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D-dimer Levels During and After Anticoagulation in Patients With a Previous Venous Thromboembolism: Effects on the Risk of Recurrence

This study has been completed.
ClinicalTrials.gov Identifier:
First Posted: December 15, 2005
Last Update Posted: September 5, 2012
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Italian Federation of Anticoagulation Clinics (FCSA)
Information provided by (Responsible Party):

The results of the Prolong study, currently submitted for publication, show that patients with a first unprovoked venous thromboembolic event who have altered D-dimer levels, measured one month after anticoagulation with vitamin K antagonists is stopped, have a high rate of recurrences (about 14%) and a prolongation of anticoagulation is effective in reducing significantly this rate. Those patients with normal D-dimer (about 60% of all patients examined) have a low rate of recurrences (about 5%) and likely a prolongation of anticoagulation in all these patients cannot be recommended.

In line with these results, the Prolong-Two study aims at assessing the predictive role for recurrence of D-dimer levels measured: a) during anticoagulation, b) one month after its withdrawal and c) periodically during follow up.

Patients with a first unprovoked venous thromboembolism (including proximal deep vein thrombosis of a leg and/or pulmonary embolism) which are treated with vitamin K antagonists for not less than 6 months are considered for the study. D-dimer assay is performed during anticoagulation and patients with altered results continue the anticoagulation for 6 more months. Those with normal D-dimer stop the anticoagulant treatment and are again examined one month later. Anticoagulation is resumed for 6 more months in those patients with abnormal D-dimer results but is permanently stopped in those with a normal assay. The latter patients are examined and D-dimer assay performed again every two months to evaluate the natural history of the assay after anticoagulation is stopped and the possible predictive value for recurrence of a change of the assay during follow-up from normal to abnormal results.

Condition Phase
Deep Vein Thrombosis Pulmonary Embolism Phase 4

Study Type: Observational
Study Design: Observational Model: Cohort
Time Perspective: Prospective
Official Title: A Multicentre, Prospective, Observational Study on the Predictive Role for Recurrence of D-dimer Levels Measured During and After Anticoagulation in Patients With a First Venous Thromboembolism Episode (the PROLONG-II Study)

Further study details as provided by GUALTIERO PALARETI, St. Orsola Hospital:

Biospecimen Retention:   Samples Without DNA
Plasma samples for D-dimer assays or other coagulation tests

Enrollment: 355
Study Start Date: August 2005
Study Completion Date: December 2008
Primary Completion Date: June 2008 (Final data collection date for primary outcome measure)

Information from the National Library of Medicine

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Ages Eligible for Study:   18 Years to 82 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Probability Sample
Study Population
Subjects with a single previous idiopathic venous thromboembolic event who stop anticoagulation

Inclusion Criteria

  • Age > 18 years
  • After a first documented idiopathic proximal deep vein thrombosis and/or pulmonary embolism
  • After at least 6 months of oral anticoagulation
  • After written informed consent

Exclusion Criteria:

  • Age > 82 y
  • Recurrent venous thromboembolism
  • 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
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT00266045

Dept. Angiology & Blood Coagulation; Azienda Ospedaliero-Universitaria di Bologna, Policlinico S. Orsola-Malpighi
Bologna, BO, Italy, 40138
Sponsors and Collaborators
St. Orsola Hospital
Italian Federation of Anticoagulation Clinics (FCSA)
Study Chair: Gualtiero Palareti, MD Dept. Angiology & Blood Coagulation, University Hospital S. Orsola-Malpighi, Bologna
  More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: GUALTIERO PALARETI, Prof. Gualtiero Palareti, St. Orsola Hospital
ClinicalTrials.gov Identifier: NCT00266045     History of Changes
Other Study ID Numbers: PROLONG-TWO STUDY
First Submitted: December 13, 2005
First Posted: December 15, 2005
Last Update Posted: September 5, 2012
Last Verified: August 2012

Keywords provided by GUALTIERO PALARETI, St. Orsola Hospital:
Deep Vein Thrombosis
Pulmonary Embolism
Duration of Anticoagulation
Vitamin K Antagonists

Additional relevant MeSH terms:
Venous Thromboembolism
Pulmonary Embolism
Venous Thrombosis
Embolism and Thrombosis
Vascular Diseases
Cardiovascular Diseases
Disease Attributes
Pathologic Processes
Lung Diseases
Respiratory Tract Diseases
Fibrin fragment D
Antifibrinolytic Agents
Fibrin Modulating Agents
Molecular Mechanisms of Pharmacological Action