No difference among modern contrast media's effect on neointimal proliferation and restenosis after coronary stenting in pigs

Rationale and Objectives: Recent clinical trials indicate that the choice of radiographic contrast media (CM) may influence the late outcome of coronary interventions. This might be explained by the different effects of various CM on neointimal proliferation. Methods: The effect of a 1-hour incubation of bovine aortic smooth muscle cells in ioxaglate or iopromide solution on in vitro cell division was tested. Furthermore, in 12 pigs randomized into 3 groups (iopromide, ioxaglate, and iosimenol; a novel nonionic dimer), coronary angiography was performed followed by implantation of stents. After 28 days, restenosis was assessed by quantitative angiography and histomorphometry. Results: Compared with saline, CM did no change cell counts up to 15 days after incubation. Baseline parameters in the pigs indicated no difference between the test groups. After 28 days, the test groups showed no significant differences in the parameters characterizing in-stent restenosis. Conclusions: Under the experimental conditions iopromide, ioxaglate, and iosimenol had no or very similar direct or otherwise mediated effect on cell proliferation and restenosis.