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Endothelial Function in Lower Extremity Bypass Grafts

This study has been completed.
Information provided by (Responsible Party):
Joshua A. Beckman, MD, Brigham and Women's Hospital Identifier:
First received: September 24, 2008
Last updated: April 17, 2017
Last verified: April 2017
This study will determine whether or not saphenous vein [arterial] bypass grafts in the leg relax in response to increases in blood flow.

Condition Intervention
Peripheral Arterial Disease
Drug: L-N^G monomethyl arginine (L-NMMA)

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: Outcomes Assessor
Masking Description:
Investigators who analyzed the results of vascular function testing were blinded to the participant identity.
Primary Purpose: Basic Science
Official Title: Endothelial Function in Lower Extremity Bypass Grafts

Further study details as provided by Brigham and Women's Hospital:

Primary Outcome Measures:
  • Change From Baseline in Saphenous Vein Bypass Graft Vasodilation [ Time Frame: Single visit study ]
    Flow-mediated, endothelium-dependent vasodilation was determined by comparing baseline vein graft diameter with vein graft diameter as measured after deflation of a 2.5-inch wide sphygmomanometric cuff that had been inflated to suprasystolic pressure for 5 minutes. The cuff was never placed directly over the graft. Vasodilation of the vein graft was determined by acquiring images at 1 minute after cuff deflation.

Enrollment: 19
Study Start Date: April 2006
Study Completion Date: December 2009
Primary Completion Date: December 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1
ultrasound imaging of saphenous vein bypass graft following an ischemic stimulus, administration of sublingual nitroglycerin and intravenous administration of L-NMMA.
Drug: L-N^G monomethyl arginine (L-NMMA)
L-NMMA was infused at a dose of 1 mg/kg over 10 minutes to competitively inhibit the production of nitric oxide. Ultrasound imaging of the saphenous vein [arterial] bypass at baseline, and following an ischemic stimulus, administration of sublingual nitroglycerin, and intravenous administration of L-NMMA.

Detailed Description:
Subjects who have undergone saphenous vein [arterial] bypass grafts from the femoral to above-knee popliteal artery will undergo ultrasound imaging at rest, and again after 5 minutes of blood pressure cuff occlusion of the calf. (at 1 minute and 15 minutes) Subjects will then be given sub-lingual nitroglycerin, and repeat ultrasound will be performed 3 minutes later. Following 10 minutes of rest, subjects will be given intravenous L-NMMA, a specific nitric oxide inhibitor, to help determine the responsible agent of the vein graft flow mediated dilation.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Adults who have undergone femoral artery to above-knee popliteal artery saphenous vein bypass grafts

Exclusion Criteria:

  • Amputation beyond the toes
  • Critical limb ischemia defined as rest pain, non-healing ulceration or gangrene
  • Pregnancy
  Contacts and Locations
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Please refer to this study by its identifier: NCT00759707

United States, Massachusetts
Brigham and Women's Hospital
Boston, Massachusetts, United States, 02115
Sponsors and Collaborators
Brigham and Women's Hospital
Principal Investigator: Joshua A. Beckman, M.D. Brigham and Women's Hospital
  More Information

Responsible Party: Joshua A. Beckman, MD, Associate Professor of Medicine, Harvard Medical School, Brigham and Women's Hospital Identifier: NCT00759707     History of Changes
Other Study ID Numbers: 2006P-000424
Study First Received: September 24, 2008
Results First Received: December 8, 2016
Last Updated: April 17, 2017
Individual Participant Data  
Plan to Share IPD: No

Keywords provided by Brigham and Women's Hospital:
saphenous vein bypass grafts
flow-mediated vasodilation

Additional relevant MeSH terms:
Peripheral Arterial Disease
Peripheral Vascular Diseases
Arterial Occlusive Diseases
Vascular Diseases
Cardiovascular Diseases
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action processed this record on May 25, 2017