Pradaxa or Warfarin for Prevention of Recurrent VTE in Patients With Angiographically Confirmed Acute Massive Pulmonary Embolism undergoIng Endovascular Mechanical Fragmentation and Thrombolytic Therapy

Inclusion Criteria: * Men and women aged \> 18 years * Angiographically confirmed acute massive pulmonary embolism with involvement of Central pulmonary arteries. * endovascular mechanical thrombus fragmentation + thrombolytic therapy (using recombinant tissue activator of plasminogen), performed for treatment of the above-mentioned pulmonary embolism in less than 48 hours before randomization. The patient should be randomized no earlier than 24 hours after procedures endovascular mechanical thrombus fragmentation + thrombolytic therapy * Written informed consent signed by patient. Exclusion Criteria: * Signs of hemodynamic instability (i.e. systolic blood pressure \<100 mm Hg.St. or episode of systolic blood pressure fall for ≥40 mm Hg. / or heart rate \> 110 lasting more than 15 min) or need for ventilatory support within 12 hours prior to randomisation. * The indication for oral anticoagulation, associated with others disease. * malignant neoplasm of any location * Contraindications to warfarin or pradaxa according to Russian Instructions for medical use of these drugs * Indications for concomitant treatment with antiplatelet agents * Any stroke within 6 months before randomization * Intracranial hemorrhage in anamnesis * Active bleeding, bleeding diathesis. * Clinically significant bleeding within the last 30 days. * Trauma or extensive surgery within 1 month before randomization or surgery planned in the next 6 months after randomization. * Intracranial pathology: tumor, arteriovenous fistula or aneurysm. * Gastrointestinal bleeding in the previous 3 months. * Gastric ulcer or duodenal ulcer with clinical manifestations or endoscopically identified acute ulcer without signs of scarring during previous 30 days. * Uncontrolled hypertension (systolic blood pressure\> 180 mm Hg. and / or diastolic blood pressure\> 100 mm.hg in patients receiving antihypertensive drugs). * Pregnancy, lactation. * Life expectancy \<6 months. * Clinically significant liver disease. * Creatinine clearance (estimated by Cockcroft-Gault) \<30 ml / min. * hemoglobin level \<90 g/l), thrombocytopenia \<100x10\^9 / L. * Patients who, in the opinion of the researcher, are not suitable for inclusion in the study, for example, due to the low likelihood of doctor's recommendations following. * Long-term use of NSAIDs * Current participation in another clinical study. * Allergic to contrast substance or radioisotope drugs used in procedures to assess endpoints of the study, which according to researchers, may be a contraindication to the implementation of these research methods.