Acute Effects of Respiratory-Gated Auricular Vagal Afferent Nerve Stimulation (RAVANS) in the Modulation of Blood Pressure in Hypertensive Patients

In this study, we evaluate the acute effects of a novel, non-invasive, respiratory-gated auricular vagal afferent nerve stimulation (RAVANS) technique on arterial blood pressure levels in hypertensive patients. We consider data from 18 hypertensive subjects (53.6±6.3 years, 9 males) during three stimulation sessions where they received either sham, low-intensity, or medium-intensity stimulation in randomized order. Blood pressure was continuously collected during 15-minute baseline, stimulation, and recovery windows. Our statistical analysis shows that the percent decrease of median systolic blood pressure from baseline was significantly higher during RAVANS (medium-intensity) when compared to sham. Furthermore, a two-way ANOVA reveals a significant interaction between Intervention and Phase for changes in median systolic blood pressure. Post hoc testing reveals that this effect was driven by the Recovery Phase following RAVANS where median Systolic blood pressure significantly decreased in the last 5 minutes compared to sham. Our results indicate that exhalatory-gated RAVANS has acute modulatory effects on systolic blood pressure levels of hypertensive patients. Further longitudinal studies will be required to evaluate the therapeutic potential of the RAVANS electroceutical device.