This trial is active, not recruiting.

Conditions postural tachycardia syndrome, orthostatic tachycardia, orthostatic intolerance
Treatment normal saline (0.9%)
Sponsor Vanderbilt University
Collaborator National Center for Research Resources (NCRR)
Start date February 2007
End date December 2018
Trial size 30 participants
Trial identifier NCT00581633, 061230, K23RR020783, P01HL056693, UL1RR024975


The investigators will test the hypothesis that patients with chronic orthostatic intolerance or postural orthostatic tachycardia syndrome (OI or POTS) will be unable to conserve urinary sodium as compared to healthy control subjects.

United States No locations recruiting
Other countries No locations recruiting

Study Design

Intervention model single group assignment
Primary purpose diagnostic
Masking no masking
saline infusion for sodium loading
normal saline (0.9%)
liter normal saline over 30 minutes x 1 dose

Primary Outcomes

Urinary Na excretion
time frame: 24h and then hourly post saline load

Secondary Outcomes

Catecholamine levels
time frame: 1 day

Eligibility Criteria

All participants from 18 years up to 65 years old.

Inclusion Criteria: - Diagnosed with orthostatic intolerance by Vanderbilt Autonomic Dysfunction Center (or healthy control subject) Exclusion Criteria: - Overt or acute cause for orthostatic tachycardia - Hypertension (BP>145/95 or need for anti-hypertensive medications) - QRS duration > 120 msec on EKG - Pregnancy

Additional Information

Official title Acute Renal Salt Handling in Orthostatic Intolerance
Principal investigator Satish R Raj, MD MSCI
Description Patients with chronic OI appear to be hypovolemic with abnormalities in hormones that regulate salt & water handling. Increases in dietary salt have salutary effects on orthostatic tolerance in a physiological laboratory. The infusion of intravenous saline acutely decreased heart rate in this patient population. Preliminary data from Vanderbilt suggests abnormal salt handling in patients with chronic OI in a few patients. These data need to be confirmed and a better understanding of sodium handling in response to acute salt loads is required in these patients.
Trial information was received from ClinicalTrials.gov and was last updated in March 2017.
Information provided to ClinicalTrials.gov by Vanderbilt University Medical Center.