Deep Vein Thrombosis
Conditions
Keywords
Deep vein thrombosis, Diagnostic management, Recurrent, MRI, Ipsilateral
Brief summary
The Theia-study is a prospective, multicenter, single-arm management (cohort) study. Consecutive patients with clinically suspected acute, recurrent, ipsilateral, proximal deep vein thrombosis (DVT) of the leg, who fulfil all the inclusion criteria and meet none of the exclusion criteria, are eligible for inclusion and will be managed according to the result of a magnetic resonance direct thrombus imaging (MRDTI) of the affected leg. The MRDTI is to be performed and adjudicated within 24 hours of study inclusion. The final treatment decision will be made based on this ruling of the MRDTI. In case of a positive MRDTI signal, patients will be treated with therapeutically dosed anticoagulants or modified in patients with a recurrent DVT on anticoagulant therapy. Patients with a negative MRDTI ruling will be left untreated, or treatment will be remained unadjusted if they are on anticoagulant treatment at inclusion. All patients with negative MRDTI will be subjected to a standardized compression ultrasonography (CUS) within 48 hours after initial presentation. The latter CUS serves as a reference test in case the patient returns with symptoms of ipsilateral recurrence in the future, and will not be used for management decisions at baseline. The study flowchart can be found in Appendix A. All patients will be followed for three months for the occurrence of acute recurrent venous thrombo-embolism (VTE). In case of suspected recurrent VTE, objective testing including either computed tomography pulmonary angiography (CTPA) for PE or CUS for DVT will be performed. Additionally, in case of a proven ipsilateral recurrent DVT during follow-up, MRDTI will be repeated.
Detailed description
See below.
Interventions
OTHERMRDTI
MRDTI is primary diagnostic test for management of suspected ipsilateral DVT
Sponsors
Trombosestichting Nederland
Leiden University Medical Center
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. Ability of subject to understand the character and individual consequences of this study; 2. Signed and dated informed consent of the subject available before the start of any specific study procedures; 3. Age ≥18 years; 4. Suspected acute recurrent ipsilateral DVT, as defined by a documented prior objectivated episode of DVT in the same leg as current symptoms originate from
Exclusion criteria
1. General contraindications for MRI: claustrophobia, pregnancy, intracranial vascular clips, any ferromagnetic implants, presence of a cardiac pacemaker or defibrillator, metallic splinters in the eye, any trauma or surgery which may have left ferromagnetic material in the body; 2. CUS-proven acute symptomatic DVT within 6 months before current presentation; 3. Onset of symptoms suggestive of acute recurrent DVT more than 10 days prior to presentation; 4. Suspected acute PE; 5. Hemodynamic instability at presentation (as a consequence of concurrent acute PE or otherwise); 6. Medical or psychological condition that would not permit completion of the study or signing of informed consent, including life expectancy less than 3 months, or unwillingness to sign informed consent; 7. Non-compliance or inability to adhere to treatment or follow-up visits. 8. Patients with suspected acute, recurrent, ipsilateral DVT on therapeutic anticoagulant treatment \> 48 hours at inclusion\* Note: \*From August 2015 onward, patients with suspected acute, recurrent, ipsilateral DVT on anticoagulant treatment were allowed in the study as they were found to represent a high proportion (30%) of the screened study population.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| 3-month incidence of recurrent VTE in patients with negative MRDTI | 3-month follow-up | Primary outcome is subdivided in two main outcomes: 3-month incidence of recurrent VTE in 1) patients with negative MRDTI for both DVT and thrombophlebitis who were not treated with any anticoagulant during follow-up and 2) all patients with negative MRDTI for DVT; these recurrences need to be objectively confirmed by either CT (for acute PE), or CUS with the baseline CUS serving as reference. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| 3-month incidence of recurrent VTE in patients with normal D-dimer test and unlikely clinical probability according to the Wells clinical decision rule for DVT | 3-month follow-up | the 3-month incidence of recurrent VTE in patients with low probability Wells score and a normal D-dimer test at baseline |
Other
| Measure | Time frame | Description |
|---|---|---|
| The feasibility of MRDTI in day to day clinical practice | First 24 hours after presentation to the emergency ward (post-hoc analysis) | The feasibility of MRDTI in day to day clinical practice: percentage of eligible patients that had to be excluded due to logistic reasons such as unavailability of MRDTI within 24 hours of presentation. |
| Inter-observer variability of MRDTI | After the study has been completed, all MRDTI studies will be re-evaluated (post-hoc analysis) | The inter-observer variability of MRDTI in daily clinical practice: all MRDTI scans will be review post-hoc by two independent experts to determine the alpha statistic between the readings in clinical practice and that by experts. |
| a formal cost-effectiveness and cost-utility analysis | This model will be based on the primary and secondary endpoints, scored after a follow-up period of 3 months (post-hoc analysis) | A Markov model will be developed to estimate the cost-effectiveness MRDTI versus ultrasonography. The model will follow the patients through the course of disease in a maximum of two three-month cycles, and will include all relevant clinical outcomes and incorporated health states stratified by diagnostic management. Clinical events included in the model are fatal PE, recurrent VTE, major bleeds and clinically relevant non-major. The model includes clinical and cost outcomes, along with incremental cost-effectiveness ratios (ICERs) and net monetary benefits (NMBs). |
Countries
Canada, Israel, Netherlands, Norway, Sweden
Outcome results
None listed