title: The effect of percutaneous renal denervation on muscle sympathetic nerve activity in hypertensive patients.
abstract: OBJECTIVE
  The rationale of percutaneous renal denervation (RDN) is based on extensive studies suggesting that renal nerves contribute to hypertension and that they comprise a sensible treatment target. Muscle sympathetic nerve activity (MSNA) is considered to be one of the few reliable methods to quantify central sympathetic activity. The aim of this current study is to determine the effect of RDN on MSNA in a standardized fashion.
  
  
  METHODS
  MSNA was determined in 13 patients before and 6months after RDN. Anti-hypertensive medication was stopped before MSNA. If cessation of medication was considered unsafe, a patient was instructed to use the exact same medication on both occasions.
  
  
  RESULTS
  Ten sets of MSNA recordings were of good quality for analysis. Mean age was 57 ± 3 years and mean eGFR was 85 ± 18 mL/min/1.73 m(2). MSNA was determined twice during a medication free interval in 5 patients; 1 patient used the exact same medication twice, and 4 patients used different drugs. Mean BP changed from 206 ± 7 over 116 ± 4 mmHg, to 186 ± 6 over 106 ± 3 mmHg, 6 months after RDN (p=0.06 for systolic BP, p=0.04 for diastolic BP). Mean resting heart rate did not change (p=0.44). MSNA did not change after RDN: 37 ± 4 bursts/min and 43 ± 4 bursts/min (p=0.11) at baseline and after RDN, respectively. In the 6 patients with standardized medication use during the MSNA sessions, results were comparable.
  
  
  CONCLUSIONS
  Treatment with RDN did not result in a change in MSNA. Changes in BP did not correlate with changes in MSNA.
authors.affiliation: Department of Nephrology, University Medical Center Utrecht, The Netherlands. Electronic address: e.e.vink-2@umcutrecht.nl.
authors.forename: E E
authors.initials: EE
authors.lastname: Vink
authors.affiliation: Department of Cardiology, University Medical Center Utrecht, The Netherlands. Electronic address: w.l.verloop@umcutrecht.nl.
authors.forename: W L
authors.initials: WL
authors.lastname: Verloop
authors.affiliation: Department of Nephrology, University Medical Center Utrecht, The Netherlands. Electronic address: l.siddiqi-2@umcutrecht.nl.
authors.forename: L
authors.initials: L
authors.lastname: Siddiqi
authors.affiliation: Department of Medical Technology and Clinical Physics, University Medical Center Utrecht, The Netherlands. Electronic address: l.j.vanschelven@umcutrecht.nl.
authors.forename: L J
authors.initials: LJ
authors.lastname: van Schelven
authors.affiliation: Department of Nephrology, University Medical Center Utrecht, The Netherlands. Electronic address: p.l.oey@umcutrecht.nl.
authors.forename: P
authors.initials: P
authors.lastname: Liam Oey
authors.affiliation: Department of Nephrology, University Medical Center Utrecht, The Netherlands. Electronic address: P.J.Blankestijn@umcutrecht.nl.
authors.forename: P J
authors.initials: PJ
authors.lastname: Blankestijn
mesh_terms: D000328:Adult; D000368:Aged; D017115:Catheter Ablation / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000601:surgery*; D007668:Kidney / Q000098:blood supply / Q000294:innervation* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D012077:Renal Artery / Q000294:innervation / Q000601:surgery; D013562:Sympathectomy / Q000379:methods*; D017779:Sympathetic Fibers, Postganglionic / Q000601:surgery*; D016896:Treatment Outcome
keywords: Blood pressure; Muscle sympathetic nerve activity; Renal denervation; Resistant hypertension; Sympathetic activity