title: Autonomic Evaluation of Patients With Gastroparesis and Neurostimulation: Comparisons of Direct/Systemic and Indirect/Cardiac Measures.
abstract: BACKGROUND
  Disorders 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.
  
  
  METHODS
  We 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.
  
  
  RESULTS
  Both 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.
  
  
  CONCLUSIONS
  Both 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.
authors: Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, KY, USA.
authors: Abigail
authors: A
authors: Stocker
authors: Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, KY, USA.
authors: Thomas L
authors: TL
authors: Abell
authors: Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, KY, USA.
authors: Hani
authors: H
authors: Rashed
authors: Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, KY, USA.
authors: Archana
authors: A
authors: Kedar
authors: Division of Gastroenterology, Hepatology and Nutrition, University of Louisville, Louisville, KY, USA.
authors: Ben
authors: B
authors: Boatright
authors: Division of Gastroenterology and Hepatology, Department of Medicine, Johns Hopkins University, Baltimore, MD, USA.
authors: Jiande
authors: J
authors: Chen
keywords: Autonomic nervous system; Gastroparesis; Heart rate variability