德克萨斯大学健康科学中心心脏科主任 Steven R. Bailey

　　International Circulation：We’re going to be asking about the percutaneous treatment of hypertension. Could you give us a brief introduction to the current state of the percutaneous treatment of hypertension?
　　《国际循环》：下面我们将向您咨询关于经皮高血压治疗的问题。您能为我们简单介绍一下经皮高血压治疗的现状吗？
　　PROF BAILEY:Absolutely. So， for two decades we have tried treating arterial blockages in order to alleviate high blood pressure， hypertension. It’s been very clear that in some patients that’s very effective. We have not been very good at identifying in which patients it’s going to be beneficial yet. There are some suggestions that having a significant blockage， defined as a hyperemic response， can identify that group. What has become more clear over the last eight to 10 years is that hypertension is probably less dependent upon the blood flow through the renal arteries， and more dependent upon the sympathetic and parasympathetic nervous system. And that’s brand new news.
　　PROF BAILEY:当然可以。20年来，我们一直在努力通过治疗动脉阻塞来降低血压，而且很明确的是，对有些病人效果十分显著。但是我们在识别哪些患者会从治疗获益这方面做的还不够好。有的意见认为，有显著阻塞（定义为有充血反应）的患者更容易从治疗中获益。近8-10年来，高血压和肾动脉血流的相关性可能较小，而与交感神经以及副交感神经系统的关系更大这一点越来越明确。这是个重要的新信息。
　　International Circulation：What are the new ways of treating hypertension?
　　《国际循环》：治疗高血压的新方法包括哪些？
　　PROF BAILEY:What we’ve discovered is that， as physicians have known for years， if you press on the carotid arteries you， through the brain， illicit some very important responses. One is that you block or decrease the sympathetic nerve output and the other is that parasympathetic nerves are increased. Through that kind of response you can actually decrease heart rate — which is why most doctors rub on the carotid artery —and you also result in direct effects on the kidneys， decreasing the release of chemicals that raise blood pressure and increasing the release of sodium. Chronically stimulating the vagus nerve can do that.There are now different systems that stimulate the vagus nerve directly – baroreflex stimulation. People are also looking at spinal cord stimulation as a mechanism. The third primary process is through the sympathetic nerves that run to the kidneys. These nerves run from the spinal column， from T10 to L1， and they actually track along the outside of the renal arteries. Because of that they’re available to different treatments. One of the most robust of those has been the use of a radiofrequency catheter and the techniques that we commonly use for renal artery treatments with stents: So， through a catheter， from the leg， or from the arm， you can get inside of the renal artery， deliver radiofrequency， a kind of energy that actually will get outside of the artery to the adventitia， or the lining part of the artery， which is where these nerves are. It takes about 30 minutes and you can treat four to six different sites.By treating these nerves，you interfere with these nerves and it turns out that it results in an increase in the amount of sodium that’s released and a decrease in the chemicals that cause hypertension. There’s some other effects as well that weren’t anticipated. We didn’t realize that sleep apnea is part of the same process， that there is evidence that chronic narrowing， or vasoconstriction， and the development of atherosclerosis is sympathetically tone mediated. There are some suggestions that even things like diabetes – insulin release – are associated as well.
　　PROF BAILEY:正如医生们早已了解的那样，我们发现，如果你压迫颈动脉窦，会通过大脑引起非常重要的反应，即减少了交感神经的信号输出而增加了副交感神经的信号输出。通过这种反应可以降低心率——这就是很多医生通过按摩颈动脉窦治疗心律失常的原因。按摩颈动脉窦还可以引起肾脏的直接反应，即减少升压化学物质的释放，增加钠的排泄。长期刺激迷走神经也可以达到这个效果。此外，还有可以直接刺激迷走神经的系统——压力反射刺激。脊髓刺激也被看做一种神经反应机制。第三个主要的机制是通过支配肾脏的交感神经。这些神经位于脊柱的胸10到腰1节段，并且沿肾动脉外周分布。因此，它们可以用于不同的治疗方法。最可靠的治疗方法之一是采用通常用于肾动脉支架植入的方法进行经皮介入治疗，使用射频导管进行消融：治疗过程是使用导管经下肢或上肢血管，进入肾动脉内部交感神经分布的位置，从肾动脉之外而内到动脉外膜或内部释放射频能量。用大约30分钟的时间可以在四到六个不同的部位进行治疗。通过对肾交感神经的治疗和干预，增加了钠离子排泄量，减少了导致高血压的化学物质的释放。治疗也会产生另外一些我们意想不到的效应，我们之前并没有认识到睡眠呼吸暂停也与交感神经相关，并且目前有证据证实血管慢性狭窄，血管收缩，以及动脉粥样硬化也可由交感神经介导。有的研究发现提示我们即使是糖尿病，胰岛素的释放，也与交感神经相关。

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