RESUMO
BACKGROUND: Preclinical studies suggest that neuromodulation with thoracic spinal cord stimulation (SCS) improves left ventricular (LV) function and remodeling in systolic heart failure (HF). OBJECTIVE: The purpose of this study was to evaluate the safety and efficacy of a SCS system for the treatment of systolic HF. METHODS: We performed a prospective, multicenter pilot trial in patients with New York Heart Association (NYHA) class III HF, left ventricular ejection fraction (LVEF) 20%-35%, and implanted defibrillator device who were prescribed stable optimal medical therapy. Dual thoracic SCS leads were used at the T1-T3 level. The device was programmed to provide SCS for 24 hours per day (50 Hz at pulse width 200 µs). RESULTS: We enrolled 22 patients from 5 centers:17 patients underwent implantation of a SCS device and 4 patients who did not fulfill the study criteria served as nontreated controls. No deaths or device-device interactions were noted during the 6-month period in the 17 SCS-treated patients. Fifteen of 17 completed the efficacy endpoint assessments: composite score improved by 4.2 ± 1.3, and 11 patients (73%) showed improvement in ≥4 of 6 efficacy parameters. There was significant improvement in NYHA class (3.0 vs 2.1, P = .002; 13/17 improved); Minnesota Living with Heart Failure Questionnaire (42 ± 26 vs 27 ± 22, P = .026; 12/17 improved); peak maximum oxygen consumption (14.6 ± 3.3 vs 16.5 ± 3.9 mL/kg/min, P = .013; 10/15 improved); LVEF (25% ± 6% vs 37% ± 8%, P<.001; 14/16 improved); and LV end-systolic volume (174 ± 57 vs 137 ± 37 mL, P = .002; 11/16 improved) but not in N-terminal prohormone brain natriuretic peptide. No such improvements were observed in the 4 nontreated patients. CONCLUSION: The results of this first-in-human trial suggest that high thoracic SCS is safe and feasible and potentially can improve symptoms, functional status, and LV function and remodeling in patients with severe, symptomatic systolic HF.
