Diagnosis of deep vein thrombosis recurrence: Ultrasound criteria

Introduction: Recurrent deep vein thrombosis (DVT) is often suspected in patients after anticoagulant drug withdrawal. The clinical signs can be confused with the onset of post-thrombotic syndrome. For these reasons, diagnosis of DVT recurrence must rely on an accurate method. Materials and methods: In order to assess this challenging clinical issue, we performed an overview of the literature regarding ultrasound criteria for the diagnosis of recurrent DVT through a Medline search, which included articles published from January 1, 1980 to February 20, 2017. Results: Eighty-eight publications were found based on the defined keywords, of which nine articles with a relevant abstract were selected. By searching the reference lists of these nine articles, we obtained another 27 relevant articles. A new non-compressible vein or an increase in the diameter of a previously thrombosed vein segment by > 4 mm are sufficient to confirm the diagnosis of DVT recurrence. In contrast, an increase in diameter of < 2 mm enables recurrence to be ruled out. An increase between 2 and 4 mm is deemed equivocal. Criteria based on echogenicity and Doppler venous blood flow are not reproducible. Other diagnostic imaging methods, mainly direct thrombus magnetic resonance imaging, are currently under evaluation. Conclusions: Ultrasound remains the most useful test for the diagnosis of recurrent DVT. Further imaging tests need to be validated.