Effectiveness of Bridging Anticoagulation for Surgery (The BRIDGE Study)

This study is currently recruiting participants. (see Contacts and Locations)
Verified April 2014 by Duke University
Sponsor:
Collaborator:
Information provided by (Responsible Party):
Duke University
ClinicalTrials.gov Identifier:
NCT00786474
First received: November 5, 2008
Last updated: April 3, 2014
Last verified: April 2014
  Purpose

Blood thinners, such as warfarin, prevent blood clots from forming, thereby reducing the risk of a stroke or heart attack. When people undergo surgery or certain procedures, they must stop using warfarin to prevent too much bleeding during and after the surgery or procedure. Some doctors prescribe a different blood thinner, one that works more quickly and wears off more quickly, to bridge the gap between starting and stopping warfarin. However, this short-term treatment is expensive, may increase the risk of bleeding, and has not been proven effective. This study will determine whether a bridging blood thinner called dalteparin is helpful or harmful for people with atrial fibrillation who stop taking warfarin in preparation for surgery or a procedure.


Condition Intervention Phase
Arterial Thromboembolic Events
Atrial Fibrillation
Drug: Placebo
Drug: Dalteparin
Phase 3

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Safety/Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator)
Primary Purpose: Treatment
Official Title: Bridging Anticoagulation in Patients Who Require Temporary Interruption of Warfarin Therapy for an Elective Invasive Procedure or Surgery

Resource links provided by NLM:


Further study details as provided by Duke University:

Primary Outcome Measures:
  • Arterial thromboembolic events, defined as an ischemic stroke, transient ischemic attack, or systemic embolism [ Time Frame: Measured throughout the study ] [ Designated as safety issue: Yes ]
  • Major bleeding, symptomatic bleeding associated with transfusion of more than two units of packed red blood cells or whole blood, or death [ Time Frame: Measured throughout the study ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:
  • Acute myocardial infarction, deep vein thrombosis, or pulmonary embolism [ Time Frame: Measured throughout the study ] [ Designated as safety issue: Yes ]
  • Minor bleeding [ Time Frame: Measured throughout the study ] [ Designated as safety issue: Yes ]

Estimated Enrollment: 2526
Study Start Date: July 2009
Estimated Study Completion Date: March 2015
Estimated Primary Completion Date: January 2015 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Placebo Comparator: Placebo Drug: Placebo
Normal saline solution, dosage determined by weight, self-administered by patient twice a day
Experimental: Dalteparin Drug: Dalteparin
Low molecular weight heparin (LMWH), dosage determined by weight, self-administered by patient twice a day
Other Name: Fragmin

Detailed Description:

Approximately 2 million people in North America take the anticoagulant warfarin to prevent stroke, heart attack, and other events related to blood clots. Warfarin needs to be stopped before a person undergoes surgery or certain procedures because it can cause dangerous amounts of bleeding during and after surgery. Some doctors give a low molecular weight heparin (LMWH) to patients during the 2-week period when participants are without the effects of warfarin. The LMWH has the same effect as warfarin, but it acts and then leaves the system more quickly than warfarin. However, the LMWH is expensive, may increase the risk of bleeding, and has not been proven effective. This study will determine the safety and efficacy of an LMWH in adults with atrial fibrillation who stop warfarin in preparation for surgery.

Participation in this study will last between 36 and 67 days. Participation will involve nine points of contact with researchers, at least two of which will be in-person visits at the research clinic. The others will be conducted by phone. All points of contact will include assessments on possible bleeding and any new symptoms. The first two of these points of contact, will take place at the signing of the informed consent, which will involve a screening of medical records and random assignment of participants to receive either the LMWH dalteparin or placebo. Participants will self-administer a subcutaneous injection of their assigned treatment twice a day for 3 days before the surgery or procedure and for 6 days after. During the course of the study, when participants visit their primary physicians for regularly scheduled appointments, it will be recommended that they undergo two international normalized ratio (INR) tests of blood clotting ability between day 2 and 10 after the surgery or procedure. The remaining seven points of contact will occur sometime between the day before surgery and 37 days after surgery. One of the in-person visits will occur within the first week after surgery and will include assessments on possible bleeding, any new symptoms, and INR results.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Receiving warfarin therapy for at least 3 months, administered to achieve an international normalized ratio (INR) range of 2.0 to 3.0
  • Requiring temporary interruption of warfarin for pre-specified elective procedure or surgery
  • Presence of one of the following conditions:

    1. Chronic (permanent or paroxysmal) nonvalvular atrial fibrillation, confirmed by at least one prior electrocardiography recording or pacemaker or acid citrate dextrose (ACD) interrogation
    2. Chronic (permanent or paroxysmal) valvular atrial fibrillation with evidence of mitral valvular heart disease, confirmed by the same criteria as nonvalvular atrial fibrillation
  • Presence of at least one of the following major stroke risk factors:

    1. Older than 75 years of age
    2. Hypertension
    3. Diabetes mellitus
    4. Congestive heart failure or left ventricular dysfunction
    5. Previous ischemic stroke, systemic embolism, or transient ischemic attack (TIA)

Exclusion Criteria:

  • Any mechanical prosthetic heart valve
  • Stroke (ischemic or hemorrhagic), systemic embolism, or TIA within the past 12 weeks
  • Venous thromboembolism (deep vein thrombosis and/or pulmonary embolism) within past 12 weeks
  • Major bleeding within the past 6 weeks
  • Severe renal insufficiency, measured through a calculated creatinine clearance of less than 30 mL/min
  • Thrombocytopenia
  • Life expectancy less than 1 month
  • Condition that impairs compliance with trial protocol, such as cognitive impairment, an uncontrolled psychiatric condition, or geographic inaccessibility
  • Pregnancy
  • Allergy to heparin or history of heparin-induced thrombocytopenia
  • Having one of the following surgeries or procedures during warfarin interruption:

    1. Cardiac surgery, such as coronary artery bypass or heart valve replacement
    2. Neurosurgery that is intracranial or intraspinal, such as tumor resection or aneurysm repair
    3. High-risk non-surgical procedures, such as brain biopsy
  • Other surgical or non-surgical procedure that, at the discretion of the surgeon, precludes administration of therapeutic-dose low molecular weight heparin (LMWH) at any time in the post-procedure period
  • More than one surgery planned during the trial period
  • Prior participation in this trial
  Contacts and Locations
Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the Contacts provided below. For general information, see Learn About Clinical Studies.

Please refer to this study by its ClinicalTrials.gov identifier: NCT00786474

Contacts
Contact: Wanda G. Parker, RN, MSN 919-668-8589 parke010@dcri.duke.edu

Locations
United States, North Carolina
Duke Clinical Research Institute Recruiting
Durham, North Carolina, United States, 27715
Sponsors and Collaborators
Duke University
Investigators
Principal Investigator: Thomas L. Ortel, MD Duke University
Principal Investigator: Victor Hasselblad, PhD Duke Clinical Research Institute
  More Information

No publications provided by Duke University

Additional publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Duke University
ClinicalTrials.gov Identifier: NCT00786474     History of Changes
Other Study ID Numbers: Pro00017344, 1U01HL086755-01A1, 1U01HL087229
Study First Received: November 5, 2008
Last Updated: April 3, 2014
Health Authority: United States: Federal Government
United States: Institutional Review Board

Keywords provided by Duke University:
Bridging Anticoagulation

Additional relevant MeSH terms:
Atrial Fibrillation
Thromboembolism
Embolism
Arrhythmias, Cardiac
Heart Diseases
Cardiovascular Diseases
Pathologic Processes
Embolism and Thrombosis
Vascular Diseases
Thrombosis
Dalteparin
Heparin, Low-Molecular-Weight
Anticoagulants
Hematologic Agents
Therapeutic Uses
Pharmacologic Actions
Fibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Cardiovascular Agents

ClinicalTrials.gov processed this record on July 22, 2014