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Abstract: SA-PO501

Pooled, 12-Month Renal Safety and Blood Pressure (BP) Reductions Using the Symplicity Spyral Radiofrequency Renal Denervation Catheter

Session Information

Category: Hypertension and CVD

  • 1602 Hypertension and CVD: Clinical


  • Townsend, Raymond R., University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, United States
  • Mahfoud, Felix, Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes, Homburg, Saarland, Germany
  • Mancia, Giuseppe, Universita degli Studi di Milano-Bicocca, Milano, Italy
  • Kandzari, David Edward, Piedmont Heart Institute, Atlanta, Georgia, United States
  • Whitbourn, Robert, St Vincent's Heart Centre, Melbourne, Victoria, Australia
  • Böhm, Michael, Universitatsklinikum des Saarlandes und Medizinische Fakultat der Universitat des Saarlandes, Homburg, Saarland, Germany

Renal denervation (RDN) targets the sympathetic nervous system to lower blood pressure (BP). Impact on long-term renal function after RDN is less well known. We report the 12-month BP reductions and renal safety after RDN from the largest existing database, using the latest generation, multi-electrode, radiofrequency (RF) Symplicity Spyral™ catheter.


A broad spectrum of patients with hypertension were enrolled in the SPYRAL HTN Global Clinical Program, consisting of 4 major studies; SPYRAL First-In-Man, SPYRAL HTN-OFF MED, -ON MED and Global SYMPLICITY Registry (GSR). GSR is an all-comer registry for patients with uncontrolled hypertension, including chronic kidney disease (CKD), whereas patients enrolled in the SPYRAL HTN-OFF and -ON MED trials required to have OSBP ≥150 and <180 mmHg and ODBP ≥90 mmHg. OFF MED patients were required to have a drug washout period prior to treatment and did not take drugs for the first 3 months. ON MED patients were on a stable 1-3 antihypertensive drug regimen for 6 months.

All were treated with RF RDN using the Spyral catheter. We pooled reductions in office and 24-h ambulatory BP, safety outcomes include changes in the estimated glomerular filtration rate (eGFR) and renal artery stenosis incidence (>70%, confirmed by angiography).


As of March 2023, 1,539 patients received RF RDN using the Spyral catheter. Patients at baseline were 58±12yrs old, 38.2% female, 30.1% had type 2 diabetes, eGFR was 77.9±24.4mL/min/1.73m2, 21.6% had CKD stage 3 or more, OSBP was 164±22mmHg and ASBP was 152±17mmHg. 12 months after RDN, OSBP changed by -15.9 ± 23.2 (n=970; p<0.001) and ASBP changed by -10.0±15.7 (n=660; p<0.001). Significant diastolic BP reductions were also observed. eGFR changed minimally by -2.6mL/min/1.73m2 (n=805; p<0.001). There was no incidence of renal artery stenosis (>70%).


In this large, pooled population of patients receiving RF RDN using the Spyral catheter, there were significant and consistent BP reductions through 12 months. There was no incidence of renal artery stenosis, and eGFR change was consistent with the natural progression of the aging hypertensive population. These data highlight the safety and efficacy of RF RDN as an adjunctive therapy to antihypertensive drugs to treat high BP.


  • Commercial Support – Medtronic Inc