The degradation time and the intimal hyperplasia of biodegradable magnesium alloy stent implanted in the abdominal aorta of experimental rabbits / 介入放射学杂志

ABSTRACT

Objective To observe the degradation time and the intimal hyperplasia of biodegradable magnesium alloy stent (MPM) implanted in the abdominal aorta of experimental rabbits.Methods A total of 24 New Zealand white rabbits were randomly divided into four groups (30 d,60 d,90 d and 180 d) with 6 rabbits in each group.In cach rabbit one MPM stent was implanted in the abdominal aorta at the level of one cm below the left renal artery.Reexamination of abdominal aortography with DSA was separately performed at 30,60,90 and 180 d after stent implantation to check the stent condition.The rabbits of each group were sacrificed at the corresponding scheduled day,the stenting segment of aorta of each rabbit was removed and the specimen was sent for microscopic examination.The experimental results were analyzed with SPSS20.0 software.Results All the 24 experimental rabbits survived.During the follow-up period the stent showed gradual degradation changes,and basically complete degradation was not observed until to 180 days.Meanwhile,the intimal hyperplasia reached its peak at 90 days after implantation.The abdominal aorta remained unobstructed during the whole process of degradation.Conclusion The time of complete degradation for MPM stent is 182 days,which is long enough to meet the needs of vascular positive remodeling.