采访撷要

　　经皮肾脏交感神经射频消融术：需要注意什么？

　　在经皮肾脏交感神经射频消融术前，通常对患者行肾脏超声检查，以观察是否存在肾动脉狭窄，随后行肾动脉血管造影进一步确诊，在此过程中，我们确实发现一些患者存在肾动脉狭窄。目前，合并肾动脉狭窄患者治疗方式存在争议。我曾接诊一位患者，其一侧肾动脉存在约50%的狭窄，未进行处理；另一侧肾动脉则为高度狭窄，我们先行动脉扩张，随后实施了肾脏交感神经射频消融术，并在扩张动脉部位置入一枚支架。避免在动脉粥样硬化或钙化的区域实施肾脏交感神经射频消融术，这点很重要，因为在此区域操作可能导致不稳定斑块的产生。
　　一般操作时都会有非常轻微的动脉痉挛。有时观察到严重血管痉挛。但迄今为止，所观察到的血管痉挛都能自行缓解。操作时碰到的主要问题是肾动脉狭窄，可能5000例患者中有一例患者存在肾动脉狭窄，此时我们采取螺旋肾脏交感神经射频消融术的方法，避免消融部位相互连接。通常保持消融部位之间相隔5 mm，并改变消融的部位。
　　按照我们的经验，术后通常至少需4周血压开始下降，6个月内能观察到血压进行性下降。ACC大会上公布的一些数据显示，术后血压下降时间超过6个月，但我认为，如果患者术后6个月内血压未下降，则属于手术无效者。但这部分患者数量较少，目前并未对此展开研究。另外，术后随访非常重要，应观察患者是否发生低血压。如果患者收缩压降至130 mm Hg或120 mm Hg以下，则应减少降压药物用量。但是，术前并不主张减少药物用量，患者通常维持一定量的药物治疗。

　　International Circulation: Can you tell us about the assessment of the anatomy with regard to renal denervation? What things are you looking for?
　　Dr Weil: What we usually do is perform ultrasound on the kidneys to check for renal stenosis. I know there are some people doing MRI studies or CT but I think this is very expensive on one hand and on the other hand if you do CT scans you have the radiation. We check by ultrasound and then we go into the renal artery and look again with the angiogram. That is the first thing we do and we have seen some stenoses.
　　International Circulation: What happens if there are stenoses present?
　　Dr Weil: If we see stenoses， it is a matter of debate. I had a patient last week who had a double-sided stenosis. One stenosis was around 50% occluded so we don’t touch those and the other one was a high degree so I dilated it， went in with a catheter and did my ablation and then put a stent into the dilated area. It is important not to ablate in the atherosclerotic area or where there is some calcification because you might produce an unstable plaque. So we just avoid these areas. Anything that looks diseased you don’t touch.
　　International Circulation: What amount of spasming would you expect to see?
　　Dr Weil: Very small vasospasms you almost always see. They are very faint but you can see notches in the vessel. We have one in a hundred patients have a severe spasm which resolves over time. That is also the experience from other groups that sometimes severe spasms do occur. So far they resolve on their own. Maybe if you have treated 5000 patients， then maybe you will see a stenosis which would be the main concern which is why we do a spiral ablation pattern going back so that ablated areas are not adjacent to each other. We always maintain the 5mm gap and change the position.
　　International Circulation: Can you outline why it is important to discuss with the patient what to expect after the procedure?
　　Dr Weil: Some people would believe that the hypertension is gone by the next morning. Certainly it should be reduced by the next morning because they have been in bed all night and the day before after the procedure， but that is not the effect of the procedure. Usually it takes， in our hands， at least four weeks before the blood pressure goes down and you can see a progressive drop over six months. Actually there was some data at ACC presented by Paul Sobotka showing that you have blood pressure reduction over more than six months but usually it is my opinion that if you have no reduction by six months you have a non-responder. However， the numbers are still very low and it has not been evaluated formally addressing this question. Usually though it is one month and then the pressure declines.
　　《国际循环》：请您介绍一下肾交感神经射频消融术当中的解剖学评价？您观察的是哪些方面？
　　Weil博士：我们通常的做法是进行肾脏超声检查，观察有无肾动脉狭窄。我知道有一些人在开展MRI或CT研究，不过我认为一方面MRI和CT检查非常昂贵，另一方面CT检查会带来辐射。我们则采用超声检查来观察肾动脉，之后还会做肾动脉血管造影。这是我们在肾交感神经射频消融术前首先要做的事情，确实发现一些患者有肾动脉狭窄。
　　《国际循环》：如果有肾动脉狭窄怎么办？
　　Weil博士：发现肾动脉狭窄后的做法还有争议。我上周接诊了一个有双侧肾动脉狭窄的患者。一侧肾动脉大约有50%的闭塞，我们没有进行操作；另一侧肾动脉为高度狭窄，我们进行了动脉扩张，插入导管后实施了肾交感神经射频消融术，随后在扩张动脉部位放入一个支架。重要的是不要在有动脉粥样硬化或钙化的区域实施肾交感神经射频消融术，因为操作可能会导致不稳定斑块的产生。因此我们避免了上述区域。任何看起来像病变的组织都不要碰。
　　《国际循环》：操作时动脉痉挛的程度如何？
　　Weil博士：一般都会有非常轻微的动脉痉挛。痉挛是非常微弱的，但是你会观察到血管里有痕迹。我们发现，每一百个患者里有一例患者发生了严重的血管痉挛，不过随着时间推移而缓解。其他研究小组也有这样的经验，有时候会观察到严重的血管痉挛。迄今为止，所观察到的血管痉挛都能够自行缓解。比如说你治疗了5000例患者，可能会看到有一例患者的肾动脉狭窄是主要问题，此时我们采取的是螺旋肾交感神经射频消融术的方法，也就是折回来进行消除，这样消除的部位彼此就不是互相连接的。我们会始终保持消除部位之间相隔5 mm，改变消除的部位。
　　《国际循环》：请您简要介绍一下为什么与患者探讨肾交感神经射频消融术后的结果是重要的？
　　Weil博士：一些患者认为术后第二天高血压就治好了。当然，第二天早上血压会有所降低，因为患者术后睡了一整夜，术前一天也睡了一整夜，但是此种血压降低并不是手术本身所带来的。按照我们的经验，通常至少需要4周血压才能下降，在6个月内会观察到血压的进行性下降。实际上，在ACC由Paul Sobotka公布的一些数据显示，术后血压降下来的时间超过6个月，不过我通常认为，如果患者在6个月之内血压没降下来的话，该患者就属于无反应者。但是，无反应者所占的比例相当低，对这个问题还没有开展正式的研究。不过，通常是在4周时开始血压下降，之后持续降低。