title: Mid-Term Vascular Safety of Renal Denervation Assessed by Follow-up MR Imaging.
abstract: OBJECTIVE
  Renal denervation (RDN) emerged as a treatment option for reducing blood pressure (BP) in patients with treatment-resistant hypertension (TRH). However, concerns have been raised regarding the incidence of late renal artery stenosis or thromboembolism after RDN. The goal of the current study was, therefore, to conduct a prospective clinical trial on the mid-term vascular integrity of the renal arteries and the perfusion of the renal parenchyma assessed by magnetic resonance imaging (MRI) in the follow-up after catheter-based RDN.
  
  
  METHODS
  In our single-centre investigator initiated study, 51 patients with true TRH underwent catheter-based RDN using the Symplicity Flex(TM) catheter (Medtronic Inc., Palo Alto, CA). Follow-up MRI was performed at a median of 11 months (interquartile range 6-18 months) after RDN on a 1.5T MR unit. High-resolution MR angiography (MRA) and MRI results were compared to the baseline digital angiography of renal arteries obtained at time of RDN. In case of uncertainties (N = 2) catheter angiography was repeated.
  
  
  RESULTS
  Both office and 24-h ambulatory BP were significantly reduced 6 and 12 months after RDN. Renal function remained unchanged 6 and 12 months after RDN. In all patients, MRA excluded new or progression of pre-existing low grade renal artery stenosis as well as focal aneurysms at the sites of radiofrequency ablation. In none of the patients new segmental perfusion deficits in either kidney were detected on MRI.
  
  
  CONCLUSIONS
  No vascular or parenchymal complications after radiofrequency-based RDN were detected in 51 patients followed up by MRI.
authors.affiliation: Department of Radiology, Friedrich-Alexander University Erlangen-Nuremberg, Maximiliansplatz 1, 91054, Erlangen, Germany. axel.schmid@uk-erlangen.de.
authors.forename: Axel
authors.initials: A
authors.lastname: Schmid
authors.affiliation: Department of Radiology, Friedrich-Alexander University Erlangen-Nuremberg, Maximiliansplatz 1, 91054, Erlangen, Germany.
authors.forename: Raphael
authors.initials: R
authors.lastname: Schmieder
authors.affiliation: Department of Radiology, Friedrich-Alexander University Erlangen-Nuremberg, Maximiliansplatz 1, 91054, Erlangen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Lell
authors.affiliation: Department of Radiology, Friedrich-Alexander University Erlangen-Nuremberg, Maximiliansplatz 1, 91054, Erlangen, Germany.
authors.forename: Rolf
authors.initials: R
authors.lastname: Janka
authors.affiliation: Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Roland
authors.initials: R
authors.lastname: Veelken
authors.affiliation: Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Roland E
authors.initials: RE
authors.lastname: Schmieder
authors.affiliation: Department of Radiology, Friedrich-Alexander University Erlangen-Nuremberg, Maximiliansplatz 1, 91054, Erlangen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Uder
authors.affiliation: Department of Nephrology and Hypertension, Friedrich-Alexander University Erlangen-Nuremberg, Erlangen, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Ott
mesh_terms: D000368:Aged; D017115:Catheter Ablation; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000188:drug therapy / Q000601:surgery*; D007668:Kidney / Q000098:blood supply* / Q000000981:diagnostic imaging / Q000294:innervation*; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012077:Renal Artery / Q000294:innervation / Q000601:surgery*; D013562:Sympathectomy / Q000379:methods*
keywords: Follow-up; Magnetic resonance angiography; Renal artery stenosis; Renal denervation; Renal function; Safety