Exogenous Fibronectin to Prevent Neointimal Hyperplasia after Balloon Angioplasty

This study examined the effect of fibronectin to prevent restenosis in a microswine model after balloon angioplasty of the right iliac artery. Immediately following angioplasty, fourteen hypercholesterolemic microswines were randomized to receive fibronectin (223.5 mg, n = 8) or saline containing albumin (75.6 mg, n = 6). At 60-days post-angioplasty, the angioplasty-injured and intact contralateral arteries were examined with angiography and histopathology. With angiography, there was no significant difference in the luminal diameters of angioplasty arteries compared with the intact contralateral vessels. Histological examination of angioplasty-injured vessels showed neointimal hyperplasia. The intimal areas of angioplasty-injured vessels, in the placebo and fibronectin groups, were much larger than the areas of their contralateral vessels (fibronectin 287 +/- 160 vs. 138 +/- 88 µm2, p = 0.018; and the placebo (1,245 +/- 1,567 vs. 248 +/- 219 µm2, p = 0.041). Mean total cholesterol levels of both groups were maintained at levels > 400 mg/dl throughout the study period. CONCLUSION: At sixty days after balloon angioplasty injury: 1) fibronectin did not only not prevent neointimal hyperplasia, in some animals, it increased neointimal growth; and 2) angiographic results were not sensitive enough to quantify changes observed in histologic findings.