Endovascular Management of Deep Venous Thrombotic Diseases of the Lower Extremity

Pulmonary embolism and venous ischemia are acute complications of deep vein thrombosis (DVT) of the lower extremities. Delayed complications include a spectrum of debilitating symptoms referred to as postthrombotic syndrome (PST). Because the early symptoms and patient signs are nonspecific for DVT, careful history taking and radiological evaluation of the extent and migration of thrombus should be used to establish an objective diagnosis and the need for treatment. Anticoagulation therapy is recognized as the mainstay treatment in acute DVT. However, there are few data to suggest any major beneficial effect of the early clearing of massive DVT and PTS. Endovascular, catheter-directed, thrombolysis techniques, used alone or in combination with mechanical thrombectomy devices, have been proven to be highly effective in clearing acute DVT, which may allow the preservation of venous valve function and the prevention of subsequent venous occlusive disease. Definitive management of the underlying anatomic occlusive abnormalities should also be undertaken.

Deep Venous Thrombosis in the Lower Extremity: Catheter-Directed Thrombolysis

PURPOSE: To evaluate the efficacy of catheter-directed thrombolysis in treating symptomatic deep venous thrombosis (DVT) in lower limbs. MATERIALS AND METHODS: Twenty-six consecutive patients (16 male and 10 female; mean age, 55 years) with lower extremity DVT underwent thrombolytic therapy. The duration of symptoms was 1 -90 (mean, 17) days: 20 days or less in 16 cases (acute DVT) and less than 20 days in ten (chronic DVT). Catheter-directed infusions of urokinase were administered via ipsilateral popliteal veins, and angioplasty or stent placement was performed after the thrombolytic procedure. Oral medication of warfarin continued for six months, and for the evaluation of venous patency, follow-up ultrasonography was performed. The total dose of infused urokinase was 1,750,000 -10,000,000 (mean 4, 84,000) IU, and the total procedural time was 25 -115 (mean, 64) hours. RESULTS: Lysis was complete in 16 cases (62%, all acute DVT), partial in five (19%, chronic DVT), and failed in five (19%, chronic DVT). Eight patients with venous stenosis and two with occlusion were treated by means of angioplasty (n=4) or Wallstent placement (n=6). Minor bleeding occurred in six cases and major complications in two (one of pulmonary embolism, and one of multiorgan failure). CONCLUSION: Catheter-directed thrombolysis with urokinase is effective for the treatment of DVT in lower limbs.

Study on Effectiveness and Safety of Portal Vein Embolization using a New Liquid Embolic Material(Embol-78-12)in Pigs

PURPOSE: To evaluate the effectiveness and safety of a new liquid embolic material, Embol-78-12, in portalvein embolization (PVE) in pigs. MATERIALS AND METHODS: A total of 13 pigs were used in this study. The testmaterial, Embol-78-12, was obtained by hydrolysis of polyvinyl acetate (PVAc) and dissolved in a mixture of 45%ethanol and 55% nonionic water-soluble contrast medium (Ultravist 370) (v/v). Its radioopacity was good. PVEinvolved the use of 5cc of Embol-78-12 in the left lobe (left and left paramedian segments) of the liver ; toprevent reflux of the embolic material through the percutaneous transhepatic route, an oclusion balloon catheterwas used. Six pigs were sacrified immediately after PVE and formed a normal control group, used to determine theaverage volume ratio of the right and left lobe of the pig. Follow up study was performed in the other seven pigs; changes in body temperature and liver function test (GOT, GPT, and total bilirubin) at 0, 3, 6, 10, 14 daysafter PVE were recorded. Four pigs were sacrificed at 2 weeks, and three at 4 weeks. The embolization rate,changes in the volume ratio of the right and left lobe, the atrophy ratio of the embolized lobe and regenerationrate of the non-embolized lobe were evaluated. RESULTS: In the left lobe, PVE was successfully completed in allpigs. Follow-up study revealed evidence of increased body temperature in only one of six pigs and virtually nochange in GOT, GPT, and bilirubin levels. In the control group, average liver volume was 511+43 cm3 ; volumepercentage of the right and left lobe of the liver was 55+2% and 45+1, respectively. The embolization rate in thisstudy was 45+1%. When the animals were sacrificed at 2 and 4 weeks, embolized left portal vein showed completeocclusion. Volume percentage of the right and left lobe of the liver was 71+3 and 29+3 at 2 weeks, and 84+3 and16+3% at 4 weeks. The atrophy ratio of the embolized lobe was 22% at 2 weeks (average decrease : 51cm3) and 49% at4 weeks (average decrease : 114 cm3). The regeneration rate of non-embolized lobe was 12.6 cm3/day (176 cm3 for 2weeks) during the first 2 weeks and 8.9 cm3/day (125 cm3 for 2 weeks) during the next 2 weeks. CONCLUSION: Innormal pig liver, embol-78-12 used with occlusion balloon catheter is an effective and safe material for PVE. Webelive it is suitable for PVE in the clinical field and will be used in many clinical applications in the field ofinterventional radiology.