Autonomic Evaluation of Patients With Gastroparesis and Neurostimulation: Comparisons of Direct/Systemic and Indirect/Cardiac Measures

Abstract

BackgroundDisorders of nausea, vomiting, abdominal pain, and related problems often are manifestations of gastrointestinal, neuromuscular, and/or autonomic dysfunction. Many of these patients respond to neurostimulation, either gastric electrical stimulation or electroacupuncture. Both of these therapeutic techniques appear to influence the autonomic nervous system which can be evaluated directly by traditional testing and indirectly by heart rate variability.MethodsWe studied patients undergoing gastric neuromodulation by both systemic autonomic testing (39 patients, six males and 33 females, mean age 38 years) and systemic autonomic testing and heart rate variability (35 patients, seven males and 28 females, mean age 37 years) testing before and after gastric neuromodulation. We also performed a pilot study using both systemic autonomic testing and heart rate variability in a small number of patients (five patients, all females, mean age 48.6 years) with diabetic gastroparesis at baseline to compare the two techniques at baseline. Systemic autonomic testing and heart rate variability were performed with standardized techniques and gastric electrical stimulation was performed as previously described with electrodes implanted serosally in the myenteric plexus.ResultsBoth systemic autonomic testing and heart rate variability measures were often abnormal at baseline and showed changes after gastric neuromodulation therapy in two groups of symptomatic patients. Pilot data on a small group of similar patients with systemic automatic nervous measures and heart rate variability showed good concordance between the two techniques.ConclusionsBoth traditional direct autonomic measures and indirect measures such as heart rate variability were evaluated, including a pilot study of both methods in the same patient group. Both appear to be useful in evaluation of patients at baseline and after stimulation therapies; however, a future full head-to-head comparison is warranted.

Open‐label pilot study: Non‐invasive vagal nerve stimulation improves symptoms and gastric emptying in patients with idiopathic gastroparesis

“…Both diabetic and idiopathic gastroparesis are associated with autonomic dysfunction, which our baseline AFT confirmed. Although long‐term GES and implanted VNS can improve autonomic function, short‐term nVNS did not improve cardiovascular dysautonomia or autonomic symptoms in our gastroparesis cohort. Whether this was due to underpowering, duration of nVNS, differential vagal fiber engagement, or dosing (continuous high‐frequency/low‐energy pulses) is difficult to ascertain.…”

Gastroparesis syndromes: Response to electrical stimulation

“…Discussion of subgroup profiling of hormonal and cytokine data showed some differences between patient diagnostic groups and subgroups, as was the analysis of comorbidities by all patients and by subgroups …”

“…Discussion of subgroup profiling of hormonal and cytokine data showed some differences between patient diagnostic groups and subgroups, as was the analysis of comorbidities by all patients and by subgroups. 10,20,21 Regarding effects of GES on metabolic control, a recent study done by Lebovitz in type II DM patients who were treated with GES In addition, a high-frequency/low-energy GES treatment regimen in DM Gp patients showed a significant lowering of HbA1c from 8.5% to 6.5% over a period of 1 year. 25 Thus, the exact mechanism of HbA1c reduction after GES therapy is yet to be fully explained; we could speculate that an increase in GLP-1 post-GES might be one of the reasons for improved glycemic control with long-term GES.…”

“…Autonomic measures (standard autonomic testing and heart rate variability) Autonomic nervous system functions were measured by a standard technology (standard autonomic testing) and by heart rate variability. 10,11 Standard autonomic function testing In this autonomic testing, we used a custom module connected to a commercial recorder (ACEM; Sandhill Scientific/Diversatek, Milwaukee, WI, USA), and results were scored manually and reviewed by two investigators, one of whom was blinded. The values recorded from this standard noninvasive autonomic evaluation were carried out previously described into two main components: cardiovagal arch and sympathetic-adrenergic arch functions.…”

Nausea and Vomiting

“…After gastric neuromodulation, changes in autonomic testing, including an increase in cholinergic function and decrease in sympathetic function, were noted. It was proposed that gastric neuromodulation may work via modulation of the ANS [174].…”