Kristen Sparrow • March 05, 2017
As some of my patients know, I’ve been using tVNS, or transcutaneous vagal nerve stimulation in some of my patients. I do it by stimulating the ear in the cymba concha region. Some patients have opted to take a device home with a custom electrode that I make for them. This paper corroborates the efficacy of this strategy. I have not seen the high percentage response to tVNS as they have seen. It is possible that since patients with tinnitus have a lower HRV to begin with compared to the general population, they show more dramatic results.
Transcutaneous vagal nerve stimulation (tVNS) might offer a targeted, patient-friendly, and low-cost therapeutic tool for tinnitus patients with sympathovagal imbalance.
Conventionally, VNS has been performed to treat severe epilepsy and depression with an electrode implanted to the cervical trunk of vagus nerve. This study investigated the acute effects of tVNS on autonomic nervous system (ANS) imbalance, which often occurs in patients with tinnitus-triggered stress.
This study retrospectively analysed records of 97 patients who had undergone ANS function testing by heart rate variability (HRV) measurement immediately before and after a 15-60 min tVNS stimulation.
The pre-treatment HRV recording showed sympathetic preponderance/reduced parasympathetic activity in about three quarters (73%) of patients. Active tVNS significantly increased variability of R-R intervals in 75% of patients and HRV age was decreased in 70% of patients. Either the variability of R-R intervals was increased or the HRV age decreased in 90% of the patients. These results indicate that tVNS can induce a shift in ANS function from sympathetic preponderance towards parasympathetic predominance. tVNS caused no major morbidity, and heart rate monitoring during the tVNS treatment showed no cardiac or circulatory effects (e.g. bradycardia) in any of the patients.