Efficacy and safety of a novel multi-electrode radiofrequency ablation catheter for renal sympathetic denervation in pigs

Objective To investigate the safety and efficacy of a self-developed novel multi-electrode radiofrequency ablation catheter （Spark） for catheter-based renal denervation （RDN）. Methods A total of 14 experimental miniature pigs were randomly divided into four groups （55°＆ 5-watt, 55°＆ 8-watt, 65°＆ 5-watt, and 65° ＆ 8-watt groups）. Spark was used for left and right renal artery radiofrequency ablation. Blood samples collected from renal arteries and veins as well as renal arteriography were performed on all animals before, immediately after, and three months after procedure to evaluate the effects of Spark on the levels of plasma renin, aldosterone, angiotensin I, and angiotensin II as well as the pathological changes of renal arteries. Results One pig died of an anesthetic accident, 13 pigs successfully underwent the bilateral renal artery ablation. Compared with basic measurements, pigs in all the four groups had significantly decreased mean arterial pres- sure after procedure. Histopathological analysis showed that this procedure could result in intimal hyperplasia, significant peripheral sympa- thetic nerve damage in the renal arteries such as inflammatory cell infiltration and fibrosis in perineurium, uneven distribution of nerve fibers, tissue necrosis, severe vacuolization, fTagmented and unclear nucleoli myelin degeneration, sparse axons, and interruption of continuity. In addition, the renal artery radiofrequency ablation could significantly reduce the levels of plasma renin, aldosterone, angiotensin I, and angio- tensin II in pigs. Conclusions The results suggest that this type of multi-electrode catheter-based radiofrequency ablation could effectively remove peripheral renal sympathetic nerves and reduce the activity of systemic renin-angiotensin system in pigs, thus facilitating the control of systemic blood pressure in pigs.

Renal sympathetic nervous system and the effects of denervation on renal arteries

Resistant hypertension is associated with chronic activation of the sympathetic nervous system resulting in various comorbidities. The prevalence of resistant hypertension is often under estimated due to various reasons. Activation of sympathetic nervous system at the renal-as well as systemic-level contributes to the increased level of catecholamines and resulting increase in the blood pressure. This increased activity was demonstrated by increased muscle sympathetic nerve activity and renal and total body noradrenaline spillover. Apart from the hypertension, it is hypothesized to be associated with insulin resistance, congestive heart failure and obstructive sleep apnea. Renal denervation is a novel procedure where the sympathetic afferent and efferent activity is reduced by various techniques and has been used successfully to treat drug-resistant hypertension improvement of various metabolic derangements.Renal denervation has the unique advantage of offering the denervation at the renal level, thus mitigating the systemic side effects. Renal denervation can be done by various techniques including radiofrequency ablation, ultrasound guided ablation and chemical ablation. Various trials evaluated the role of renal denervation in the management of resistant hypertension and have found promising results. More studies are underway to evaluate the role of renal denervation in patients presenting with resistant hypertension in different scenarios. Appropriate patient selection might be the key in determining the effectiveness of the procedure.

Main Renal Artery Plus Branch Ablation in the Treatment of Resistant Hypertension with Renal Denervation

Objective:To study the safety and effi cacy of denervation of renal artery branches in the treatment of resistant hy-pertension.Methods:Sixty patients with resistant hypertension were enrolled.The patients were randomly assigned to the main renal artery plus branch ablation group or the main renal artery ablation group.The clinical data and operation-related parameters,including number of ablation points,temperature,and average energy,were recorded.Ambulatory blood pressure was taken for all patients at the baseline and at 6 months after treatment.Offi ce blood pressure was recorded before treatment and after treatment every 3 months for 2 years.Results:Sixty patients with resistant hypertension were enrolled in this study.There were 30 patients in each group.Angiography was performed after ablation.No renal artery complications,such as stenosis and dissection,occurred in the two groups.There was no signifi cant difference in age,sex,BMI,comorbid disease,and medication between the two groups(P>0.05).The number of ablation points for the main renal artery plus branch ablation group was greater than that for the main renal artery ablation group.The offi ce blood pressure and 24-hour blood pressure were signifi cantly lower 6 months after treatment than before treatment in both groups(P<0.05).Offi ce blood pressure in the main renal artery plus branch ablation group was lower than that in the main renal artery ablation group during the 3-12-month follow-up period,with a statistical difference.However,as the follow-up time increased,the difference disappeared.Conclusion:The results of this study show that main renal artery plus branch ablation is a safe interventional method,but there was no obvious advantage on long-term follow-up compared with only main renal artery ablation.

Renal sympathetic denervation in resistant hypertension

Resistant hypertension remains a major clinical problem despite the available multidrug therapy.Over the next decades,its incidence will likely increase given that it is strongly associated with older age and obesity.Resistant hypertension patients have an increased cardiovascular risk,thus effective antihypertensive treatment will provide substantial health benefits.The crosstalk between sympathetic nervous system and kidneys plays a crucial role in hypertension.It influences several pathophysiological mechanisms such as the central sympathetic tone,the sodium balance and the systemic neurohumoral activation.In fact,studies using several animal models demonstrated that the renal denervation prevented and attenuated hypertension in multiple species.Large reductions in blood pressure were also observed in malignant hypertension patients submitted to sympathectomy surgeries.However,these approaches had an unacceptably high rates of periprocedural complications and disabling adverse events.Recently,an innovative non-pharmacological therapy that modulates sympathetic activation has been successfully developed.Renal sympathetic percutaneous denervation is an endovascular procedure that uses radiofrequency energy to destroy the autonomic renal nerves running inside the adventitia of renal arteries.This method represents a promising new approach to the strategy of inhibiting the sympathetic nervous system.The aim of this review is to examine the background knowledge that resulted in the development of this hypertension treatment and to critically appraise the available clinical evidence.

The application of renal sympathetic denervation in cardiovascular and other diseases

Background The role of renal artery sympathetic nerve ablation,widely known as renal sympathetic denervation(RDN)in the treatment of resistant hypertension(RH)has been clarified,and there is more and more evidence to support its effect in the treatment of heart failure,ventricular hypertrophy and arteriosclerosis.Some studies also reported its role in treatment related to respiratory system(pulmonary hypertension,sleep apnea syndrome),endocrine system(metabolic syndrome,blood lipid metabolism,polycystic ovary syndrome),kidney disease(acute renal injury,renal failure)and other inflammation,remodeling,pain and so on.Though most of them were subgroup analysis and small-sample studies,even case reports,they had shed some light on possible use of RDN in the treatment of multi-system diseases.[S Chin J Cardiol 2024;25(1):57-66].

Advances in non-surgical management of primary liver cancer

Hepatocellular carcinoma(HCC) is the fifth most common cancer and the third most common cause of cancer-related death worldwide. There have been great improvements in the diagnosis and treatment of HCC in recent years, but the problems, including difficult diagnosis at early stage, quick progression, and poor prognosis remain unsolved. Surgical resection is the mainstay of the treatment for HCC. However, 70%-80% of HCC patients are diagnosed at an advanced stage when most are ineligible for potentially curative therapies such as surgical resection and liver transplantation. In recent years, non-surgical management for unrespectable HCC, such as percutaneous ethanol injection, percutaneous microwave coagulation therapy, percutaneous radiofrequency ablation, transcatheter arterial chemoembolization, radiotherapy, chemotherapy, biotherapy, and hormonal therapy have been developed. These therapeutic options, either alone or in combination, have been shown to control tumor growth, prolong survival time, and improve quality of life to some extent. This review covers the current status and progress of non-surgical management for HCC.

Advances in the interventional therapy of hepatocellular carcinoma originating from the caudate lobe

Hepatocellular carcinoma originating from the caudate lobe, also known as segment I hepatocellular carcinoma, is difficult to treat because of its special location, complex vascular supply, and the proximity of important vessels,bile ducts, and organs. This research is conducted to examine the efficacy and safety of interventional therapy for hepatocellular carcinoma in the caudate lobe.Conclusion: Superselective chemoembolization and ablation techniques for the treatment of caudate lobe hepatocellular carcinoma still need to be improved. The combination of multiple interventional methods and the application of multiple imaging techniques can improve the effectiveness and safety of interventional therapy for hepatocellular carcinoma in the caudate lobe. Multidisciplinary treatment is also essential to improve the prognosis of patients with caudate lobe hepatocellular carcinoma.

基于自抗扰控制器的射频消融电极温度控制系统仿真研究

目的将自抗扰控制器(active disturbance rejection controller,ADRC)应用于射频电极并探讨温度控制效果。方法在MATLAB Simulink仿真平台,建立基于ADRC的射频电极温度控制系统,进行阶跃信号实验。加入幅值为2的阶跃信号扰动,以模拟不稳定的人体内环境。最后,将温度滞后时间τ、温度转换时间T和增益系数K值增加20%和50%,与同条件比例-积分-微分(proportion integration differentiation,PID)控制性能对比。结果(1)ADRC调节时间(15.38 s)较PID(18.68 s)短且超调为0。(2)τ与T值变化时,PID超调最大增量分别为3.55%和8.55%,但ADRC超调均为0;K值变化时,ADRC虽出现超调,但同参数下的超调均较PID小。(3)各种参数变化下,两者受干扰后均能在30 s内平稳快速达到设定值。结论ADRC控制技术在射频电极温度控制中显示超调小、稳定速度快、一定的抗干扰性及参数变化适应性,具有良好的调节能力。

高血压犬经导管射频消融去肾交感神经术后血压及神经损伤因子的变化

目的:对高血压犬采用经导管射频消融去肾交感神经术验证其降压疗效,并检测术后神经损伤因子血浆S-100B及神经元特异性烯醇化酶(NSE)含量以探讨其与肾交感神经损伤的关系。方法:12条比格犬随机分为手术组(n=6)和假手术组(n=6)。采用高脂饮食建立高血压模型,手术组实施经导管射频消融去肾交感神经术,假手术组仅行肾动脉造影。观察血压变化,分别在术前和术后第3天、1周、2周、1个月、2个月、3个月监测血压并检测血浆S-100B和NSE的浓度。结果:建模后,手术组及假手术组收缩压(SBP)、舒张压(DBP)、平均动脉压(MBP)较基线均有显著上升(P<0.05)。经导管射频消融去肾交感神经术后,手术组术后1个月及3个月较假手术组SBP,DBP,MBP均有显著下降(P<0.05);术后3个月复查血肌酐正常,复查肾动脉造影未发现肾动脉狭窄。经导管射频消融去肾交感神经术后第3天、1周及2周手术组较假手术组血浆S-100B或NSE的含量升高(P<0.05)。结论:经导管射频消融去肾交感神经术可以显著和持久地降低高血压犬的SBP,DBP及MBP。经导管射频消融去肾交感神经术后S-100B及NSE血浆含量可能作为评估高血压犬肾交感神经损伤的指标。

肾交感神经射频消融术治疗高血压犬的适宜消融温度探讨

目的探讨肾交感神经射频消融术治疗高血压的适宜消融温度。方法成年健康杂种犬20只,雌雄不拘,体质量15～25 kg,建立腹主动脉缩窄型高血压模型后,随机分为治疗组(行双侧肾交感神经射频消融术)和对照组(n=10)。治疗组根据预置消融温度随机分为45℃和50℃组(n=5)。20只犬分别于建模前、建模后1(射频消融术前)、2(术后1个月)、3个月(术后2个月)监测收缩压、舒张压和平均动脉压。建模后3个月治疗组复查肾动脉造影。肾动脉行HE染色观察病理改变。结果建模后1个月,治疗组和对照组血压均显著升高(P<0.01)。射频消融术后1月治疗组收缩压显著降低(P<0.05)。射频消融术后2个月,收缩压、舒张压、平均动脉压均明显低于射频消融术前(P<0.05,P<0.01),且显著低于对照组(P<0.05,P<0.01)。治疗组复查造影未发现肾动脉狭窄及其他异常。肾动脉血管壁病理检查结果显示,50℃组血管壁损伤明显比45℃组严重。结论 45℃可以作为肾交感神经射频消融术治疗高血压的常规消融温度。

经皮肝穿刺射频消融联合肝动脉化疗栓塞治疗原发性小肝细胞癌疗效分析

目的探讨经皮肝穿刺射频消融联合肝动脉化疗栓塞治疗原发性小肝细胞癌的疗效。方法回顾性分析2000年1月至2006年12月我院收治的162例原发性小肝细胞癌的临床资料,其中85例(第一组,共92个病灶)采用经皮肝穿刺射频消融联合肝动脉化疗栓塞治疗,77例(第二组,共85个病灶)采用单纯经皮肝穿刺射频消融治疗。结果第一组肿瘤完全坏死率为96%,1年、3年、5年的生存率及无瘤生存率分别为100%、85.2%、78.7%和87.5%、73.1%、65.7%;而第二组的肿瘤完全坏死率为92%,1年、3年、5年的生存率及无瘤生存率分别为100%、81.3%、72.3%和83.6%、68.7%、57.8%。两组间肿瘤完全坏死率,1年、3年、5年生存率及无瘤生存率的差异皆无统计学意义(P>0.05)。结论经皮肝穿刺射频消融联合肝动脉化疗栓塞治疗原发性小肝细胞癌的疗效与单纯采用经皮肝穿刺射频消融方法疗效相近,对于小肝细胞癌而言,单纯采用经皮肝穿刺射频消融方法是安全有效的。

肾交感神经射频消融术治疗顽固性高血压的进展

目前,抗高血压药物联合治疗顽固性高血压策略取得了良好的临床效果,但仍有部分顽固性高血压的患者无法达到目标血压。近年来,基于动物实验研究和医疗器械技术的进步,一种新的使用射频导管通过微创介入途径有选择性地破坏肾交感神经从而降低血压的方法脱颖而出,为顽固性高血压的治疗提供了一条新思路。文中就肾交感神经射频消融术在顽固性高血压治疗中的研究进展做一综述。

大肝癌患者行TACE序贯射频消融的疗效及复发因素

目的：探讨经导管肝动脉化疗栓塞（TACE）联合序贯射频消融术（RFA）治疗大肝癌患者的疗效及复发因素。方法：选取我院2013年1月-2015年1月肿瘤外科中晚期原发性大肝癌患者110例并分为肝动脉化疗栓塞组（TACE组）与肝动脉化疗栓塞联合序贯经皮射频消融术组（TACE＋RFA组）各55例,TACE组患者行一次或多次单一肝动脉化疗治疗;TACE＋RFA组在肝动脉化疗治疗结束后1~2周再行序贯经皮射频消融术治疗。结果：TACE组与TACE＋RFA组总有效率分别为63.64%（35/55）、94.54%（52/55）。TACE＋RFA组1年生存率为72.7%（40/55）,2年生存率为20.0%（11/55）,而TACE组分别为56.36%（31/55）、7.27%（4/55）。Log-rank检验结果显示肿瘤数量、分期、血清甲胎蛋白水平等为大肝癌患者预后的因素,与患者预后有一定关系。结论：经导管肝动脉化疗栓塞（TACE）联合经皮射频消融术（RFA）治疗原发性中晚期大肝癌可以有效提高患者生存率,延长患者的生存期。肿瘤数量、直径、分期等是影响患者复发的危险因素。

超选择性肾动脉栓塞术联合射频消融治疗肾癌的临床应用

目的探讨超选择性肾动脉栓塞术联合射频消融(RFA)治疗肾癌的疗效。方法分析2009年1月至2011年4月9例肾癌患者超选择性肾动脉栓塞联合RFA。患者均在超选择性肾动脉栓塞术后3～7 d,在CT引导下行RFA。术后1个月行肾脏病灶穿刺活检和CT增强检查评价其疗效。结果 9例患者随访1～6个月,未发现肾脏肿瘤增大,无周围脏器损伤和针道种植。RFA后出现肉眼血尿6例,1周后好转,肾功能治疗前后无明显变化。治疗效果显示部分缓解6例,无变化3例。结论超选择性肾动脉栓塞联合RFA治疗肾癌短期内疗效肯定,并发症少,是肾癌的一种安全有效的治疗手段。

原发性肝癌患者不同方案治疗后近期生活质量的调查

目的比较和分析行手术切除、经肝动脉化疗栓塞(transcatheter hepatic arterial chemoembolization,TACE)及经皮射频消融(percutaneous radiofrequency ablation,PRFA)治疗的原发性肝癌患者术后2个月内的生活质量。方法选择明确诊断为原发性肝癌行手术切除的患者54例、TACE治疗的患者55例、PRFA治疗的患者63例,采用肝癌患者生活质量测定量表2.0版对三组患者术前、术后第5天以及术后第2、4、8周5个时间点进行生活质量各指标的测量。结果 PRFA组患者在躯体功能、社会功能、症状/不良反应等方面,于术后第4周恢复最好,显著优于手术组(P<0.05)。除社会功能外,三组患者在术后第8周时生活质量总分及各维度得分的差异均无统计学意义(P>0.05),且三组患者生活质量总分及各维度得分均高于术前水平。结论 3种治疗方案均可明显提高原发性肝癌患者的术后近期生活质量,PRFA及TACE较手术治疗更使患者受益。对于同时符合手术治疗及微创治疗指征的患者,选择微创治疗可使患者近期获得更优的生活质量。

肾脏交感神经射频消融术治疗顽固性高血压的研究现状与展望

顽固性高血压是指临床上经过使用包括利尿剂在内的、足量且合理的3种或以上抗高血压药物治疗,血压仍未能控制在140/90 mm Hg以下目标值,对于患有糖尿病或肾脏疾病者未能降至130/80 mm Hg以下的高血压。顽固性高血压治疗棘手,预后差,为困扰当今医学界的一大难题。近年来有澳大利亚学者Krum等采用经皮导管肾脏交感神经射频消融术治疗顽固性高血压取得了初步成就,且实验正在向随机、多中心、大样本量标准深化,为顽固性高血压的治疗提供了一条新思路。现将对肾脏交感神经射频消融治疗在顽固性高血压治疗中的研究现状做一综述。

经导管消融选择性去肾交感神经治疗——未来心力衰竭治疗的热点

心力衰竭是各种心脏疾病的终末阶段。近几十年来,心力衰竭的治疗得到了一定的发展,但仍不能明显改善患者生存率,且需长期大量服药,严重影响患者生活质量。大量的研究显示:交感神经系统激活在心力衰竭的发生发展中扮演着重要角色。自上世纪40、50年代,学者们已开始进行去交感神经治疗心力衰竭的尝试,但碍于当时设备和技术的限制,治疗效果不尽人意。可喜的是,澳大利亚的权威学者近几年在美国心脏病学会/美国心脏协会心血管年会上介绍了一种安全、有效的新型去肾交感神经的方法,即经导管消融选择性去肾交感神经。该研究证实此方法可以明显降低全身交感活性。那么经导管消融去肾交感神经治疗能否成为未来心力衰竭治疗的热点呢?现将对去交感神经治疗心力衰竭的现状和进展做一综述。

肾动脉交感神经消融术治疗顽固性高血压研究现状

肾动脉交感神经消融术治疗顽固性高血压已应用于临床,国内外学者对该方法的操作步骤、疗效、并发症已进行了一系列研究。运用肾动脉交感神经消融术治疗顽固性高血压,创伤小,成功率较高,有一定疗效。但是在治愈率、术后并发症、温度场的预测等方面尚存在不足。因此,要在术前制定合理的手术规划系统,以保证交感神经的彻底消融,避免并发症的产生。

内镜联合肝动脉栓塞化疗、射频消融治疗肝细胞癌合并胆管癌栓

目的探讨内镜联合肝动脉栓塞化疗(transcatheter arterial chemoembolization,TACE)、射频消融(percutaneous radiofrequency ablation,PRAF)治疗肝细胞癌(hepatocellular carcinoma,HCC)合并胆管癌栓的治疗效果。方法回顾总结1999年1月-2005年12月收治的65例肝细胞癌合并胆管癌栓的诊疗情况。结果65例中,均行内镜胆道引流术或EST及取栓,联合TACE,PRAF治疗。本组无手术死亡。癌栓清除率为95.4%(62/65),肿瘤坏死率为96.9%(63/65),1年生存率为60.0%(39/65),3年生存率为38.5%(25/65)。结论内镜联合TACE及PRAF治疗肝细胞癌合并胆管癌栓不失为一种行之有效的微创治疗方法,疗效优于单纯的内镜、TACE及PRAF治疗。

常规温控型心脏消融导管在肾动脉交感神经丛消融术中的安全性和有效性

目的通过离体和在体动物实验观察常用的温控型非灌注心脏消融导管在肾动脉交感神经丛消融术中的效果及其安全性。方法①电生理消融池中,在新鲜猪肾动脉条上采用不同的功率和消融时间进行消融,探索常规温控型非灌注心脏消融导管合适的消融功率。②将10只小型猪编号,随机分入3组:假手术组(3只)小香猪在插入消融导管后不放电,结束操作后处死;即刻处死组(4只)小香猪行单侧肾动脉消融后即行肾动脉造影并即刻处死;长期随访组(3只)同即刻处死组方法消融后3个月行肾动脉造影后处死。分别取肾动脉行苏木精-伊红(H-E)染色和改良交感神经嗜银染色,置于光学显微镜下观察,了解肾动脉和交感神经损伤情况。结果消融30s时,消融功率为8、10、12 W下肾动脉损伤面积占血管横切面周长的百分率分别为(27.3±1.5)%、(28.8±3.3)%和(28.3±2.6)%;消融60s时,分别为(26.7±2.4)%、(30.0±5.1)%和(29.4±2.1)%;同功率不同时间点间和同时间点不同功率间的差异均无统计学意义(P值均<0.05)。各消融功率下均可见肾动脉全层透壁性损伤,为避免不必要的周围组织(如肾脏的肾盂和近端输尿管)损伤,在体实验拟采用最小功率8W、30s作为消融参数。长期随访组行手术消融的18个位点在术后3个月仅有3个位点的狭窄程度<5%,平均狭窄程度为(3.5±2.1)%,显著低于即刻处死组的(40.8±17.3)%(P<0.05)。假手术组、即刻处死组、长期随访组的损伤面积占血管横切面周长的百分率分别为0、(26.8±4.2)%、(39.5±8.3)%,损伤深度分别为0、(1 225.1±101.7)、(1 718.6±112.3)μm,即刻处死组与长期随访组间的差异均有统计学意义(P值均<0.05)。长期随访组神经束损伤特点、程度与即刻处死组相似。结论常规温控型非灌注心脏消融导管在肾动脉交感神经丛消融术中可造成有效的肾动脉交感神经丛损伤,同时其血管损伤表面积大,增生性改变明显,血管安全性值得关注。