MDA D-Dimer / Recurrent DVT Study

A Cohort Study Evaluating the Safety of a Diagnostic Strategy Involving D-Dimer and Compression Ultrasonography in Patients With Suspected Recurrent Deep Vein Thrombosis

To determine whether treatment and further investigation can be safely withheld in patients who present with suspected recurrent deep vein thrombosis (DVT) and have either a (i) negative D-Dimer or (ii) a positive D-Dimer with normal serial compression ultrasound.

Inclusion Criteria:

• Age 18 or older
• Currently suspected for recurrent DVT
• Has a prior history of objectively documented DVT or PE

Exclusion Criteria:

• Comorbid condition limiting survival to less than 3 months
• History of hypersensitivity to contrast medium
• Renal dysfunction with a creatinine of > 150 mcmol/L
• Treatment with full-dose therapeutic unfractionated or low molecular weight heparin that was initiated 24 hours or more prior to eligibility assessment
• Pregnancy or lactation
• Symptomatic for pulmonary embolism
• Absence of symptoms within five days prior to presentation
• Participation in another trial precluding the use of the diagnostic algorithm in this study
• Geographically inaccessible for follow-up
• Compression ultrasound, venogram, IPG, or D-dimer performed PRIOR to assessment