Dose-Optimization of Respiratory-Gated Auricular Vagal Afferent Nerve Stimulation (RAVANS) for Blood Pressure Modulation in Hypertensive Patients

The objective of this study was to determine the optimal frequency of respiratory-gated auricular vagal afferent nerve stimulation (RAVANS) for the modulation of blood pressure in hypertensive patients.Twelve hypertensive subjects (52.5±6.0 years, 8 females) underwent five randomized stimulation sessions, during which they received exhalatory-gated stimulation at frequencies of 2, 10, 25, and 100 Hz or sham stimulation. A continuous blood pressure signal was collected during a 30-minute stimulation period and a 10-minute recovery period using a Finometer device (Finapress Medical System, the Netherlands). LabChart (ADInstruments, Colorado Springs, CO, USA) was used to process and compute blood pressure responses.A significantly greater reduction of systolic blood pressure values during stimulation was observed in the 100 Hz session compared to sham (p=0.02). In addition, significant reductions in diastolic blood pressure (p=0.04) and mean arterial pressure (p=0.04) values were observed during RAVANS stimulation compared to baseline during the 100 Hz session. Evaluation of other stimulation frequencies did not reveal significant results.RAVANS exhibits a frequency-dependent effect on the modulation of arterial blood pressure levels of hypertensive subjects.