title: Bilateral or unilateral stimulation for baroreflex activation therapy.
abstract: Previous trials have shown that in patients with resistant hypertension device-based baroreflex activation therapy (BAT) can substantially reduce blood pressure. However, the fact that electrodes had to be implanted bilaterally may be a drawback for further development of the technique. In this study, we explored whether unilateral stimulation would produce comparable results as bilateral stimulation. In the Pivotal trial, treatment-resistant hypertensive patients were randomized to receive either immediate BAT or deferred BAT, that is, 6 months after implantation. We adjusted stimulation parameters individually so as to provide optimal baroreflex activation. Unilateral stimulation was applied unless bilateral stimulation resulted in a greater blood pressure reduction. When we pooled the 6-month data for the group with immediate BAT and the 12-month data for the group with deferred BAT, a total of 215 patients had been stimulated on one side only (127 at the right side and 88 at the left side), whereas 80 patients had been stimulated bilaterally. Although blood pressure and heart rate did not differ between the 2 groups at baseline, all these variables were significantly lower in the unilateral than in the bilateral group after the 6-month period. When we compared the effect of right-sided stimulation with those of either left-sided or bilateral stimulation, we found right-sided stimulation to be the most effective. We conclude that unilateral and in particular right-sided BAT has a more profound effect on blood pressure than bilateral or left-sided BAT.
  
  
  BACKGROUND
  http://www.clinicaltrials.gov. Unique identifier: NCT00442286.
authors.affiliation: From the Department of Medicine, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (P.W.d.L., T.A., A.A.K.); CVRx Inc, Minneapolis, MN (E.L.); Division of Nephrology, Virginia Commonwealth University Health System, Richmond (D.S.); Department of Internal Medicine, Division of Cardiology, University of Rochester Medical Center, NY (J.B.); and Department of Nephrology and Hypertension, Medizinische Hochschule Hannover, Hannover, Germany (H.H.). p.deleeuw@maastrichtuniversity.nl.
authors.forename: Peter W
authors.initials: PW
authors.lastname: de Leeuw
authors.affiliation: From the Department of Medicine, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (P.W.d.L., T.A., A.A.K.); CVRx Inc, Minneapolis, MN (E.L.); Division of Nephrology, Virginia Commonwealth University Health System, Richmond (D.S.); Department of Internal Medicine, Division of Cardiology, University of Rochester Medical Center, NY (J.B.); and Department of Nephrology and Hypertension, Medizinische Hochschule Hannover, Hannover, Germany (H.H.).
authors.forename: Teba
authors.initials: T
authors.lastname: Alnima
authors.affiliation: From the Department of Medicine, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (P.W.d.L., T.A., A.A.K.); CVRx Inc, Minneapolis, MN (E.L.); Division of Nephrology, Virginia Commonwealth University Health System, Richmond (D.S.); Department of Internal Medicine, Division of Cardiology, University of Rochester Medical Center, NY (J.B.); and Department of Nephrology and Hypertension, Medizinische Hochschule Hannover, Hannover, Germany (H.H.).
authors.forename: Eric
authors.initials: E
authors.lastname: Lovett
authors.affiliation: From the Department of Medicine, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (P.W.d.L., T.A., A.A.K.); CVRx Inc, Minneapolis, MN (E.L.); Division of Nephrology, Virginia Commonwealth University Health System, Richmond (D.S.); Department of Internal Medicine, Division of Cardiology, University of Rochester Medical Center, NY (J.B.); and Department of Nephrology and Hypertension, Medizinische Hochschule Hannover, Hannover, Germany (H.H.).
authors.forename: Domenic
authors.initials: D
authors.lastname: Sica
authors.affiliation: From the Department of Medicine, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (P.W.d.L., T.A., A.A.K.); CVRx Inc, Minneapolis, MN (E.L.); Division of Nephrology, Virginia Commonwealth University Health System, Richmond (D.S.); Department of Internal Medicine, Division of Cardiology, University of Rochester Medical Center, NY (J.B.); and Department of Nephrology and Hypertension, Medizinische Hochschule Hannover, Hannover, Germany (H.H.).
authors.forename: John
authors.initials: J
authors.lastname: Bisognano
authors.affiliation: From the Department of Medicine, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (P.W.d.L., T.A., A.A.K.); CVRx Inc, Minneapolis, MN (E.L.); Division of Nephrology, Virginia Commonwealth University Health System, Richmond (D.S.); Department of Internal Medicine, Division of Cardiology, University of Rochester Medical Center, NY (J.B.); and Department of Nephrology and Hypertension, Medizinische Hochschule Hannover, Hannover, Germany (H.H.).
authors.forename: Hermann
authors.initials: H
authors.lastname: Haller
authors.affiliation: From the Department of Medicine, Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht, The Netherlands (P.W.d.L., T.A., A.A.K.); CVRx Inc, Minneapolis, MN (E.L.); Division of Nephrology, Virginia Commonwealth University Health System, Richmond (D.S.); Department of Internal Medicine, Division of Cardiology, University of Rochester Medical Center, NY (J.B.); and Department of Nephrology and Hypertension, Medizinische Hochschule Hannover, Hannover, Germany (H.H.).
authors.forename: Abraham A
authors.initials: AA
authors.lastname: Kroon
mesh_terms: D017704:Baroreflex / Q000502:physiology*; D001794:Blood Pressure / Q000502:physiology*; D004599:Electric Stimulation Therapy / Q000295:instrumentation*; D004567:Electrodes, Implanted; D004867:Equipment Design; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006973:Hypertension / Q000503:physiopathology / Q000628:therapy; D008297:Male; D008875:Middle Aged; D011311:Pressoreceptors / Q000502:physiology*; D013997:Time Factors; D016896:Treatment Outcome
keywords: hemodynamics; hypertension; pressoreceptors; sympathetic nervous system