Prospective Studies on Diagnosis, Prevention, and Management of Deep Vein Thrombosis (DVT), DVT Recurrence and the Post-Thrombotic Syndrome (PTS): From Concept to Study Design in the Primary Care Setting
Abstrakt
The requirement for a safe diagnostic strategy of deep vein thrombosis (DVT) should be based on an overall objective post incidence of venous thromboembolism (VTE) of less than 1% during 3 months follow-up. Compressionultrasonography (CUS) of the leg veins has a negative predictive value (NPV) of 97% to 98% indicating the need of repeated CUS testing within one week.
A sensitive ELISA VIDAS safely excludes DVT and VTE with a NPV between 99 and 100% when the clinical score is low to zero. The combination of low clinical score and a less sensitive D-dimer test (Simply Red or Simplify) is not sensitive enough to exclude DVT and VTE in routine daily practice.
From prospective clinical research studies it may be concluded that complete recanalization within 3 months and no reflux is associated with a low or no risk of PTS obviating the need of MECS 6 months after DVT. Partial and complete recanalizationafter 3 to more than 12 months is usually complicated by reflux due to valve destruction and symptomatic PTS.
Reflux seems to be a main determinant for not only for PTS and but also for DVT recurrence, the latter as a main contributing factor in worsening PTS. This hypothesis is supported by the relation between the persistent residual vein thrombosis(RVT=partial recanalization) and the risk of VTE recurrence in prospective studies.
Absence of RVT at 3 monthspost-DVT and no reflux is predicted to be associated with no recurrence of DVT (1.2%) during follow-up obviating the need of wearing medical elastic stockings and anticoagulation at 6 months post-DVT. The presence of RVT at 3 months post-DVT with reflux after 6 months post-DVT is associated with both symptomatic PTS and an increased risk of VTE recurrence in about one third in the post-DVT period after regular discontinuation of anticoagulant treatment.