Extravascular perivenous fibrin support leads to aneurysmal degeneration and intimal hyperplasia in arterialized vein grafts in the rat

Abstract

Background and aims: External support of vein grafts by fibrin glue possibly prevents overdistension, vascular remodeling, and neointimal hyperplasia. Previous animal models of neointimal hyperplasia showed conflicting results. Here, long-term effects of external fibrin glue support were studied in a new rat model of jugular vein to abdominal aorta transposition. Materials and methods and methods: In male Wistar rats (250-300 g) right jugular vein (1.0-1.5 cm) was transposed to the infrarenal aorta. Fibrin glue (0.25 ml) covered the vein before releasing the vascular clamps (n∈=∈6). Control vein grafts were exposed directly to blood pressure. After 16 weeks vein grafts were pressure-fixed for histology. Intima thickness, luminal and intimal area were measured by planimetry and elastic fibers demonstrated by Elastica van Giesson staining. Results: Intimal thickness (74.04∈±∈6.7 μm vs 1245∈±∈187 μm, control vs fibrin treatment; p∈