Investigating how leg vein distension affects blood pressure

The Venous Distension Reflex and Orthostatic Hypertension

Not applicable Interventional Milton S. Hershey Medical Center · NCT03496792

This study is testing how swelling in the leg veins affects blood pressure, especially when standing up, to help understand how the body keeps blood pressure steady during changes in position.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment30 (estimated)
Ages18 Years and up
SexAll
SponsorMilton S. Hershey Medical Center Academic / other
Locations1 site (Hershey, Pennsylvania)
Trial IDNCT03496792 on ClinicalTrials.gov

What this trial studies

This research aims to understand the impact of venous distension in the legs on blood pressure, particularly in relation to orthostatic hypertension. The study will utilize various interventions, including limb occlusion and negative pressure, to assess changes in muscle sympathetic nerve activity and mean arterial blood pressure. Participants will be categorized based on their blood pressure responses when standing versus supine, allowing for a detailed examination of the venous distension reflex. The findings could provide insights into the autonomic adjustments necessary for maintaining blood pressure during postural changes.

Who should consider this trial

Good fit: Ideal candidates include adults aged 18 and older with either elevated standing blood pressure or normal blood pressure responses.

Not a fit: Patients with chronic diseases, orthostatic hypotension, or those under 18 years old may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to improved management strategies for patients with orthostatic hypertension.

How similar studies have performed: While the specific approach of examining venous distension reflex in lower limbs is novel, related studies have shown promising results in understanding blood pressure regulation.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Are capable of giving informed consent
* Are of any race or ethnicity
* Are fluent in written and spoken English
* Whose history and physical exam did not uncover any exclusion criteria
* Are 18 years of age

For subjects with elevated standing BP

* Systolic BP (SBP) during standing is at least 10 mmHg \> the supine SBP
* Patients with a diagnosis of stage I hypertension without other chronic diseases may be INCLUDED

For normal subjects without elevated standing BP

* The change in SBP by standing is within ± 5 mmHg from the supine SBP
* Matched gender, similar age and BMI (within 10%) to participants with elevated standing BP
* Free of acute or chronic medical conditions

Exclusion Criteria:

* Age \< 18 years of age
* Are a pregnant or nursing woman
* Are a prisoner or institutionalized individual or unable to consent
* Have chronic diseases (e.g. heart, lung, neuromuscular disease, or cancer) other than stage I hypertension
* Have orthostatic hypotension or a history of syncope
* Current smoker
* History of blood clots

Where this trial is running

Hershey, Pennsylvania

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Blood Pressurevenous distension reflex
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.