Baseline imaging after therapy for unprovoked venous thromboembolism: a randomized controlled comparison of baseline imaging for diagnosis of suspected recurrence

Abstract

Summary. Background: After a first unprovoked venous thromboembolism (VTE), many patients have residual pulmonary and/or lower limb vascular obstruction following completion of short‐term anticoagulation. Residual vascular obstruction may complicate the diagnosis of recurrent VTE. Whether baseline imaging, conducted after completion of anticoagulation, helps in interpreting diagnostic testing in patients who subsequently have suspected recurrent VTE is unknown. Study design: The REVERSE study is a cohort study whose primary aim was to derive a clinical decision rule to guide the duration of anticoagulation after a first unprovoked VTE. All patients underwent baseline imaging after completing 5–7 months of anticoagulant therapy. We performed a post hoc randomized controlled comparison among 121 patients investigated for a suspected recurrent VTE during follow‐up: the decision on recurrent VTE with or without baseline imaging was made available to two independent adjudicators. Results: The proportion of patients not classifiable for recurrent VTE was statistically significantly higher in the group with no baseline imaging than in the group with baseline imaging: one in five as compared with one in 25. The interobserver agreement between the two adjudicators was better in the group with baseline imaging than in the group with no baseline imaging: κ‐values were 0.78 and 0.54, respectively. Conclusions: In patients with a first unprovoked VTE, baseline imaging at completion of anticoagulant therapy helps in interpreting diagnostic tests performed in cases of suspected recurrent VTE.

Duplex imaging of residual venous obstruction to guide duration of therapy for lower extremity deep venous thrombosis

“…However, differentiating between RVO and recurrent ipsilateral DVT can occasionally be challenging, and duplex imaging after completion of anticoagulation has been shown to improve the accuracy for diagnosis of VTE recurrence. In a large cohort study by Hamadah et al, 15 patients with a first unprovoked DVT received 5 to 7 months of OAC. There were 121 patients in whom VTE recurrence was suspected.…”

“…Testing for this purpose usually is performed when antithrombotic therapy is being discontinued. 15 The third potential role for surveillance imaging is to detect the presence of RVO as a marker for patients at elevated risk for VTE recurrence.…”

Deep Vein Thrombosis

“…In particular, lack of early recanalization (after 3 months) appears to be more strongly associated with the risk of recurrence (Tan et al 2011). Independent of assessing residual thrombus as a predictor for recurrence, it is useful to document size and extent of the thrombus before discontinuation of OAC, as this will greatly help to diagnose or exclude a recurrent DVT, if the patient presents with new symptoms, after OAC has been stopped (Hamadah et al 2011). …”

Current standings in diagnostic management of acute venous thromboembolism: Still rough around the edges

“…Third, it has been suggested that residual thrombi after a first PE may complicate the interpretation of imaging tests in case of clinically suspected recurrent PE. Therefore, assessment of the presence of residual thrombi after completion of anticoagulant treatment was proposed to facilitate differentiation between residual and new thrombi in case of a clinically suspected recurrent PE 47 . While older studies reported a high prevalence of residual PE, 57% at 6 months after diagnosis of PE in a systematic review, recent studies have reported a high complete PE resolution rate of 84-…”