Manometric Abnormalities in the Postural Orthostatic Tachycardia Syndrome: A Case Series

Abstract

Postural orthostatic tachycardia syndrome (POTS) is a rare disease that is believed to be mediated by dysautonomia. Gastrointestinal complaints in POTS patients are common and disturbing but not well characterized. We hypothesized that gastrointestinal dysmotility may be contributory to these symptoms. We studied 12 POTS patients who presented with gastrointestinal symptoms to a tertiary referral center. Gastrointestinal symptoms were quantified using a previously validated symptom questionnaire. All patients underwent gastroduodenal manometry (GDM); select patients also underwent further testing including esophageal manometry (EM), anorectal manometry (ARM), plain abdominal radiography (AXR), abdominal computed tomography (CT), gastric emptying studies (GES), and colonic transit time (CTT) studies. The four most common symptoms were bloating, constipation, abdominal pain, and nausea/vomiting, all experienced by greater than 70 % of patients. On GDM testing, 93 % of patients demonstrated signs of neuropathy, and the most common abnormalities observed included bursts of uncoordinated phasic activity in both fasting (59 %) and post-prandial (42 %) states, low contractility in the post-prandial state (67 %), and lack of post-prandial pattern (42 %). A total of 67 % of patients undergoing EM and 86 % of those undergoing ARM demonstrated abnormalities consistent with dysmotility. On AXR or CT, 58 % demonstrated either dilated intestinal loops or air-fluid levels. On CTT 80 % demonstrated delayed colonic transit, while on GES 60 % demonstrated delayed gastric emptying. In this cohort of POTS patients with gastrointestinal symptoms, there is a high prevalence of abnormal manometric and radiographic findings suggestive of dysmotility.