Aims In chronic heart failure (CHF), reduced vagal activity correlates with increased mortality and acute decompensation. Experimentally, chronic vagus nerve stimulation (VNS) improved left ventricular (LV) function and survival; clinically, it is used for the treatment of drug-refractory epilepsy. We assessed safety and tolerability of chronic VNS in symptomatic CHF patients, using a novel implantable nerve stimulation system. The secondary goal was to obtain preliminary data on clinical efficacy. Methods and resultsThis multi-centre, open-label phase II, two-staged study (8-patient feasibility phase plus 24-patient safety and tolerability phase) enrolled 32 New York Heart Association (NYHA) class IIIV patients [age 56 ± 11 years, LV ejection fraction (LVEF) 23 ± 8]. Right cervical VNS with CardioFit (BioControl Medical) implantable system started 24 weeks after implant, slowly raising intensity; patients were followed 3 and 6 months thereafter with optional 1-year follow-up. Overall, 26 serious adverse events (SAEs) occurred in 13 of 32 patients (40.6), including three deaths and two clearly device-related AEs (post-operative pulmonary oedema, need of surgical revision). Expected non-serious device-related AEs (cough, dysphonia, and stimulation-related pain) occurred early but were reduced and disappeared after stimulation intensity adjustment. There were significant improvements (P <0.001) in NYHA class quality of life, 6-minute walk test (from 411 ± 76 to 471 ± 111 m), LVEF (from 22 ± 7 to 29 ± 8), and LV systolic volumes (P 0.02). These improvements were maintained at 1 year. ConclusionsThis open-label study shows that chronic VNS in CHF patients with severe systolic dysfunction may be safe and tolerable and may improve quality of life and LV function. A controlled clinical trial appears warranted.
- Autonomic nervous system
- Heart failure
- Non-pharmacologic therapy
ASJC Scopus subject areas
- Cardiology and Cardiovascular Medicine