The effect of oversized occluder on endothelialization after percutaneous closure of experimental atrial septal defect in dogs / 中华心血管病杂志

ABSTRACT

<p><b>OBJECTIVE</b>To observe the effect of oversized occluder on endothelialization post percutaneous closure of experimental atrial septal defect (ASD) in dogs.</p><p><b>METHODS</b>ASD was established with the help of transthoracic echocardiography in 18 dogs. ASD size was (6.0 ± 0.2) mm. Dogs were randomly divided into normal size group (implanted with 8 mm occlude, n = 9) and oversized group (implanted with 12 mm occluder, n = 9). Dogs were randomly killed at 3, 6 and 14 months after percutaneous closure. The endothelialization process on device surface was observed by scanning electron microscope.</p><p><b>RESULTS</b>Four animals died around 1 month post procedure. Microscopic sections from normal group showed nearly complete endothelialization at 3 months after device implantation and complete endothelialization at 6 and 14 months after device implantation. While microscopic sections showed lack of endothelialization at 3 months post implantation, nearly endothelialization at 6 months, and complete endothelialization at 14 months after device implantation in oversized group.</p><p><b>CONCLUSION</b>Incomplete endothelialization of occluder surface is observed at 6 months after implantation of an oversized ASD occluder device in this model.</p>