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Status unknownNCT00481806Updated May 10, 2013

Evaluating the Role of Thrombin in Saphenous Vein Graft Failure After Heart Bypass Surgery

An observational study in Coronary Artery Bypass and Thrombosis, sponsored by University of Arizona. Status unknown at 1 site in United States. Open to participants aged 18 Years to 90 Years. Per ClinicalTrials.gov, last updated 2013-05-10.

Sponsored by University of Arizona · Observational

The sponsor has not verified this record recently (last verified May 2013), so the status shown — last known as Recruiting — may be out of date.
Study type
Observational
Model
Case-only
Time perspective
Prospective
Enrollment
450
Ages
18 Years to 90 Years
Sex
All
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Study summary

Heart bypass surgery, also known as coronary artery bypass graft (CABG) surgery, creates a detour around the blocked part of a heart artery to restore blood supply to the heart muscle. The saphenous vein, located along the inside of the leg, is commonly used to create the bypass in a CABG surgery. An abnormal increase in the blood clotting protein thrombin may cause the saphenous vein graft to close up and eventually fail. This study will evaluate the relationship between thrombin levels and saphenous vein graft failures in people undergoing a CABG procedure.

Read the detailed description

The saphenous vein, which runs from the ankle to the groin along the inside of the leg, is commonly used as a graft for people undergoing a CABG surgery. The vein is removed from the leg and reattached to the heart to create a detour around the blocked part of a coronary artery. Following this procedure, many people are prescribed aspirin as a way to increase the chance that the graft procedure will be successful. However, saphenous vein graft failure may still occur in some people, indicating a need to understand why this happens and who might be at risk for graft failure. Thrombin, a protein involved in the blood clotting process, is somehow related to aspirin resistance, abnormalities in blood flow, and cell disruption within the saphenous vein, all factors thought to increase the risk of graft failure. The purpose of this study is to evaluate the likelihood that a burst in thrombin contributes to graft failure in people who have recently undergone a CABG procedure using the saphenous vein.

This study will enroll individuals undergoing CABG surgery at the University of Maryland. Prior to and immediately following surgery, an incision will be made in the skin and the time required for the blood to form a clot will be determined. During surgery, participants' blood vessels will be examined using imaging and cell analysis techniques. Blood collection will occur before surgery, immediately after surgery, and on Days 1, 3, and 30 following surgery. A portion of blood will be frozen for future analysis. An x-ray of the saphenous vein will be performed on Day 5 and again at a follow-up visit 6 to 12 months following surgery. Kidney function will be measured at both of these visits prior to the x-ray procedure. At the second visit, health and mental status questionnaires will be completed.

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Conditions studied

  • Coronary Artery Bypass
  • Thrombosis

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Keywords

  • Virchow's Triad
  • Thrombin
  • Graft Failure
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In context

Thrombosis

1,506 studies on the registry are indexed under Thrombosis; 238 are open to participants now.

This study's planned enrollment of 450 is above the median of 213 across 586 observational studies indexed under Thrombosis.

Browse Thrombosis studies →

Lead sponsor

University of Arizona is the lead sponsor of 466 studies on the registry; 87 are open to participants now.

Of its 47 completed or terminated interventional studies of FDA-regulated products, 29 (62%) have results posted.

Counted across the registry records on this site, refreshed daily.

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Who can participate

Ages eligible
18 Years to 90 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Non-probability sample

Study population

Male and female patients between the the age of 18-90 years belonging to all races will be enrolled in the study

Inclusion criteria

  • Scheduled for CABG surgery at University of Arizona University Medical Center (UMC)
  • For females, willing to use a reliable form of birth control for the duration of the study

Exclusion criteria

Exclusion Criteria:

  • Non-dermatologic allergy to intravenous (IV) radiographic contrast
  • Creatinine levels greater than 2.0 mg/dL
  • Pregnant
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Study design

Observational model
Case-only
Time perspective
Prospective
Enrollment
450 participants (estimated)
Biospecimen retention
Samples with dna
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What researchers measure

Primary outcomes

  1. Amplifying the severity of all three risk factors of Virchow's triad is expected to lead to a synergistic increase in regional thrombin formation

    Time frame: Measured at 5 years

  2. Pressure distention is the main stimulus that creates a loss of thrombin control within the SVG

    Time frame: Measured at 5 years

  3. Accurate tests of graft quality will be developed that provide rapid results for ready translation into clinical applications

    Time frame: Measured at 5 years

  4. Aprotinin or bivalirudin will effectively suppress thrombin generation and its effects within the highest risk grafts

    Time frame: Measured at 5 years

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Study locations

1 of 1 sites recruiting
  • University of Arizona College of Medicine
    Tucson, Arizona 85724, United States
    • Robert S. Poston, MD · Principal investigator
    Recruiting
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References and documents

Publications

  • Desai P, Kiani S, Thiruvanthan N, Henkin S, Kurian D, Ziu P, Brown A, Patel N, Poston R. Impact of the learning curve for endoscopic vein harvest on conduit quality and early graft patency. Ann Thorac Surg. 2011 May;91(5):1385-91; discussion 1391-2. doi: 10.1016/j.athoracsur.2011.01.079. PubMed 21524447 ↗
  • Poston RS, Tran R, Collins M, Reynolds M, Connerney I, Reicher B, Zimrin D, Griffith BP, Bartlett ST. Comparison of economic and patient outcomes with minimally invasive versus traditional off-pump coronary artery bypass grafting techniques. Ann Surg. 2008 Oct;248(4):638-46. doi: 10.1097/SLA.0b013e31818a15b5. PubMed 18936577 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 10, 2013, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
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Registry details

Key details

Study ID
NCT00481806
Lead sponsor
University of Arizona
Collaborators
University of Maryland, Baltimore County
Responsible party
Robert Poston (Chief, Division of Cardiothoracic Surgery, University of Arizona) — Principal investigator
First posted
Jun 4, 2007
Start date
Feb 2007
Primary completion
May 2013 (estimated)
Completion
Dec 2013 (estimated)
Last update
May 10, 2013

Study contacts

Robert S. Poston, MD
Contact
rposton@surgery.arizona.edu
520-626-7951
Robert S. Poston, MD
principal investigator · University of Arizona, Tucson
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is status unknown, as verified in May 2013. You cannot join it, but the record below documents what was studied.

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