title: Efficacy and safety of a novel multi-electrode radiofrequency ablation catheter for renal sympathetic denervation in pigs.
abstract: 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 pressure after procedure. Histopathological analysis showed that this procedure could result in intimal hyperplasia, significant peripheral sympathetic nerve damage in the renal arteries such as inflammatory cell infiltration and fibrosis in perineurium, uneven distribution of nerve fibers, tissue necrosis, severe vacuolization, fragmented 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 angiotensin 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.
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Gan
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Xin-Kai
authors.initials: XK
authors.lastname: Qu
authors.affiliation: Department of Cardiology, the Second Clinic Medical College, Yangzhou University, Yangzhou, China.
authors.forename: Kai-Zheng
authors.initials: KZ
authors.lastname: Gong
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Shao-Feng
authors.initials: SF
authors.lastname: Guan
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Wen-Zheng
authors.initials: WZ
authors.lastname: Han
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Jin-Jie
authors.initials: JJ
authors.lastname: Dai
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Ruo-Gu
authors.initials: RG
authors.lastname: Li
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Min
authors.initials: M
authors.lastname: Zhang
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Hua
authors.initials: H
authors.lastname: Liu
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Ying-Jia
authors.initials: YJ
authors.lastname: Xu
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: You-Jun
authors.initials: YJ
authors.lastname: Zhang
authors.affiliation: Department of Cardiology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
authors.forename: Wei-Yi
authors.initials: WY
authors.lastname: Fang
keywords: Multi-electrode catheter; Radiofrequency ablation; Renal artery