无线电波用于肾脏去神经支配可有效控制血压

　难治性高血压是心脏病和中风的主要风险因素，根据一项刊登在美国心脏协会期刊的新研究表明，在不采取药物治疗的情况下，对肾脏周围神经持续发射短脉冲6个月至一年能有效控制血压，这项研究对难治性高血压的治疗具有深远的公共健康学影响。

　　血压高于140/90mm Hg被称为高血压，美国有78万成年患者受高血压影响。在美国高血压成年患者中，约9%患有难治性高血压，这表示他们需要服用4种以上药物来控制血压，或者说，当他们服用3种不同的降压药后血压仍然高于140/90mm Hg.研究将很快确定这种方法是否能够治愈轻度高血压，使患者在永久停药的情况下保持正常血压。一旦达到血压正常值，心脏病和中风的风险预计将减少40%以上。基于导管的肾脏去神经支配疗法是一种微创的治疗方法。医生将导管经股动脉插入腹股沟，发射无线电波烧毁肾动脉周围的神经组织。

　　该实验结果来自于一项持续多中心国际研究Symplicity HTN-2，以评估肾脏去神经支配法对高血压的疗效。这项研究基于2010年的一个发现，该发现显示对肾脏动脉周围神经发射无线电波6个月后，耐药高血压患者血压降低。

　　对照组参与者之前未接受此项治疗，基于接受治疗的患者出现积极反应，对照组患者接受肾脏去神经支配法。研究者选取35例对照组患者接受治疗并与47例之前接受过治疗的患者进行对比。参与者血压达到160mmHg或更高，服用3种以上抗高血压药，一些伴有糖尿病等其他疾病。研究者对参与者肾动脉进形成像来显示血压变化过程。

　　研究者发现超过83%第一批接受肾脏去神经支配疗法的患者6个月内收缩压降低至少10mmHg，约79%12个月内保持这种情况。后来接受治疗的对照组效果类似，约63%降低10mmHg并维持至少6个月。参与治疗的患者肾脏未由于功能受损遭到破坏，并未产生长期的副作用。

　　Radio Waves To Kidneys Lower Persistent High Blood Pressure

　　Main Category: Hypertension

　　Also Included In: Urology / Nephrology

　　Article Date: 24 Dec 2012 - 0:00 PST

　　Directing short bursts of radio waves at nerves surrounding the kidneys lowered blood pressure for at least six months and up to one year among patients with hypertension that persists regardless of taking multiple medications to control it, according to a new study published in the American Heart Association journal, Circulation.

　　The findings could have significant public health implications in the treatment of resistant hypertension, a major risk factor for heart attack and stroke, said Murray Esler, M.B.B.S., Ph.D., Professor and Senior Director of the Baker IDI Heart and Diabetes Institute in Melbourne, Australia.

　　Hypertension, which is blood pressure higher than 140/90 mm Hg, affects more than 78 million adults in the United States. Among adults with high blood pressure in the United States, about 9 percent have resistant hypertension - meaning they take four or more medications to control their blood pressure, or blood pressure is still higher than 140/90 mm Hg while taking three different blood pressure medicines.

　　"Studies will soon determine whether this procedure can cure mild hypertension, producing permanent drug-free normalization of blood pressure," Esler said. "Based on the blood pressure declines achieved, reduction in heart attack and stroke rates of more than 40 percent is anticipated."

　　Catheter-based renal denervation is a minimally-invasive procedure in which doctors use a catheter, inserted through the femoral artery in the groin, to send radio waves that burn away nerve tissue around the kidney arteries. The goal is to destroy the nerves around the kidneys, which help control and filter salt through the body and may be overactive among patients with hypertension.

　　The results come from Symplicity HTN-2, an ongoing, multicenter, international study evaluating renal denervation for the treatment of hypertension. These findings build on results released in 2010, which showed that six months of treating the nerves around the kidney arteries with radio waves lowered drug-resistant high blood pressure.

　　Participants who began in the control group of the initial study, and did not have the procedure, were invited to "cross over" and receive renal denervation based on the positive outcomes of the patients who had already received the treatment.

　　A total of 35 control patients from the earlier study chose to receive renal denervation and were compared with 47 patients who had been among the first wave of patients to have it. Study participants had drug-resistant hypertension at 160 mm Hg or higher, had taken three or more anti-hypertension drugs, and some had other conditions including diabetes. All had undergone renal artery imaging to ensure the arteries around the kidney could withstand the procedure.

　　In the new study, Esler and his team found that more than 83 percent of the initial renal denervation treatment group experienced a drop in systolic blood pressure of at least 10 mm Hg at six months and nearly 79 percent of the group maintained such reductions at 12 months. The crossover group showed similar results with almost 63 percent reducing systolic blood pressure of 10 mm Hg or more six months after starting the treatment.

　　"Participants' kidneys were not damaged or functionally impaired," Esler said. "We also found no ill effects on long-term health from the procedure."