Stainless steel/nitinol braid coronary stents: Braiding structure stability and cut section treatment evaluation

Abstract

This study proposes braid coronary stents with a form of reticular tube by using a braiding technique. Stainless steel fibers with a diameter of 0.08 mm and nitinol fibers are braided with various tooth numbers on the take-up gear and a specified tooth number on the braid gear with a hollow braiding technique in order to have different braiding angles. The resulting braids are then immersed in a polyvinyl alcohol solution in a custom-made mold to form braid coronary stents. A stereomicroscope is used to observe the cut section, a scanning electron microscope is used to examine the treatment for sharp points of the fibers, and Image Pro Plus software is used to analyze braiding angles and metal cover rate. The experiment results show that braiding angle influences the braiding structure; in addition, the larger the braiding angle, the less easily the fiber interaction points move. The immersion in polyvinyl alcohol solution can effectively bond the fiber interaction points, resulting in a better braiding structure. Metal cover rates are all below 20.9%. This study successfully creates novel braid coronary stents.