title: Relation between D-dimer level, venous valvular reflux and the development of post-thrombotic syndrome after deep vein thrombosis.
abstract: BACKGROUND
  The pathophysiology of post-thrombotic syndrome (PTS) is postulated to involve persistent venous obstruction and venous valvular reflux.
  
  
  OBJECTIVE
  To study the association between D-dimer level, valvular reflux and the PTS in a well-defined cohort of deep vein thrombosis (DVT) patients.
  
  
  METHODS
  Consecutive patients with acute symptomatic DVT were recruited at eight centers and were followed for 24months. D-dimer was measured at 4months. A standardized ultrasound assessment for popliteal valvular reflux was performed at 12months. Using the Villalta scale, patients were assessed for PTS during follow-up by evaluators who were unaware of D-dimer or reflux results.
  
  
  RESULTS
  Three hundred and eighty-seven patients were recruited; of these, 305 provided blood samples for D-dimer and 233 had a 12-month reflux assessment. PTS developed in 45.1% of subjects. Mean D-dimer was significantly higher in patients with vs. without PTS (712.0 vs. 444.0μgL(-1) ; P=0.02). In logistic regression analyses adjusted for warfarin use at the time of D-dimer determination and risk factors for PTS, D-dimer level significantly predicted PTS (P=0.03); when stratifying for warfarin use at the time of blood draw, adjusted odds ratio (OR) for developing PTS per unit difference in log D-dimer was 2.33 (95% CI 0.89, 6.10) in those not on warfarin vs. 1.25 (95% CI 0.87, 1.79) in those on warfarin. Ipsilateral reflux was more frequent in patients with moderate-to-severe PTS than in patients with mild PTS (65% vs. 40%, respectively; P=0.01) and was independently associated with moderate-to-severe PTS in logistic regression analyses (P=0.01).
  
  
  CONCLUSIONS
  D-dimer levels, measured 4months after DVT in patients not on warfarin, are associated with subsequent development of PTS. Venous valvular reflux is associated with moderate-to-severe PTS.
authors.affiliation: Department of Medicine, McGill University, Montreal, Canada.
authors.forename: J
authors.initials: J
authors.lastname: Latella
authors.forename: S
authors.initials: S
authors.lastname: Desmarais
authors.forename: M-J
authors.initials: MJ
authors.lastname: Miron
authors.forename: A
authors.initials: A
authors.lastname: Roussin
authors.forename: F
authors.initials: F
authors.lastname: Joyal
authors.forename: J
authors.initials: J
authors.lastname: Kassis
authors.forename: S
authors.initials: S
authors.lastname: Solymoss
authors.forename: L
authors.initials: L
authors.lastname: Desjardins
authors.forename: J S
authors.initials: JS
authors.lastname: Ginsberg
authors.forename: S R
authors.initials: SR
authors.lastname: Kahn
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D005338:Fibrin Fibrinogen Degradation Products / Q000096:biosynthesis*; D006801:Humans; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D054070:Postthrombotic Syndrome / Q000097:blood* / Q000150:complications; D011446:Prospective Studies; D012307:Risk Factors; D014689:Venous Insufficiency / Q000097:blood* / Q000150:complications*; D020246:Venous Thrombosis / Q000097:blood* / Q000150:complications
chemical_list: D005338:Fibrin Fibrinogen Degradation Products; C036309:fibrin fragment D