Abstract 2412: Chronic Vagus Nerve Stimulation in Patients with Chronic Heart Failure is Feasible and Appears Beneficial
Introduction Enhancement of vagal nerve activity has a strong experimental rationale as a potential therapeutic approach to patients with severe Congestive Heart Failure (CHF). The CardioFit (BioControl Medical, Ltd.) is an implantable system capable of delivering chronic vagus nerve stimulation (CVNS) synchronized with the heart beat via a multipolar stimulation lead.
Methods Twenty-nine patients with stable CHF, NYHA class II–IV, LVEF ≤ 35% on optimal medical therapy were enrolled and successfully implanted in a 7-site international 6-month safety and efficacy pilot study. Optimization of CVNS parameters occurred during a four week run-in period, two to four weeks post-implantation.
Results Twenty subjects (mean age 57 years, range 30 –75; ischemic etiology in 70%; prior ICD in 50%) completed six-month follow-up; one NYHA class IV subject died due to worsening HF two months after implantation. At 6-months, 14 subjects had improved their NYHA class, and 6 remained stable. A significant improvement (p < 0.05) was found in the subjects’ quality of life (MLwHF® questionnaire); exercise capacity (6-minute walk test; see graph); and blindly evaluated LV ejection fraction (from 24 ± 2% to 29 ± 2%). The most commonly reported transient adverse events were expected side-effects of CVNS such as pain at cuff site (n = 6), cough (n = 7), and voice alteration (n = 5), which were resolved by optimizing stimulation parameters.
Conclusions Chronic Vagus Nerve Stimulation in patients with advanced heart failure is feasible and appears to be well tolerated and safe. Initial data suggest a favorable trend of clinical outcomes. At this point a large scale randomized controlled study is warranted.