Rediscussing Anticoagulation in Distal Deep Venous Thrombosis.

Background: Distal deep venous thrombosis (DVT) accounts for approximately half of all the cases of lower limb thrombosis. The impact and management of this condition is still controversial. This study aims to evaluate the incidence of pulmonary embolism (PE) in patients with distal DVT in comparison to proximal DVT and evaluate the correlation between DVT and PE extension.

Methods: 100 patients with acute lower limb DVT diagnosed with whole leg Doppler ultrasound from January 2006 to December 2014 were retrospectively analyzed. Active investigation for PE was carried out in all patients using multislice computed tomography angiography. Classification of DVT and PE was based on the proximal extension of the thrombus.

Results: The overall incidence of PE in our sample patients was 72%. In the subgroup analysis, incidence of PE was equal in both the proximal and distal DVT groups (77%, p > 0.99). PE was detected in 43% of the patients with isolated calf vein thrombosis (ICVT). No statistical difference was observed between the distribution of lobar, segmental and subsegmental PE in the 3 DVT subgroups (p = 0.665); however, truncular PE was only observed in the proximal DVT group.

Conclusion: Distal DVT is associated with a high incidence of PE compared to proximal DVT. Distal DVT and ICVT can provoke PE with involvement of proximal vessels in the pulmonary arterial tree, even in asymptomatic patients. Our study arises discussion in the controversial debate regarding the need for routine anticoagulation in distal DVT.