title: Randomised, blinded and controlled comparative study of chemical and radiofrequency-based renal denervation in a porcine model.
abstract: OBJECTIVE
  The blood pressure-lowering effect of percutaneous renal denervation (RDN) is controversial. The success of RDN may be device-dependent. We sought to compare the efficacy of RDN by chemical neurolysis using alcohol (Peregrine System Infusion Catheter; Ablative Solutions, Inc., Menlo Park, CA, USA) to RDN by radiofrequency (RF) ablation with the single-electrode RF catheter (Symplicity Flex; Medtronic, Minneapolis, MN, USA) in a porcine model.
  
  
  RESULTS
  This was a prospective, randomised, blinded study. Pigs were assigned to undergo bilateral RF ablation or chemical neurolysis. Primary endpoints were ablation depth and renal tissue norepinephrine (NE) concentrations at three-month follow-up. Twelve pigs underwent RF ablation (n=4) or chemical neurolysis by infusion of 0.3 mL (n=4) or 0.6 mL (n=4) alcohol. Ninety days after RF ablation and chemical neurolysis with 0.3 mL and 0.6 mL of alcohol, mean maximal tissue injury depth was 3.9±1.2 mm, 6.6±1.7 mm and 8.2±2.2 mm, respectively (p<0.001 for either dose of alcohol vs. RF ablation). Compared with historical controls, median renal tissue NE concentration reductions were 66%, 78% and 83% after RF ablation and chemical neurolysis using 0.3 mL and 0.6 mL alcohol, respectively (p=0.107 for chemical neurolysis vs. RF ablation). Mean total ablation area was significantly greater in both (0.3 mL and 0.6 mL) alcohol groups (p=0.0001 for both) than the RF ablation group (30.8±13.7 mm2, 41.6±12.4 mm2 and 11.0±7.5 mm2, respectively).
  
  
  CONCLUSIONS
  RDN is more effective using chemical neurolysis than single-electrode RF ablation. Our findings suggest that the efficacy of RDN may be device-dependent.
authors.affiliation: CardioVascular Center Frankfurt, Frankfurt, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Bertog
authors.forename: Tim A
authors.initials: TA
authors.lastname: Fischel
authors.forename: Félix
authors.initials: F
authors.lastname: Vega
authors.forename: Vartan
authors.initials: V
authors.lastname: Ghazarossian
authors.forename: Atul
authors.initials: A
authors.lastname: Pathak
authors.forename: Laura
authors.initials: L
authors.lastname: Vaskelyte
authors.forename: Darrin
authors.initials: D
authors.lastname: Kent
authors.forename: Horst
authors.initials: H
authors.lastname: Sievert
authors.forename: Elena
authors.initials: E
authors.lastname: Ladich
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Yahagi
authors.forename: Renu
authors.initials: R
authors.lastname: Virmani
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000627:therapeutic use; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D017115:Catheter Ablation / Q000295:instrumentation* / Q000379:methods; D006973:Hypertension / Q000601:surgery*; D007668:Kidney / Q000601:surgery*; D023421:Models, Animal; D009638:Norepinephrine / Q000627:therapeutic use; D011446:Prospective Studies; D012077:Renal Artery / Q000601:surgery*; D013552:Swine; D013562:Sympathectomy / Q000295:instrumentation* / Q000379:methods
chemical_list: D000959:Antihypertensive Agents; D009638:Norepinephrine