Elastic Compression Stockings for Prevention of Post-thrombotic Syndrome (CELEST)

• To show that elastic compression with ankle pressure targeted at 25 mm Hg is not inferior in preventing the onset of clinical post-thrombotic syndrome to a target ankle pressure of 35 mm Hg (recommended pressure being greater than 30 mm Hg) [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
  cumulative incidence 24 months after inclusion of PTS apparition defined by the villata score > or equal to 5. A visual guide will be given to investigators to assist them and standardize PTS evaluation. Investigators will receive a Villalta training during set up visits.
  
  

• superiority of targeted pressure at 35 mm Hg for compliant patients. Analysis of the primary endpoint per protocol amongst patients responding to the definition of compliance for compression scheduled by randomisation [ Time Frame: 24 months ] [ Designated as safety issue: No ]
  analysis of primary endpoint (cumulative incidence of PTS) amongst patients responding to the definition of observance for compression scheduled by randomisation. It means a per protocol analysis. The per protocol analysis defined as follow : patients ideally compliant (see next secondary outcome measure with self declaration of compression carrying superior or equal to 80 % especially)and patients with respect to randomisation.
  
  
• Superiority of 25 mm Hg on the therapeutic compliance criterion [ Time Frame: 24 months ] [ Designated as safety issue: No ]

  Superiority of 25 mm Hg on the therapeutic compliance criterion at 24 months

  Compliance is defined by 3 conditions :

  1. Morisky-Green score adjusted between 0 and 2

  2. because of French clinical pratices it should be pertinent to take into consideration 2 compliance type :

     1. ideal compliance : Self declaration ≥ 80 % (reference PRANDONI)
     2. adequate compliance : self declaration between 50 and 79% for (French references Delluc and Optimev study)
  3. return of used stockings ≥ to 80%
  
  
• superiority of 25 mm Hg for constraints related to compression and chronic venous insufficiency quality of life (CIVIQ) [ Time Frame: 3 months, 12 months, 24 months ] [ Designated as safety issue: No ]
  CIVIQ quality of life (CIVIQ 20) specific to chronic venous insufficiency at 3 months, 12 months and 24 months and questionnaire about constraints of compression stockings.
  
  
• non inferiority of 25 mm Hg for the comparative evaluation of the symptomatic effect of short-term compression (pain, sensation of oedema) form baseline to 3 months [ Time Frame: 3 months ] [ Designated as safety issue: No ]
  Comparison of evolution at short-term (3 months) of venous thrombosis symptoms (pain, oedema feeling). Self assessment by VAS of pain and oedema feeling once a week during 3 months. Assessment by the investigator at inclusion and during visit at 3 months (ankle measurement, clinical signs) will be done also. A statistical analysis will be done as soon as 3 months follow up data will be verified to evaluate symptoms evolution due to deep venous thrombosis.
  
  
• Non-inferiority of 25 mm Hg for changes in overall quality of life evaluated on the basis of the EUROQUOL questionnaire [ Time Frame: 3months, 12 months, 24 months ] [ Designated as safety issue: No ]
  Non-inferiority of 25 mm Hg for changes in overall quality of life evaluated on the basis of the EUROQUOL questionnaire (EQ5D)
  
  
• non inferiority of 25 mm Hg for the intensity of long term chronic venous insufficiency symptoms (12 months and 24 months) [ Time Frame: 12 and 24 months ] [ Designated as safety issue: No ]

  Long term assessment of evolution and intensity of symptoms (pain, oedema feeling) related to potential post-thrombotic syndrom apparition

  • Monthly self-assessment by VAS for pain and oedema feeling during 24 months. It will be done at the end of each month and will focus on symptoms intensity (last week of the month)
  • An assessment will be done by investigator, in addition of previous criterion, at 12 and 24 months
  • Assessment with the Ginsberg score (interview by the investigator at 12 and 24 months)
  • Comparison of averages on Villalta score (quantitative)
  
  
• non inferiority of 25 mm Hg for the onset of permanent trophic disorders [ Time Frame: 3 months, 12 and 24 months ] [ Designated as safety issue: Yes ]
  CEAP classification evaluated by investigator at 3, 12 and 24 months
  
  
• non inferiority of 25 mm Hg for the onset of sequelae or post thrombotic residues on an duplex scan at 3 months, 12 and 24 months [ Time Frame: 3, 12 and 24 months ] [ Designated as safety issue: Yes ]

  Assessment by duplex scan of deep and superficial veins at 3, 12 and 24 months

  • Assessment by duplex scan of deep reflux (>1s in femoral vein, and/or popliteal vein, tibio peroneal trunck)
  • Assessment by duplex scan of superficial reflux (> 0.5s in great saphenous vein, small saphenous vein, perforating veins)
  • Assessment by echographic score of thickness and location of residual thrombus
  • Assessment by duplex scan of re-canalization of collectors trunks and/or parietal sequalae
  
  
• testing for the prognostic factors of the onset post thrombotic syndrome and comparison of the onset kinetics of post thrombotic syndrome [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]

  variables tested as pronostic factors of post thrombotic syndrom apparition :

  • location of the upper pole of thrombus
  • kinetic of thrombus lysis by duplex scan at 3 months
  • Idiopathic nature of TED
  • Delay of diagnostic of deep venous thrombosis
  • Initial intensity of deep venous thrombosis symptoms
  • Initial evolution of symptoms of deep venous thrombosis between J0 and 3 months
  • Persistence of the symptoms at 3 months
  • Patient's characteristics
  • Kinetic of of Villalta score apparition ≥ 5 by survival curve
  • Kinetic of post thrombotic syndrom apparition by Villalta score
  
  
• test for key factors in good compliance [ Time Frame: 24 months ] [ Designated as safety issue: No ]
  Compliance evaluation according to the 3 axes defined on third outcome measure and research of determinants of good compliance by specific questionnaire
  
  
• Adverse events [ Time Frame: 24 months ] [ Designated as safety issue: Yes ]
  description and comparison of the incidence of adverse events including unexpected adverse events, events expected with this type of disease (recurrence of the venous thromboembolic disease, recurrence of deep vein thrombosis, pulmonary embolism, superficial venous thrombosis, venous ulcer) and events possibly related to the study treatment (arterial decompensation passing to Lerich stage III or IV, skin intolerance)
  
  
• Subgroups analysis of the primary objective and secondary objectives according to the gender stratification criterion and age [ Time Frame: 24 months ] [ Designated as safety issue: No ]
  Stratification on age (more or less than 65 years-old) for testing the hypothesis by subgroups analysis of the benefit of a better adaptation of compression 25 mm Hg on older subjects, as suggested by S. Khan.
  
  

CELEST trial is a controlled, randomized, multicentre, non-inferiority double-blind trial which aims to determine whether ECS applying 25mmHg of targeted pressure at the ankle are non inferior to ECS applying 35mmHg of targeted pressure at the ankle. Patients with a first acute symptomatic proximal DVT will be randomized to wear for two years either ECS applying 25mmHg of targeted pressure at the ankle or ECS applying 35mmHg of targeted pressure at the ankle. All patients will be prescribed anticoagulants for at least three months. The primary outcome will be the rate of PTS assessed with the Villalta scale in both arms of the study during the 2 years study period. Rate of compliance,severity of PTS and quality of life in both groups will constitute the main secondary outcomes.