Morphometric analysis of the intimal reaction after stent implantation in iliac arteries submitted to angioplasty in pigs1 Análise morfométrica da reação intimal secundária ao implante de stent em artérias ilíacas submetidas à angioplastia em suínos

Purpose: To compare through digital morphometry, the intimal thickening of the common ilíac arteries (CIA) in pigs, submitted to angioplasty and angioplasty followed by stent implantation. Methods: Angioplasty was performed in 10 pigs in both CIA, followed by a stent implantation in the left CIA. After four weeks, the aorto-iliac segment was dissected. Histologic slices where divided in three groups: left CIA in the area of the proximal (group 1) and distal (group 2) implantation site of the stent and the region of angioplasty in the right CIA (group 3). The histological slices were digitalized to be analyzed by morphometry with calculation of the luminal, intimal and media layers areas. Descriptive statistics analysis was performed through average and standard deviation of areas on each group, using ANOVA, with LSD Post-Hoc test (p≤0.05). Results: A significant statistic difference was observed when the median area of intimal layer of the groups 1 and 2 where compared with group 3 and in the media layer area of the groups 1 and 2 when compared with group 3. No difference was observed in luminal areas among the three groups. Conclusion: Angioplasty followed by stent insertion produces an intimal thickening larger than that observed after simple angioplasty. However, the area of the media layer is smaller in the “angioplasty plus stent” group and there is no significant change in the luminal area among the three groups.