Bai Yuan, Zong Gang-Jun, Wang Yan-Yan, Jiang Hai-Bin, Li Wei-Ping, Wu Hong, Zhao Xian-Xian, Qin Yong-Wen
Department of Cardiology, Changhai Hospital, Second Military Medical University, Shanghai 200433, China.
Chin Med J (Engl). 2009 Mar 20;122(6):655-8.
Percutaneous aortic valve replacement is a promising strategy in the treatment of patients with aortic valve stenosis. And many kinds of valved stents have been implanted in selected patients worldwide. However, the clinical experience is still limited. We developed a W-model valved stent and evaluated the feasibility and safety of percutaneous implantation of the device in the native aortic valve position.
A self expanding nitinol stent with W-model, containing porcine pericardium valves in its proximal part, was implanted in six sheep by means of a 14 French catheter through the right common iliac artery under guidance of fluoroscopy. During stent deployment the original aortic valve was pushed against the aortic wall by the self expanding force of the stent while the new valve was expanded. These sheep were followed up shortly after procedure with supra-aortic angiogram and left ventriculography. Additionally, one sheep was sacrificed after the procedure for anatomic evaluation.
It was possible to replace the aortic valve in the beating heart in four sheep. The procedure failed in two sheep due to coronary orifice occlusion in one case and severe aortic valve regurgitation in the other case. One sheep was killed one hour after percutaneous aortic valve replacement for anatomic evaluation. There were no signs of damage of the aortic intima, or of obstruction of the coronary orifice.
Percutaneous aortic valve replacement with a W-model valved stent in the beating heart is possible. Further studies are mandatory to assess safety and efficacy of this kind of valved stent in larger sample size and by longer follow-up period.
经皮主动脉瓣置换术是治疗主动脉瓣狭窄患者的一种有前景的策略。在全球范围内，多种带瓣支架已被植入选定的患者体内。然而，临床经验仍然有限。我们研发了一种W型带瓣支架，并评估了将该装置经皮植入天然主动脉瓣位置的可行性和安全性。
一种带有W型的自膨胀镍钛合金支架，其近端包含猪心包瓣膜，在透视引导下通过一根14F导管经右髂总动脉植入6只绵羊体内。在支架展开过程中，原主动脉瓣被支架的自膨胀力推向主动脉壁，同时新瓣膜展开。术后不久对这些绵羊进行主动脉弓上血管造影和左心室造影随访。此外，术后处死1只绵羊进行解剖评估。
4只绵羊在心脏跳动时成功置换了主动脉瓣。2只绵羊手术失败，1例因冠状动脉口阻塞，另1例因严重主动脉瓣反流。1只绵羊在经皮主动脉瓣置换术后1小时处死进行解剖评估。未发现主动脉内膜损伤或冠状动脉口阻塞的迹象。
在心脏跳动时用W型带瓣支架进行经皮主动脉瓣置换是可行的。必须进行进一步研究，以更大样本量和更长随访期评估这种带瓣支架的安全性和有效性。
