Effectiveness of Biodegradable Magnesium Alloy Stents in Coronary Artery and Femoral Artery

Objectives: To access the biocompatibility, effectiveness, and safety of biodegradable magnesium (Mg) alloy stent (BMAS) in the coronary artery and femoral artery. Background: Atherosclerosis is a lesion of cardiovascular system, including the diseases in heart and blood vessels. Methods: The aluminum (Al) and zinc (Zn)-based BMAS was designed by cold drawing methods. Forty healthy immunized mongrel dogs were randomly divided into 8 groups. Five dogs who have not been treated with stent were included in control group. The other dogs were implanted with an absorbable magnesium (Mg) alloy in the coronary and/or femoral artery, and their artery angiography were observed at 7 time points (1, 3, 5, 7, 14, 21, and 28 days; n = 5) follow-up. Dogs from each cohort were sacrificed following angiography for pathology assessment. The histological response including inflammatory response, thrombosis, and intimal hyperplasia were analyzed by hematoxylin-eosin staining. Lumen area (La), intimal hyperplasia area (IHa), and the ratio of IHa were calculated by image analysis software. Results: The thin-walled BMAS were designed and produced by cold-drawing technology. Fifty-one devices were implanted into coronary artery of 35 dogs successfully. During the follow-up days, the angiography of coronary artery and femoral artery had confirmed that the lumen was clear and there were no elastic recoil and thrombosis. The stents were completely disappeared at 7 days after implantation. Moderate intimal hyperplasia was found at 14 days after implantation. Conclusion: The BMAS stent proved to be of good biocompatibility, safety, and effectiveness.