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D-dimer to Establish Duration of Anticoagulation After Venous Thromboembolism

This study has been completed.
Information provided by (Responsible Party):
GUALTIERO PALARETI, St. Orsola Hospital Identifier:
First received: December 9, 2005
Last updated: November 22, 2016
Last verified: November 2016
The optimal duration of oral anticoagulant treatment in patients with idiopathic venous thromboembolism is still uncertain. The present study addresses the possible role of the D-dimer test in assessing the need for continuation of anticoagulation.The study aims at assessing whether D-dimer assay may have a role in guiding the duration of anticoagulation in these patients

Condition Intervention Phase
Deep Vein Thrombosis
Pulmonary Embolism
Drug: Vitamin K antagonist (Coumarin anticoagulants)
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: D-dimer Test to Establish Duration of Anticoagulation After a First Idiopathic Episode of Venous Thromboembolism; the Prospective Randomized "Prolong" Study

Resource links provided by NLM:

Further study details as provided by St. Orsola Hospital:

Primary Outcome Measures:
  • Confirmed recurrent proximal deep vein thrombosis and/or pulmonary embolism at 18 months follow up
  • Confirmed major bleeding events at 18 months follow up

Estimated Enrollment: 600
Study Start Date: September 2002
Estimated Study Completion Date: September 2005
Primary Completion Date: December 2004 (Final data collection date for primary outcome measure)
Detailed Description:
This is a multicenter prospective follow-up study in patients with a first episode of symptomatic idiopathic venous thromboembolism (proximal deep vein thrombosis and/or pulmonary embolism) who are treated with vitamin K antagonists (either warfarin or acenocoumarol) for a minimum of 3 months. Eligible patients who give informed consent are instructed to immediately stop oral anticoagulation and refrain from taking any other antithrombotic drugs until the next visit, scheduled after 30 days. At that visit, venous blood is sampled to perform D-dimer assay and thrombophilia tests. D-dimers are assessed using the Clearview Simplify D-dimer assay (Agen Biomedical Limited, Brisbane, Australia). Patients with normal D-dimer results do not continue anticoagulation, whereas those with elevated D-dimer results are randomized using a computer program to either stop or resume anticoagulation with vitamin K antagonists (INR 2.0-3.0). All patients are followed-up for 18 months. The study outcome are the composite of confirmed recurrent venous thromboembolism and major bleeding events. All suspected outcome events and all deaths are evaluated by a central adjudication committee whose members are unaware of the D-dimer and thrombophilia results and of the group assignments.

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

Inclusion Criteria:

  • Age > 18 years
  • After a first documented idiopathic proximal deep vein thrombosis and/or pulmonary embolism
  • After at least 3 months of oral anticoagulation
  • After written informed consent

Exclusion Criteria:

  • If the Venous thromboembolism occurred:
  • during pregnancy or puerperium
  • after recent (i.e. within three months) fracture or plaster casting of a leg,
  • after immobilization with confinement to bed for three consecutive days
  • after surgery with general anesthesia lasting longer than 30 minutes
  • Patients with:
  • active cancer
  • antiphospholipid antibody syndrome
  • antithrombin deficiency
  • serious liver disease or renal insufficiency (creatininemia > 2 mg/dL),
  • other indications for anticoagulation or contraindications for this treatment
  • limited life expectation
  • Patients who live too far from the clinical center
  Contacts and Locations
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Please refer to this study by its identifier: NCT00264277

Dept. of Angiology & Blood Coagulation, University Hospital S. Orsola-Malpighi
Bologna, BO, Italy, 40138
Sponsors and Collaborators
St. Orsola Hospital
Study Chair: GUALTIERO PALARETI, MD Head of Dept. Angiology & Blood Coagulation, University Hospital S. Orsola-Malpighi, Bologna, Italy
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: GUALTIERO PALARETI, Professor, St. Orsola Hospital Identifier: NCT00264277     History of Changes
Other Study ID Numbers: PROLONG STUDY
Study First Received: December 9, 2005
Last Updated: November 22, 2016

Keywords provided by St. Orsola Hospital:
Venous Thromboembolism

Additional relevant MeSH terms:
Venous Thromboembolism
Pulmonary Embolism
Venous Thrombosis
Embolism and Thrombosis
Vascular Diseases
Cardiovascular Diseases
Lung Diseases
Respiratory Tract Diseases
Fibrin fragment D
Vitamin K
Antifibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action
Growth Substances
Physiological Effects of Drugs processed this record on April 28, 2017