International Circulation：The accurate assessment of the haemodynamic severity of stenosis is crucial for clinical decision making in patients with aortic stenosis. Over the past decades， echocardiography has become the clinical standard for the evaluation of aortic stenosis severity. Several indices have been used for this purpose including transvalvular velocity and gradient， aortic valve area， valvular resistance， left ventricular stroke work loss and the energy loss coefficient. Could you tell us how to assess the severity of aortic stenosis accurately? And which one is the most important?

《国际循环》：准确评估主动脉狭窄血流动力学的严重性对于制订临床治疗决策至关重要的。在过去的几十年，超声心动已经成为评价主动脉狭窄严重程度的标准。跨瓣血流速度和压力阶差、主动脉瓣口面积、瓣膜阻力、左心室搏出功损耗、能量损失等几个指标常用来评估主动脉狭窄的严重性。您能说一下怎样准确评估吗？哪一项指标最重要？

Prof. Helmut Baumgartner :We have just reviewed carefully all echocardiographic techniques with all parameters so far proposed for the classification of aortic stenosis because we are about to finish our recommendations， joint European and American recommendations for the assessment of valvular stenosis and particularly aortic stenosis. Now what we finally came up with is that it is still the most robust and the best way to evaluate valvular stenosis by reporting a composite of peak transvalvular velocity， mean gradient and continuity equation valve area. From a pathophysiological point of view there may indeed be superior parameters such as the energy loss coefficient because this parameter would taking into account in some patients that maybe significant pressure recovery， particularly in the case of  a smaller aorta. What really matters from a pathophysiological point of view is the load to the left ventricle and this would for example be probably better reported by energy loss coefficient. On the other hand， one has to keep in mind that as more complex a variable gets as more errors we put into these equations. Looking at the energy loss coefficient， you need the transvalvular velocity， you need the valvular area， you need the area of ascending aorta. Unfortunately some error is unavoidable for each of these measurements in vivo and this then multiplied. It’s unrealistic to be absolutely precise with such a calculated number. It is probably much more important to be really aware of the limitations of each of the measurements， what are the sources of error for the gradient measurement， what are the sources of error for the valve area. For the final decision of how to judge a stenosis， we should then take all the information together: the morphology of the valve， the transvalvular velocity and gradient， the calculated valve area， left ventricular function and individual flow conditions. And of course we need to look at the symptoms of our patient for the final decision whether to operate on.

Helmut Baumgartner 教授：不久前我们全面回顾了各种超声心动技术下与主动脉瓣狭窄分级相关的参数，目的是结合美国和欧洲的诊疗建议，完成我们对瓣膜狭窄，尤其是主动脉瓣狭窄的评价标准的建议。我们最终得到的结果是，跨瓣峰流速、平均梯度和瓣膜面积的复合指标仍然是最稳定和有效的评价瓣膜狭窄的方法。从病理生理学的角度而言，更好的参数，如能量损失系数，能同时考虑到患者可能具有的较高的压力回复波，尤其当主动脉面积较小时。从病理生理学角度，左心室负荷更为重要，而能量损失系数则能较好地反映该指标。另一方面，需要注意的是，变量越复杂，引入计算式的误差就越多，以能量损失系数为例，需要知道流速、瓣膜面积、升主动脉面积等等，这样就有可能产生错误。每一个指标的测量误差是不可避免的，将数据代入公式进行计算时，误差就会被放大。对这些技术而言，谈绝对准确是不现实的。更重要的是我们要深入了解每个测量指标的局限性，如梯度测量的误差来自哪里，瓣膜面积的误差来源在哪里。最终判断狭窄程度时，要综合能获取的所有的信息，包括瓣膜形态、跨瓣流速和压力阶差、计算出的瓣膜面积、左室功能等，当然还要结合患者的症状，才能作出最终判断，决定下一步处置。

International Circulation：Recently， some studies focus on migraine course after transcatheter closure of patent foramen ovale (PFO). Patients who had undergone PFO closure showed a significant reduction in migraine frequency as compared with controls. But some studies are against with the conclusion. We all know that migraine is also a condition where a high psychiatric comorbidity does exist. The efficacy of comprehensive approaches also including counseling for smoking cessation， promotion of lifestyle changes， and stress relief should be objectively measured and tested if not against， at least in addition to PFO closure. What do you think about it? 

《国际循环》：最近，一些研究专注于经导管房间隔缺损封堵术后偏头痛的病情发展。与对照组相比，房间隔缺损封堵术后的患者确实显著减少了偏头痛的发生频率。但另有一些研究结果与此相左。我们知道，偏头痛也是一种与精神障碍相关的疾病，在房间隔缺损封堵术后的患者，治疗途径也包括心理咨询进行戒烟、改善生活方式以及缓解压力等。您是怎样看这个问题的？

Prof. Helmut Baumgartner :The first reports of the accidental finding that， patients with migraine who had PFO or ASD closure for other reasons got rid of their migraine or at least improved was of course exciting and promising. A number of retrospective studies now are showing actually consistently that there’s a high rate of improvement or even complete resolution of migraine after closure of atrial shunts. On the other hand， when we look carefully at these data， these are all retrospective studies with a high likelihood of bias. The only randomized trial we have now is the MIST trial. And the MIST trial has been criticized for some limitations but nevertheless it’s properly performed， a randomized trial， with a control group undergoing a sham procedure to provide blinding. This is very important in migraine because we know from other migraine studies that placebo effects are very high in this disease which needs to be considered. And the MIST trial was absolutely negative; there was a very small number of patients who got rid of the migraine; that was the indeed same in the treatment group and the sham group. And it’s not just for resolution also for the improvement. If you look at the migraine days， and the calculation of migraine burden， then improvement was actually the same in the two groups. Thus， PFO closure can currently not be recommended as a treatment of migraine. There may nevertheless be a subgroup of patients who may benefit from PFO closure but this subgroup still needs to be defined. The only way to do this is with proper research， with really good trials， taking all the messages and all the lessons we have learned from previous studies into account. For right now I don’t think it’s justified to use it in clinical practice because there’s just no evidence. As a matter of fact， the only properly performed trial demonstrated completely negative results. Thus， we would need more supportive data to do this in clinical practice. 

Helmut Baumgartner 教授：第一次报道PFO或卵圆孔未闭（ASD）封堵术后偏头痛的消除或改善是个意外但却令人激动的发现。现在许多回顾性研究也报道了相符的结果，许多患者在先天分流封堵后，其偏头痛有所改善甚至完全缓解。另一方面，如果我们仔细研究这些数据就会发现，它们全部是回顾性研究，而且研究中存在偏倚的可能性很大。现在我们仅有的随机临床试验是MIST研究。虽然MIST研究受到很多批评，指出其存在不少缺陷，但是它始终是遵照随机、对照、双盲原则而严格进行的试验，这对偏头痛研究非常重要，因为我们从其它的偏头痛研究中能够知道，该病的安慰剂效应非常显著，这是必须考虑的。MIST研究的结果完全是阴性的，只有非常少的患者消除了偏头痛，而在治疗组和安慰组之间的偏头痛消失的患者例数相当。此外，从偏头痛的天数以及计算出的患者偏头痛的负荷来看，这2组患者偏头痛的改善情况是相同的。这也就是目前我们