Effect of Exercise in OI - Full Text View

Sponsored by:	Vanderbilt University
Information provided by:	Vanderbilt University
ClinicalTrials.gov Identifier:	NCT00770484

Purpose

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:

To test the hypothesis that lowering heart rate response with propanolol will result in an increase in exercise capacity.
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

Genetics Home Reference related topics: Brugada syndrome short QT syndrome

MedlinePlus related topics: Exercise and Physical Fitness Marijuana Mitral Valve Prolapse Mobility Aids

Drug Information available for: Propranolol hydrochloride Propranolol Dexpropranolol

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Treatment, Randomized, Double Blind (Subject, Investigator), Placebo Control, Crossover Assignment, Efficacy Study
Official Title:	Effects of Exercise in Orthostatic Intolerance

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 2012
Estimated Primary Completion Date:	November 2012 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Propanolol: Experimental	Drug: Propanolol Propanolol 20 mg, given orally within 1 hour prior to exercising
Placebo: Placebo Comparator	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.

Eligibility

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

Criteria

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.

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00770484

Locations

United States, Tennessee
Vanderbilt University Medical Center	Recruiting
Nashville, Tennessee, United States, 37232
Contact: Alfredo Gamboa, MD adcresearch@vanderbilt.edu
Sub-Investigator: Alfredo Gamboa, MD
Sub-Investigator: Luis Okamoto, MD
Sub-Investigator: Andre Diedrich, M.D. Ph.D.
Sub-Investigator: Ginnie Farley
Principal Investigator: Italo Biaggioni, MD

Sponsors and Collaborators

Vanderbilt University

More Information

No publications provided

Responsible Party:	Vanderbilt University ( Italo Biaggioni, M.D. Professor of Medicine and Pharmacology. )
Study ID Numbers:	080722
Study First Received:	October 9, 2008
Last Updated:	April 8, 2009
ClinicalTrials.gov Identifier:	NCT00770484 History of Changes
Health Authority:	United States: Institutional Review Board

Keywords provided by Vanderbilt University:

Exercise
Propanolol
Beta blockers

Study placed in the following topic categories:

Vasodilator Agents
Neurotransmitter Agents
Heart Diseases
Adrenergic Agents
Asthenia
Tachycardia
Cardiovascular Agents
Antihypertensive Agents
Prolapse
Heart Valve Diseases
Postural Orthostatic Tachycardia Syndrome

Anxiety Disorders
Propranolol
Mitral Valve Prolapse
Mental Disorders
Orthostatic Intolerance
Adrenergic beta-Antagonists
Adrenergic Antagonists
Anti-Arrhythmia Agents
Neurocirculatory Asthenia
Arrhythmias, Cardiac

Additional relevant MeSH terms:

Vasodilator Agents
Neurotransmitter Agents
Adrenergic Agents
Molecular Mechanisms of Pharmacological Action
Physiological Effects of Drugs
Pathologic Processes
Propranolol
Mental Disorders
Syndrome
Therapeutic Uses
Adrenergic beta-Antagonists
Cardiovascular Diseases
Anti-Arrhythmia Agents

Heart Valve Prolapse
Neurocirculatory Asthenia
Disease
Heart Diseases
Tachycardia
Cardiovascular Agents
Antihypertensive Agents
Pharmacologic Actions
Heart Valve Diseases
Anxiety Disorders
Mitral Valve Prolapse
Adrenergic Antagonists
Arrhythmias, Cardiac

ClinicalTrials.gov processed this record on May 06, 2009