Ear clip offers non-pharmacological treatment for postural tachycardia syndrome
A patient-administered therapy ear clip device effectively uses nerve stimulation to treat postural tachycardia syndrome (POTS), according to a late-breaking clinical trial at Heart Rhythm 2023 [1]. This may offer a new treatment option for patients, since there currently are no successful standard of care therapies for POTS.
"Treatment options that mitigate POTS symptoms can be hard to determine and are often unsuccessful. For patients who are suffering and looking for answers, it can be frustrating. Our trial set out to better understand whether noninvasive vagus nerve stimulation could be a novel solution that improves overall quality of life," explained Stavros Stavrakis, MD, PhD, FACC, FHRS, University of Oklahoma Health Sciences Center. "We are pleased to show the success of this novel noninvasive therapy and hope this trial offers an important step forward in considering this emerging treatment option."
POTS is a clinical syndrome usually characterized by frequent symptoms that occur when standing, such as light headedness or fatigue, an increased heart rate when moving from a seated to a standing position, and the absence of orthostatic hypotension [2]. More common in women than men, POTS can cause debilitating symptoms that are often exacerbated by everyday activities, and many patients suffering from POTS experience a decrease in quality of life [3]. There are currently no successful standard of care therapies for POTS.
This sham-controlled, double-blind, randomized, first-in-human clinical trial sought to examine the effect of low-level transcutaneous stimulation (LLTS) relative to sham stimulation on POTS over a two-month period. LLTS (20 Hz, 1 mA below the discomfort threshold) was delivered using an ear clip attached to either the tragus (active; n=12) or the ear lobe (sham; n=14) for one hour daily over a two-month period. Patients attached the ear clips themselves after individual training. Of the 26 enrolled patients, the mean age was 34±11 years (100% female; 81% Caucasian). Heart rates were monitored daily using wearable devices and postural tachycardia was assessed during the baseline and two-month visit. Heart rate variability (HRV) based on five minute ECG, serum cytokines, and anti-autonomic auto antibodies were measured at the respective time points.
Postural tachycardia (in the absence of blood pressure drop) was significantly less in the active arm compared to the sham arm at two months (postural increase in heart rate was 18±10 bpm vs. 32±14 bpm). Anti-autonomic auto antibodies (α1-AR and β1-AR) were lower in the active arm compared to the sham at two months. No device-related side effects were observed.
Additional analysis of continuous heart rate monitoring, HRV, and cytokine analysis is currently underway. The authors also said that further studies are needed to examine the long-term effects and optimize patient selection.