Design and preparation of medical polyester-coated nitinol ventricular septal defect occluder / 第二军医大学学报

ABSTRACT

Objective To design and prepare a polyester-coated nitinol ventricular septal defect (VSD) occluder. Methods The shape wax model was made by slightly stretching the shape of the commercially available nitinol VSD occluder. The wax model was fixed on the weaving machine and a wax model-polyester coat compomer was made using the medical 4-0 sutures by warp knitting method. Then dewaxing and defatting were done and the polyester coat was produced. The commercially available nitinol VSD occluder was placed into the coat by sheath, with the ends of the polyester coat sutured at the VSD stainless steel rivets, and the surplus parts of both ends were cut by hightemperature knife. Results The polyester coat of VSD occluder was successfully made by weaving machine and warp knitting method. Polyester coat had a waist diameter of 8 mm and a disc diameter of 12 mm, and it completely fit with the conventional nitinol VSD occluder with diameter being 8 mm. The polyester coat was sutured tightly with the VSD occluder, and the surplus parts of two ends of the VSD occluder were cut smooth by high-temperature knife, with no loosening of the wire. Conclusion The polyester coat of nitinol VSD occluder can be woven by the weaving machine and warp knitting method, and then the polyester-coated nitinol VSD occluder can be successfully made by suture and high-temperature cutting.