title: Spinal cord stimulation therapy for patients with refractory angina who are not candidates for revascularization.
abstract: OBJECTIVE
  The aim of this study was to evaluate the safety and efficacy of spinal cord stimulation (SCS) for refractory angina.
  
  
  METHODS
  This multicenter, randomized, single-blind, controlled trial evaluated SCS in two patient groups: high stimulation (HS) (treatment) and low stimulation (LS) (control). The HS group controlled SCS with a programmer for a minimum of two hours four times daily. The LS group received SCS therapy above the paresthesia threshold for one min once daily. The primary efficacy endpoint was number of angina attacks recorded by patients at six months. The primary safety endpoint was the major adverse cardiac event (MACE) rate at six months.
  
  
  RESULTS
  Due to slow enrollment, a futility analysis was performed, resulting in early termination of the study. Sixty-eight patients were randomized after implantation. Mean change in angina attacks per day from baseline to six months was -1.19 ± 2.13 (HS) and -1.29 ± 1.66 (LS). The difference from baseline was significant within each group (both p < 0.001) but not between groups (p = 0.45). Total exercise time and time to angina onset increased significantly from baseline to six months within each group (both p = 0.02 and 0.002) but not between groups (p = 0.52 and 0.51). MACE was similar between groups.
  
  
  CONCLUSIONS
  Although this study was terminated early, the results obtained at six months suggest that SCS (HS) is not more effective than the control (LS) in patients with refractory angina.
authors.affiliation: Indiana University School of Medicine, Indianapolis, IN 46202-4800, USA. dzipes@iupui.edu
authors.forename: Douglas P
authors.initials: DP
authors.lastname: Zipes
authors.forename: Nelson
authors.initials: N
authors.lastname: Svorkdal
authors.forename: Daniel
authors.initials: D
authors.lastname: Berman
authors.forename: Richard
authors.initials: R
authors.lastname: Boortz-Marx
authors.forename: Timothy
authors.initials: T
authors.lastname: Henry
authors.forename: Amir
authors.initials: A
authors.lastname: Lerman
authors.forename: Edgar
authors.initials: E
authors.lastname: Ross
authors.forename: Michael
authors.initials: M
authors.lastname: Turner
authors.forename: Christopher
authors.initials: C
authors.lastname: Irwin
mesh_terms: D000368:Aged; D000787:Angina Pectoris / Q000628:therapy*; D002170:Canada; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016037:Single-Blind Method; D062187:Spinal Cord Stimulation / Q000009:adverse effects*; D016896:Treatment Outcome; D014481:United States