Spinal Cord Stimulation (SCS) in Refractory Angina

The study aims at assessing safety and efficacy of Spinal Cord Stimulation (SCS) for the treatment of refractory angina pectoris in a single blind, prospective, multicenter study. Sixty patients with refractory angina with new SCS device implantation will be randomized to one of three treatment groups: * paresthesic SCS; * subliminal SCS; * low (non effective) stimulation (control). Clinical follow-up will be done at 1 and 3 months. Control group patients will then be randomized to paresthesic SCS or subliminal SCS for another 3 months and the 2 groups will be reassessed at 6 months.