IC:How do you appraise the advantages and disadvantages of Corevalve system and Edwards system in TAVI?
　　Dr. Applegate: At Wake Forrest， we have done 33 CoreValve replacements， so I am aware of the some of the issues related to the CoreValve. We are going to begin using the SAPIEN system soon. Let us first talk about the valves themselves. First of all， we know the SAPIEN valve is expandable and there are two sizes， the 23 and the 26. In addition， it requires precise measurement of the annulus of the patient to match the valve size. If not careful， a very small valve could be put in a large annulus. It would be ejected out of that position if not held in place by the stent struts and the patient’s own aortic valve anatomy. For the CoreValve， it is a self-expanding stent. Because of that， there are two important and relevant differences with the SAPIEN valve. Once you expand the SAPIEN valve， it is locked in position and will have to be dealt with accordingly if complications arise. Meanwhile， the CoreVlave is still attached to the delivery device while it is functioning. It is then placed in the aortic valve position so that， in case of a high deployment above the annulus， one can retrieve it through the sheath and replace it with another valve. With the CoreVlave， there is some term of repositionability during the procedure itself and slight movement that can occur. Also， because it is a self-expanding stent， we have noticed in the vasculature， for example in iliac or carotid， there is a range of sizing that you achieve with the stent valve itself in relation to the annulus. This means there is a little more flexibility in terms of the placement. That is number one.
　　《国际循环》：你如何评价Corevalve系统和Edwards系统在TAVI中应用的优势和劣势？
　　Applegate教授：我们在Wake Forrest中心已经开展了33例Corevalve主动脉瓣置换术，所以我了解Corevalve的一些相关情况。很快我们要开始应用SAPIEN系统。我们先来谈谈瓣膜本身。首先，我们知道SAPIEN瓣膜是可膨胀式瓣膜，有23和26两个型号。另外，需要精确测量瓣环，使瓣膜型号与其相匹配。如果不仔细，可能给大的瓣环植入了一个非常小的瓣膜。如果支架支撑杆和患者自身的主动脉瓣解剖学情况无法将植入的瓣膜固定，瓣膜可从植入部位弹出。CoreValve似乎一个自膨式支架，因而与SAPIEN瓣膜有两个重要的且有临床意义的区别。一旦SAPIEN膨胀之后，就被锁定在植入部位，如果发生并发症，需进行相应处理。CoreVlave还是与输送装置相连，输送装置仍在发挥作用。随后，CoreVlave被植入主动脉瓣的位置，如果在瓣环较高位置释放，通过输送导管移除瓣膜并用另一个瓣膜来替换它。对于CoreVlave来说，操作过程中从某种程度上可重新放置瓣膜，也会发生轻微的移动。另外，由于CoreVlave是自膨式支架，因此我们注意到在血管床（例如髂血管或颈部血管），支架瓣膜本身还可以形成一定范围内的距离，与瓣环相对应。这意味着放置时更有灵活性。