Influence of the arterial elastic component on the response to balloon angioplasty in femoral arteries of a healthy porcine model

BACKGROUND: The efficacy of balloon angioplasty for treating peripheral artery disease is influenced by various factors, some of them not yet totally understood. This study aimed to evaluate the role of elastin content in vascular responses 28 days post-angioplasty using uncoated and paclitaxel-coated balloons with the same platform in femoral arteries of a healthy porcine model. METHODS: Eight animals underwent balloon angioplasty on the external and internal branches of femoral arteries. Histopathologic evaluation was conducted at follow-up to assess the elastin content, vascular damage, morphological features, and neointimal formation. RESULTS: The elastin content was significantly higher in the external than in the internal femoral artery (p = 0.0014). After balloon angioplasty, it was inversely correlated with vascular injury score (ρ = -0.4510, p = 0.0096), neointimal inflammation (ρ = -0.3352, p = 0.0607), transmural (ρ = -0.4474, p = 0.0103) and circumferential (ρ = -0.4591, p = 0.0082) smooth muscle cell loss, presence of proteoglycans (ρ = -0.5172, p = 0.0024), fibrin deposition (ρ = -0.3496, p = 0.0499), and adventitial fibrosis (ρ = -0.6229, p = 0.0002). Neointimal formation inhibition with paclitaxel was evident only in arteries with disruption of the internal elastic lamina, with a significant smaller neointimal area in arteries treated with paclitaxel-coated balloons compared to uncoated balloons (median [Q1-Q3]: 10.25 [7.49-15.64] vs. 24.44 [18.96-30.52], p = 0.0434). CONCLUSIONS: Elastin content varies between branches of the femoral artery and significantly influences the integrity of the internal elastic lamina, the vessel's adaptive response, and paclitaxel efficacy after balloon angioplasty.