SILENT PULMONARY-EMBOLISM IN PATIENTS WITH DEEP VENOUS THROMBOSIS - INCIDENCE AND FATE IN A RANDOMIZED, CONTROLLED TRIAL OF ANTICOAGULATIONVERSUS NO ANTICOAGULATION

Objectives. A high frequency of asymptomatic pulmonary embolism (PE) i n patients with deep venous thrombosis (DVT) has been reported, but in formation about the outcome of the patients with PE remains sparse. Th e aims of the present study were to assess the prevalence of silent PE in patients with symptomatic, venographically proven DVT, and to eval uate the natural history of silent PE. Design. Consecutive patients fr om one centre of primary care were included in a randomized, open stud y with blinded control. All patients gave written, informed consent. S ubjects. Eighty-seven consecutive patients with venographically proven DVT and with a perfusion-ventilation lung scintigraphy performed with in 48 h of the DVT diagnosis were included. On the 10th and 60th days the lung scintigraphy was repeated in 80 and 60 patients, respectively . All the patients were followed for 3 months in the out-patient clini c. Interventions. All patients were ambulated from the first day and w ere allocated randomly to no anticoagulant (non-AC) therapy or to AC t herapy with intravenous heparin infusion for at least 6 days and oral AC therapy for 3 months. Results. Forty-three of these patients had a high probability lung scintigraphy for PE. Distal vein and femoral vei n thrombosis embolized in 33 and 53% of patients, respectively. The pr ogression rate after 60 days was 3% in both the AC and the non-AC grou p and after 10 days the rates were 13 and 8%, respectively. Conclusion s. A high frequency of silent PE in patients with DVT both above and b elow the knee is demonstrated. AC treatment did not influence the reso lution rate of PE or the rate of clinical PE in a 3-month follow-up pe riod.