Clinical outcome of electrical transcutaneous auricular vagal stimulation in patients with stable symptomatic chronic...

Chronic heart failure (CHF) is characterized by an autonomic imbalance of vagal activity and increased sympathetic activity. Low-level transcutaneous auricular vagus nerve stimulation (Ta-VNS) may be a safe complementary treatment option for CHF patients.

In this randomized clinical trial, a total of 13 patients with diagnosed CHF and reduced ejection fraction were randomized to receive either low-level Ta-VNS with electrodes applied in the triangular fossa of the ear (amplitude 1 mA, frequency 1 Hz for 40 min, followed by a 20-minute break) or sham intervention. The primary endpoint was an increase of 6-minutes walking distance assessed during cardiological screening and closing visits. Secondary endpoints included assessment of New York heart association (NYHA)-classification, a physical examination, electrocardiogram and blood sampling for n-terminal pro-brain natriuretic peptide (NT-proBNP)and C-reactive protein (CRP). Echocardiogram was performed at screening and adverse events were assessed at the closing visit.

A total of 12 patients completed the trial. 6-minute-walking-distance increased by 101.1 (94.6) metres in the transcutaneous auricular vagal nerve stimulation group, and by 7.2 (41.8) metres in the sham intervention group (p = 0.04). Concerning the secondary outcome parameters, including CRP and NT-proBNP, no difference was observed between groups. No adverse events were observed.

In patients with CHF, Ta-VNS effectively improved 6-minutes walking distance while no such effect was observed in the sham intervention group. Further investigation of this finding in a larger patient collective might be of interest.