«Authors: Alice Marinho (amomarinho Carlos Veterano (carlos_veterano Maricruz Nunes (maricruznunes Patrícia ...»
Another adjunctive procedure often used is pneumatic compression bands. This helps maintaining intermittent blood flow through the vein, in order to prevent development and propagation of thrombus residues during treatment.
All of these techniques are used to optimize the results of both catheter and anticoagulation therapy alone by decreasing the risks associated with it.  Lysis and patency There is a scale that quantifies clot lysis in percentages. Lysis grades II and III represent satisfactory results, because they represent more than 50% of lysis. (Table 1) Lysis success also depends on the place affected and the thrombus age. The older the thrombus the more difficult it gets to achieve total lysis. 
In this forest plot, it can be observed that odds ratio is higher than 1, which means that lysis is higher on CDT treatment. The size of the squares represents the weight of each article based on Jadad‟s scale. The overall clearly points to a greater lysis with the catheter.
In short-term follow up, patients treated with CDT obtain better patency than those treated with anticoagulation therapy, which is easy to understand once that rate of lysis is higher in CDT group.
Venous obstruction This forest plot follows the same logic as the previous one, but instead of lysis, we measure venous obstruction six months after the treatment. Odds ratio is smaller than one, which means that venous obstruction is higher on anticoagulation therapy. It can also be noticed that the second trial has a horizontal line (that corresponds to error) that crosses the vertical odds ratio=1 line, meaning that this article has no statistical meaning.
Thrombocytopenia Regarding conventional anticoagulation therapy, heparin induced thrombocytopenia has been reported. Type I thrombocytopenia, is caused by hypersensitivity to the drug which results in a dangerous decrease of blood platelets levels; type II, which appears in 1% of the patients, is caused by an immune reaction on which the body produces antibodies against the complex heparin-platelet factor 4 (PF4). The formation of the complex antibody-heparine+PF4 leads to destruction of blood platelets which is potentially fatal and causes thrombo-embolic complications in about 20% to 30% patients. 
One of the risks associated with CDT is the occurrence of bleeding since it is an invasive technique. According to Gogalniceanu et all (2009) 5-11% of the patients suffered bleedings related to CDT. Most of the incidents recorded were associated with puncture site bleeding. Data from the USA National Venous Registry shows that DVT can cause intracranial haemorrhage. However, this complication is uncommon. Bleeding complications normally occur in CDT because the initial puncture did not secure venous access.  In a study of 2005, it is reported that bleeding occurs in 4 of 45, mainly confined to the puncture site. 
Complications evolving pulmonary embolism (PE) after CDT-treatment have been reported in 4,5% of the cases. However when CDT and LMWH (low-molecular-weight heparin) are combined in  the treatment of DVT, the incidence of symptomatic PE is less than 2%.
This complication may occur also when patients are treated with anticoagulation therapy alone. This was shown in a study on which 6% of patients had pulmonary embolism, while anyone of patients treated with CDT had.  Death Death is rare, but possible due to complications with catheter-directed thrombolysis. There is few data concerning mortality related to CDT when compared to anticoagulation alone, although  rates of 0-0,4% have been suggested. However, in a study made by Baekgaard N. et Al., and published in 2009, the rate of mortality was 0%. There is limited information about mortality rates, in both treatments, so it can‟t be used to quantify the efficacy of each.  A study that compares the two treatments, revels that during the first year after the treatment, mortality rate was 0%. However, after 5 years, mortality rate in anticoagulation therapy patients was 14%, and in CDT group the rate was 19%.  Others authors reported that in their study, in which patients with DVT were treated with CDT, mortality rate was 1%. Deaths occurred after the patients were treated, due to pulmonary embolism and intracranial haemorrhage.  Post-thrombotic symptoms According to a scientific paper of 2009, post-thrombotic symptoms appear 2-3 years after the thrombotic event.  The causes of PTS are: chronic venous hypertension secondary to venous reflux, venous obstruction and valve‟s dysfunction. It is estimated that 80% of patients treated with CDT may develop post-thrombotic symptoms.  The application of a stent may cause pain, bleeding from the insert site and damage to the blood vessel, due to its invasive character.  Discussion The conventional treatment is anticoagulation therapy associated with compression bands or stockings. The anticoagulation prevents an increase in the extension of the thrombus, the recurrence of DVT, the pulmonary embolism and death. However, since this therapy rarely reaches total lysis, the rate of venous obstruction is higher, just like the rate of venous reflux, which is higher too. The compression therapy aims to reduce the risk of developing long-term sequels, which is postthrombotic syndrome.
CDT (Catheter-directed Thrombolysis) allows rapid and effective thrombus removal with less thrombolytic systemic effect, reducing the risk of developing post-thrombolytic syndrome. In this treatment, there is a larger rate of lysis, so the patency of the vessel will also be larger, saving the venous valves. Combining the effective removal of the thrombus achieved by this treatment with the anticoagulant therapy causes a significant reduction in the recurrence rate.
ConclusionBased on the information we gathered and the meta-analysis that was made, it is legitimate to conclude that anticoagulation therapy alone or the conventional treatment (anticoagulation therapy associated with compression bands or stockings) are not enough. The best treatment for DVT (deep vein thrombosis) is CDT (Catheter-directed thrombolysis) followed by anticoagulation therapy, because it ensures greater lysis in short-term and prevents recurrence.
References (1) Gogalniceanu P, Johnston CJ, Khalid U, Holt PJ, Hincliffe R, Loftus IM, Thompson MM.
Indications for thrombolysis in deep venous thrombosis. European Journal of Vascular Endovascular Surgery 2009; 38:192-198 (2) Jackson M., M. D., Wang X. et al. Catheter-directed thrombolysis and/or thrombectomy with selective endovascular stenting as alternatives to systemic anticoagulation for treatment of acute deep vein thrombosis. The American Journal of Surgery 2005; 190: 871-876 (3) Janssen MC, Wollersheim H, Schultze-Kool LJ, Thien T. Local and systemic thrombolytic
therapy for acute deep venous thrombosis. The Journal of Medicine (Netherlands). 2005; 63:
81-90 (4) Broholm R, Panduro Jensen L, Baekgaard N. Catheter-directed thrombolysis in the treatment of iliofemoral venous thrombosis. International Journal of Angiology 2010; 29: 292-302 (5) Wicky S. Acute Deep Vein Thrombosis and Thrombolysis. Tech Vasc Interventional Rad 2009;
12: 148-153 (6) Justo L., Soares B., Calil H. Revisão sistemática, metanálise e medicina baseada em evidências: considerações conceptuais. Jornal brasileiro de Psiquiatria 2005; 54: 242-247 (7) Meissner M. Conventional Anticoagulant Therapy Remains the Current Standart of Care for the treatment of iliofemoral Deep Venous Thrombosis. Dis mon 2010; 56: 642-652 (8) Rahman A., Cengiz Colak M. et al. A comparison of different treatment managements in patients with acute deep vein thrombosis by the effects on enhancing venous outfl ow in the lower limb. Medical Science Monitor 2009; 15: CR588-593 (9) Bækgaard N., Broholm R. et al. Long-Term Results using Catheter-directed Thrombolysis in 103 Lower Limbs with Acute Iliofemoral Venous Thrombosis. European Journal of Vascular and Endovascular Surgery 2009; 39: 112-117 (10) AbuRahma A., Perkins S. et al. Iliofemoral Deep Vein Thrombosis: Conventional Therapy versus Lysis and Percutaneous Transluminal Angioplasty and Stenting. Annals of Surgery 2000; 233: 752-760 (11) Grewal N., Martinez J. et al. Quantity of clot lysed after catheter-directed thrombolysis for iliofemoral deep venous thrombosis correlates with postthrombotic morbidity. Journal of Vascular Surgery 2010; 51: 1209-1213 (12) Lin P., Zhou W. et al. Catheter-directed thrombolysis versus pharmacomechanical thrombectomy for treatment of symptomatic lower extremity deep venous thrombosis. The American Journal of Surgery 2006; 192: 782-788 (13) Enden T., KLØW E. et al. Catheter-directed thrombolysis vs. anticoagulant therapy alone in deep vein thrombosis: results of an open randomized,controlled trial reporting on short-term patency. Journal of Thrombosis and Haemostasis 2009; 7: 1268-1275 (14) Sillesen H., Just S. et al. Catheter Directed Thrombolysis for Treatment of iliofemoral Deep Venous Thrombosis is Durable, preserves venous Valve Function and May Prevent Chronic Venous Insufficiency. European Journal of Vascular and Endovascular Surgery 2005; 30: 556Elsharawyy M., Elzayat E. Early Results of Thrombolysis vs Anticoagulation in Iliofemoral Venous Thrombosis. A Randomised Clinical Trial. European Journal of Vascular and Endovascular Surgery 2002; 24: 209-214 (16) Park Y., Choi J. et al. Restoration of Patency in Iliofemoral Deep Vein Thrombosis with Catheter-Directed Thrombolysis Does Not Always Prevent Post-Thrombotic Damage.
European Journal of Vascular and Endovascular Surgery 2008; 36: 725-730 (17) Benítez M., Gómez I. e al. Trombopenia inmune inducida por heparina en hemodiálisis a
propósito de un caso. Revisión de la literatura. Nefrologia 2007; 27:
(18) Mewissen M. et al. Catheter-Directed Thrombolysis for Lower Extremity Deep Vein Thrombosis. Techniques in Vascular and Interventional Radiology 2001; 4: 111-114