Study on transcatheter ASD occlusion using modified atrial septal defect occluder with no stainless steel screw in canine model / 介入放射学杂志

ABSTRACT

Objective To evaluate the safety,biocompatibility and efficacy of transcatheter closure of atrial septal defect(ASD)with no stainless-steel-screw occluder in canine model.Methods The device was constructed from superelastic Nitinol wires tightly woven into two flat disks and sewed with polyester fibers inside,with a pliable loop on the right-atrial-disk of the device,connecting to the delivery cable.ASD was created by transcatheter puncture and balloon dilatation and then closed by occluder under fluoroscopy in the catheterization laboratory.The location and the influence of the implanted device on function of tricuspid valve and mitral valve were evaluated by echocardiography.At 1,2,3 and 6 months after the operation,the animals were killed and autopsy was conducted.Results Eight dogs with puncture-produced ASD underwent ASD closing procedure successfully.The occluder showed no influence on the function of MV and AV demonstrated by echocardiogram.The two disks of the implanted device were covered with a smooth intact neogenesis layer in all dogs.Endocardial cells fully covered the surface of the two disk without inflammating reaction 3 months later. There was no evidence of corrosion on the surface of the nitinol wire removed from the dog after 6 months.Light microscopic examination of the liver,kidney,lung and spleen showed no evidence of embolization and inflammation.Conclusion Transcatheter ASD occlusion with new-type occluder is safe,feasible,effective and good biocompatibility with a good prospective clinical application.