring repeat angioplasty, or major ischemic events. These data suggest that nonionic contrast media do not increase the risk of thrombotic complications in patients undergoing coronary interventions. (C) 1999 by the American College of Cardiology.