Effect of Exercise in OI

This study is ongoing, but not recruiting participants.
Information provided by (Responsible Party):
Italo Biaggioni, Vanderbilt University
ClinicalTrials.gov Identifier:
First received: October 9, 2008
Last updated: February 2, 2015
Last verified: February 2015

The main limitation patients with orthostatic intolerance (OI, or postural tachycardia syndrome, POTS) have to exercise is related to their increase in heart rate when standing. Main pharmacological treatment today is aimed at reducing heart rate with the use of betablockers (propanolol), this theoretically could also improve their exercise capacity; if their heart rate do not increase as much with the medication, they could exercise more. In addition, it has been suggested that in healthy volunteers subjected to head down tilt for 2 weeks (situation that produces a "simulated" transient POTS-like state) a single bout of intense exercise can improve orthostatic tolerance the day after exercising. The mechanisms involved in such response are not that clear but could be an increase in plasma volume already diminished in POTS patients. It seems likely that the same could be true for POTS patients.

The purpose of the present study are to pharmacologically improve the amount of exercise POTS patients can perform by reducing their baseline heart rate (specific aim 1) and to evaluate next day heart responses to an acute bout of intense exercise.

Therefore, the specific aims of this study are:

  1. To test the hypothesis that lowering heart rate response with propanolol will result in an increase in exercise capacity.
  2. To test the hypothesis that a single bout of exercise will result in an improvement in orthostatic tolerance the day after exercising.

Condition Intervention
Orthostatic Intolerance
Postural Tachycardia Syndrome
Drug: Propanolol
Drug: Placebo

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Official Title: Effects of Exercise in Orthostatic Intolerance

Resource links provided by NLM:

Further study details as provided by Vanderbilt University:

Primary Outcome Measures:
  • Maximal Oxygen Consumption Capacity (VO2 max) [ Time Frame: At the time of the actual intervention ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Heart rate in response to the intervention [ Time Frame: Day after intervention ] [ Designated as safety issue: No ]

Estimated Enrollment: 20
Study Start Date: November 2008
Estimated Study Completion Date: November 2016
Estimated Primary Completion Date: September 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Propanolol Drug: Propanolol
Propanolol 20 mg, given orally within 1 hour prior to exercising
Placebo Comparator: Placebo Drug: Placebo
Placebo, matching pill given orally within 1 hour prior to exercising

Detailed Description:
  • Subjects will be studied twice, once after receiving placebo and in a second occasion after receiving propanolol.
  • An exercise capacity test with estimation of maximal oxygen consumption (VO2 max) will be done within 1 hour of receiving a pill containing placebo and that will be in appearance identical to the one for propanolol. This test will be conducted on a stationary bicycle and the effort will be gradually increased while expired air is measured during exhaustive physical work. The test will last approximately 30 minutes and be conducted in Vanderbilt's Clinical Trial Center.
  • The day before and the day after the exercise test subjects will be asked to collect urine for 12 hours each time and to keep a record of how much liquid they ingest.
  • Posture study tests (measurements of heart rate and blood pressure taken while lying down and at intervals for up to 30 minutes while standing) will be done the day before and the day after the exercise test.

Ages Eligible for Study:   18 Years to 65 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Meet diagnostic criteria of POTS (Raj, et al., 2005)
  • Age between 18-65 years
  • Male and female are eligible (although the majority of patients POTS are female).
  • Able and willing to provide informed consent

Exclusion Criteria:

  • Presence of medical conditions that can explain postural tachycardia (e.g., dehydration, medications)
  • Pregnancy
  • Other factors which in the investigator's opinion would prevent the subject from completing the protocol.
  • Patients who are bedridden or chair-ridden.
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00770484

United States, Tennessee
Vanderbilt University Medical Center
Nashville, Tennessee, United States, 37232
Sponsors and Collaborators
Vanderbilt University
  More Information

No publications provided by Vanderbilt University

Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Italo Biaggioni, Professor of Medicine and Pharmacology, Vanderbilt University
ClinicalTrials.gov Identifier: NCT00770484     History of Changes
Other Study ID Numbers: 080722
Study First Received: October 9, 2008
Last Updated: February 2, 2015
Health Authority: United States: Institutional Review Board

Keywords provided by Vanderbilt University:
Beta blockers

Additional relevant MeSH terms:
Mitral Valve Prolapse
Neurocirculatory Asthenia
Orthostatic Intolerance
Postural Orthostatic Tachycardia Syndrome
Anxiety Disorders
Autonomic Nervous System Diseases
Cardiovascular Diseases
Heart Diseases
Heart Valve Diseases
Heart Valve Prolapse
Mental Disorders
Nervous System Diseases
Neurologic Manifestations
Primary Dysautonomias
Signs and Symptoms
Adrenergic Agents
Adrenergic Antagonists
Adrenergic beta-Antagonists
Anti-Arrhythmia Agents
Antihypertensive Agents
Cardiovascular Agents
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Pharmacologic Actions
Physiological Effects of Drugs
Therapeutic Uses
Vasodilator Agents

ClinicalTrials.gov processed this record on March 31, 2015