Damage effect of Solitaire stent on tunica intima during thrombectomy

Objective To discuss the damage effect of Solitaire stent on tunica intima during thrombectomy, so as to evaluate the safety of thrombectomy. Methods Twelve healthy male New Zealand rabbits were randomly divided into 4 groups (3 rabbits in each group), including control group and 3 thrombectomy groups. Microcatheter was used instead of stent in control group. The other 3 groups underwent mimic thrombectomy for 1, 3 and 5 times in the same position, respectively. The procedure was performed at both sides of carotid artery of each rabbit. Immediately after operation, bilateral carotid arteries of each rabbit were removed, performed HE staining and examined the ultrastructure under microscope. Semi?quantitative analysis was used to evaluate the damage of carotid artery.  Results During the model preparation, DSA showed the diameter of vascular wall was 2.10-2.90 mm, and there was no vascular spasm, bleeding, perforation or arterial dissection. Therefore, the model was successfully established. The difference of carotid artery damage among different groups was statistically significant ( F = 119.108, P = 0.000). Compared with control group, the carotid artery damage of 3 thrombectomy groups was more serious ( q = 3.136,  P = 0.001;  q = 7.463,  P = 0.000;  q = 10.682,  P = 0.000). The carotid artery damage of the second and third thrombectomy group was more serious than the first group ( q = 3.330,  P = 0.000;  q = 8.160,  P = 0.000). The carotid artery damage of the third thrombectomy group was more serious than the second group ( q = 4.830,  P = 0.000). Optical microscope observation showed that with the increase of times of thrombectomy, carotid intimal injury was more extensive and intimal reaction was more severe. Scanning electron microscopy showed that with the increase of times of thrombectomy, the degree of carotid artery injury was increased.  Conclusions Solitaire stent may injure tunica intima, and with the increase of times of thrombectomy, the damage to vascular wall will increase. DOI: 10.3969/j.issn.1672-6731.2017.11.008