Post-Thrombotic Syndrome (PTS) Risk Factors Following First DVT Episode

 

Patient selection: first episode of unprovoked proximal deep vein thrombosis AND absence of primary venous insufficiency

 

Exclusion: moderate to severe venous ectasia in contralateral leg (evidence of primary venous insufficiency)

 

Outcome: post-thrombotic syndrome (PTS)

 

Key risk factors for PTS:

(1) obesity (body mass index >= 30 kg per square meter)

(2) mild venous unsufficiency (venous ectasia) in the contralateral leg

 

Additional factors that may contribute to the risk of PTS:

(1) poor INR control (based on percent of specimens with inadequate anti-coagulation, with INR <2)

(2) residual venous obstruction on baseline ultrasound (with wall thickening)

 

A patient with risk factors for the post-thrombotic syndrome should have preventive measures taken such as compressive stockings with confirmation of compliance. If poor INR control is an issue then this should be improved.