Using HRV to Predict Success with Implanted Vagal Nerve Stimulators for Drug Resistent Epilepsy

Modern innovations for acupuncture — Ancient Medicine Made Modern: Scientific Solutions for Remarkable Results

This article achieves something that has always been on the back burner of my HRV project. That is, can we tell something about people’s likelihood to respond to treatment before we treat them, by analyzing their HRV? In my earliest research, I saw a correlation with patients’ stress response (LF/HF) on the treatment table with likelihood of clinical response. This paper asks a different question. It is established that vagal nerve stimulators don’t work on everyone. So they are asking whether we can tell something about the patients’ propensity to respond to an indwelling vagal nerve stimulator by their baseline HRV. Keep in mind, that this would extremely useful since vagal nerve stimulators have side effects and require surgery to implant them. But I’ve wondered the same thing about TAVNS. Can we tell whether non-invasive vagal nerve stimulators would be effective beforehand looking at their baseline HRV? Obviously, the downsides of just trying TAVNS are much less than implanted vagal nerve stimulators.

There are some counterintuitive results that I’m not sure what to make of. They said that non-reponders had lower RMSSD, pNN50, HF and TP than responders. That makes sense to me since it implies a higher sympathetic state with less resilience. But they also had lower VLF, LF and LF/HF which implies higher vagal activity.

Their previous study here.

Full article here.

2018 Mar 1;8(1):3856. doi: 10.1038/s41598-018-21669-3.

Preoperative Heart Rate Variability as Predictors of Vagus Nerve Stimulation Outcome in Patients with Drug-resistant Epilepsy.

Liu HY^1,², Yang Z¹, Meng FG^3,⁴, Guan YG⁵, Ma YS⁶, Liang SL⁷, Lin JL⁸, Pan LS⁷, Zhao MM⁹, Qu W¹, Hao HW¹, Luan GM⁵, Zhang JG⁴, Li LM^10,^11,^12,¹³.

Author information

Abstract

Vagus nerve stimulation (VNS) is an adjunctive treatment for drug-resistant epilepsy (DRE). However, it is still difficult to predict which patients will respond to VNS treatment and to what extent. We aim to explore the relationship between preoperative heart rate variability (HRV) and VNS outcome. 50 healthy control subjects and 63 DRE patients who had received VNS implants and had at least one year of follow up were included. The preoperative HRV were analyzed by traditional linear methods and heart rhythm complexity analyses with multiscale entropy (MSE). DRE patients had significantly lower complexity indices (CI) as well as traditional linear HRV measurements than healthy controls. We also found that non-responders₀ had significantly lower preoperative CI including Area 1-5, Area 6-15 and Area 6-20 than those in the responders₀ while those of the non-responders₅₀ had significantly lower RMSSD, pNN50, VLF, LF, HF, TP and LF/HF than the responders₅₀. In receiver operating characteristic (ROC) curve analysis, Area 6-20 and RMSSD had the greatest discriminatory power for the responders₀ and non-responders₀, responders₅₀ and non-responders₅₀, respectively. Our results suggest that preoperative assessment of HRV by linear and MSE analysis can help in predicting VNS outcomes in patients with DRE.