Robert J. Applegate：美国韦克福雷斯特大学医学中心医学博士。擅长心血管病和介入心脏病学。在药物洗脱支架PCI和裸金属支架PCI以及新方法上著作卓著。
　　IC:When do you think TAVI is indicated? How should physicians use it?
　　Dr. Applegate: Right now， the standard of care for treatment of aortic stenosis is surgery， as it has both well-established and outstanding immediate and long term results. However， TAVI is a therapy for patients that have severe aortic stenosis. This is a bit of a challenge， because trial definitions from PARTNER and CoreValve insist on very severe aortic stenosis， defined as 0.8 cm2 or less with gradients. This is opposed to the ACC/AHA guidelines， which suggest that it be less than 1.0 cm2. There are different manifestations of severe aortic stenosis， some of which depend on the ability to generate enough stroke volume to have a high gradient. However， some patients with severe aortic stenosis are not able to generate that gradient and are identified only by using echocardiography or planimetry of the valve area. One of the issues surrounding the treatment of aortic stenosis prior to TAVI was that patients with severe aortic stenosis had shorter life spans， independent of their symptoms. TAVI is by far and away the indication for severe aortic stenosis.
　　《国际循环》：您认为TAVI的适应证是什么？医生应当如何应用TAVI？
　　Applegate教授：当前，主动脉瓣狭窄的标准治疗是外科手术，因为外科手术是明确的治疗手段，同时有不错的近期和远期效果。而TAVI是适合重度主动脉瓣狭窄患者的治疗方法。它面临一些挑战，因为PARTNER和CoreValve试验中对重度主动脉瓣狭窄的定义是有跨瓣压差时瓣口面积≤0.8 cm2。这与ACC/AHA指南不符，该指南指出，重度主动脉瓣狭窄的定义是瓣口面积< 1.0 cm2。重度主动脉瓣狭窄的表现多种多样，其中一些表现取决于产生足够的每搏输出量以产生高的跨瓣压差。但是，一些重度主动脉瓣狭窄患者不能产生该跨瓣压差。因此，只有在采用心脏超声测量瓣膜口面积时才能被发现。在TAVR出现之前，重度主动脉瓣狭窄治疗的问题之一是患者的寿命短，其寿命与症状无关。毫无疑问，重度主动脉瓣狭窄是TAVI的适应证。