Vanderbilt Clinical Trials

Hemodynamic Mechanisms of Abdominal Compression in the Treatment of Orthostatic Hypotension in Autonomic Failure

Purpose

Compression garments have been shown to be effective in the treatment of orthostatic hypotension in autonomic failure patients. The purpose of this study is to determine the hemodynamic mechanisms by which abdominal compression (up to 40 mm Hg) improve the standing blood pressure and orthostatic tolerance in these patients, and to compare them with those of the standard of care midodrine. The investigators will test the hypothesis that abdominal compression will blunt the exaggerated fall in stroke volume and the increase in abdominal vascular volume during head up tilt.

Conditions

Orthostatic Hypotension
Pure Autonomic Failure
Multiple System Atrophy
Autonomic Failure

Eligibility

Eligible Ages: Between 18 Years and 80 Years
Eligible Genders: All
Accepts Healthy Volunteers: No

Inclusion Criteria

Male and female patients, - between 18-80 yrs., - with neurogenic orthostatic hypotension associated with primary autonomic failure (Parkinson Disease, Multiple System Atrophy and Pure Autonomic Failure). Orthostatic hypotension will be defined as ≥20 mmHg decrease in systolic BP or ≥10 mmHg of diastolic BP within 3 minutes on standing associated with impaired autonomic reflexes determined by autonomic testing in the absence of other identifiable causes (Freeman et al., 2011). - Patients able and willing to provide informed consent.

Exclusion Criteria

Pregnancy. - Significant cardiac, renal or hepatic illness, or with contraindications to administration of pressor agents or external abdominal compression will be excluded. - Clinically unstable coronary artery disease, or major cardiovascular or neurological event in the past 6 months, and; other factors which in the investigator's opinion would prevent the subject from completing the protocol including clinically significant abnormalities in clinical, mental or laboratory testing

Study Design

Phase: Phase 1
Study Type: Interventional
Allocation: Randomized
Intervention Model: Crossover Assignment
Primary Purpose: Other
Masking: Single (Participant)

Arm Groups

Arm	Description	Assigned Intervention
Experimental Abdominal compression and placebo pill	Abdominal compression with an inflatable abdominal binder (up to 40 mmHg) during head up tilt, and placebo pill given 1 hour before the second head up tilt	Other: Abdominal compression Abdominal compression of 40 mmHg with a commercial inflatable cuff applied during head up tilt Other names: abdominal binder Drug: Placebo pill Placebo pill given 1 hour before the second heat up tilt
Sham Comparator Sham abdominal compression and placebo	Sham abdominal compression with an inflatable abdominal binder (~5 mmHg) during head up tilt, and placebo pill given 1 hour before the second head up tilt	Other: Sham abdominal compression Sham abdominal compression of 5 mmHg with a commercial inflatable cuff applied during head up tilt Other names: abdominal binder Drug: Placebo pill Placebo pill given 1 hour before the second heat up tilt
Experimental Abdominal compression and midodrine	Abdominal compression with an inflatable abdominal binder (up to 40 mmHg) during head up tilt, and midodrine 2.5-10 mg PO given 1 hour before the second head up tilt	Other: Abdominal compression Abdominal compression of 40 mmHg with a commercial inflatable cuff applied during head up tilt Other names: abdominal binder Drug: midodrine Midodrine single dose 2.5-10mg PO given 1 hour before the second head up tilt Other names: ProAmatine
Active Comparator Sham abdominal compression and midodrine	Sham abdominal compression with an inflatable abdominal binder (~5 mmHg) during head up tilt, and midodrine 2.5-10mg PO given 1 hour before the second head up tilt	Other: Sham abdominal compression Sham abdominal compression of 5 mmHg with a commercial inflatable cuff applied during head up tilt Other names: abdominal binder Drug: midodrine Midodrine single dose 2.5-10mg PO given 1 hour before the second head up tilt Other names: ProAmatine

Recruiting Locations

Vanderbilt University
Nashville, Tennessee 37232

Contact:
Emily C Smith, RN
615-875-1516
autonomics@vumc.org

More Details

Status: Recruiting
Sponsor: Vanderbilt University Medical Center

Study Contact

Bonnie K Black, RN
615-343-6862
autonomics@vumc.org

Detailed Description

Patients with autonomic failure are characterized by disabling orthostatic hypotension (low blood pressure on standing) due to severe impairment of the autonomic nervous system. Compression garments such as waist-high stockings and abdominal binders have been shown to improve orthostatic hypotension in these patients. The purpose of this study is to determine the hemodynamic mechanisms by which abdominal compression (up to 40 mm Hg) improve the standing blood pressure and orthostatic tolerance in these patients, and to compare them with those of the standard of care midodrine. The investigators will test the hypothesis that abdominal compression will blunt the exaggerated fall in stroke volume and the increase in abdominal vascular volume during head up tilt. This study will help us better understand the contribution of the abdominal veins to orthostatic hypotension and the mechanisms underlying this non-pharmacological therapeutic approach. Participants will be studied in a tilt table in two separate days in a randomized, crossover fashion with sham abdominal compression (~5 mmHg) and active compression (~40 mmHg).

Notice

Study information shown on this site is derived from ClinicalTrials.gov (a public registry operated by the National Institutes of Health). The listing of studies provided is not certain to be all studies for which you might be eligible. Furthermore, study eligibility requirements can be difficult to understand and may change over time, so it is wise to speak with your medical care provider and individual research study teams when making decisions related to participation.