Macroscopic and histological analysis of the vascular wall after implantation of a self-expanding nitinol stent: results of a preclinical in vivo study

Objective. To perform macroscopic and histological analysis of the vascular wall after implantation of a self-expanding nitinol stent in the in vivo experiment. Material and methods. 2 Danish Landrace pigs were selected for experimental implantation of a new self-expanding nitinol stent with an oversizing of 5–20%. Vital signs were assessed in both pigs throughout the observation period. In the postoperative period, both animals received dual antiplatelet therapy for 3 months. After 3 months, the animals underwent control angiography and ultrasound examination of the iliofemoral segment, followed by withdrawal from the experiment by euthanasia. The next step was a morphological analysis of the stented areas of the vessels. Results. The observation period of the animals was 3 months. Throughout the entire observation period, vital signs in both animals remained within normal values. Control angiography and ultrasound examination after 3 months demonstrated patency and the absence of significant restenoses in both pigs. Morphological analysis showed no signs of damage to the vessel walls. Conclusion. This study showed a favorable response of the animal's body to the implantation of the presented self-expanding nitinol stent with minimal neointimal hyperplasia from the inner wall of the common iliac artery in the postoperative period.